Inhibition of Nitric Oxide Synthase Activity and Nitric Oxide-Dependent ...

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Stamler. JS: Redox signaling: Nitrosylation and related target interactions of nitric oxide. Cell. 78: 931-936, .... PA, Nelson. Ri, Singer JW, Bursten. S: Protec-.
Inhibition Dependent Adenosine

of Nitric Oxide Calcium Influx Monophosphate: KENICHIRO Third Medicine

Abstract.

Cell

destruction

calcium

mechanisms

that

are

not

fully

II,

through

(Ca1)

defined,

but

proteins

from

thrombin

and

adenylyl

cyclase

understand signaling

effects

may

of adenylyl of adenylyl

Hypoxic

and

occurs

in

renal

production

(1-4).

severity to cell

epithelial

the

through

a variety

Ga1,

cooperate

to

injury

and

cell

to define

the

Ca influx

injury

frequently

activation

two

to these

and

events

intracellular

have

subsequent High

insults,

been

the

epithelial

calcium implicated

of experimental sysentry of extracellular

activation of proteases levels of NO may injure

of mechanisms,

including

eration and nitrosylation of proteins increased Ca levels or NO production

the

free

and cells

radical

gen-

(5-7). Evidence that the contribute to cell injury

Received

August

versity

of

Florida,

FL 32610. Dr. Jared Grantham disposition

20, 1996. Accepted to

of

this

Dr. Box

R.

Tyler

100224

served

December

Miller,

Internal

JHMHC.

1600

as Guest

Editor

MedicinefNephrology,

SW Archer

and supervised

manuscript.

Road,

Uni-

Gainesville,

the review

and

final

Copyright

of the American Society of Nephrology (C) 1997 by the American Society of Nephrology

influx

was

is modulated to

the

production.

phospholipase

was

authors

but by an

insensitive

conclude

and

that

by

indicated

Ca influx,

The

extent

by

by activa-

NO

that

by NO-dependent

that

blocked inhibited

regulates

mechanism cyclase.

on

which

inhibiting

that

bradykinin-stimulated

adenylyl

and

by

depends

and

kinase,

bra-

to

that

independent

increased

NO

Soc

Nephrol

8: 558-568,

by

preventing

the

macologically

the

mech-

Ca

of Ca across

is referred

including

NO

Ca

hormones

NO

cell

influx,

whereas

influx

pathway

the

cell

cGMP

the

(12,14).

in part

by

of

Ca-calmodulin,

eNOS, and

cy-

Ca entry In

reduce

reconstitute may

signaling NO

activ-

guanylyl

cyclase

in the

by three NOS,

(NOS)

(11,12,14-16).

in Ca1 or NO

of normal

to release

stimulates

space

In

factors,

to peptide

synthase

which

and

CRAC.

other

stimulates

or guanylyl

is controlled

or

in Ca1 due

Consequently,

or derangement

Ca influx

influx,

of NO or cGMP

increases

forms

of Ca

Release

in response

extracellular

readdition injury,

level,

from

(10).

A rise NO

Ca

event,

by

in turn

of NOS

of

modulated

production

stimulates

inhibitors

production

Ca

(1 1-14).

the

from

constitutive

regulated

by

in Ca1 phar-

1P3-mediated

to stimulate

be

production

raises

systems,

NO

be reduced

release

membrane

may

(!P3

or autocoids) This

the

release-activated influx

stores

Increased

activation

can

or rise

and

is required

production

of intracellular

ischemic

injury

by

the cell

stores

to as Ca cells,

the

cell

production

a phospholipase-C

intracellular

clase.

that

in NO

is regulated

stores,

epithelial

ity.

finding

(1,2,8,9).

influx

from

injury (J Am

1997)

increase

Intracellular and

Ca

production

contributes to increased Ca influx and cell injury, cell may be reduced by agents that activate adenylyl cyclase.

1046-6673/0804-0558$03.00/0 Journal

by

influx

these

30, 1996.

Ca

was

cyclase

production

by

increased that

influx

protein

cGMP-independent

into

Correspondence

NO

the 0 protein

C, also increased

intracellular

(Ca1) in

blocks

of Gaq.

is supported

of

Ca guanylyl

of cAMP-dependent

anisms,

injury,

of

initiated

Ga,3

by a mechanism

and

cyclase.

signals

thrombin.

increased

synthase

adenylyl

cAMP

inhibition

To

The Departments

of the

and

The

of NO

Expression

of the

injury.

cell

that

NO,

activators

and

components Ca influx

cGMP.

of

mech-

protein-dependent

or

In response

cell with derangements.

for

distinct of cell

0

pathogenesis of cell injury in a number tems. Ca-mediated cell injury involves Ca into metabolic

proteins

inflammation

increases

These

activators

this type of injury the levels of autoas thromboxane, thrombin, Ang II, and

are elevated.

NO

rises

tion

on bradykinin-stimulated

of

During such

distinct through

through

which

and

inhibitors

have

of the

of different for thromboxane

dykinin-stimulated

II act

receptors

in ameliorating

cyclase

clotting cascade. coids and peptides

the

contribute

setting

that

act

Japan;

Florida.

separation

NO

receptors

settings,

by

cyclase

ischemic

the

bradykinin

reduce

mechanisms

systems

role

cell

of experimental

of 0

MILLER

Kumainoto,

and NO in cultured renal epithelial cells that stably overexpress Gaq and Ga,3 were studied. This system allowed for the receptors

injury

as bradykinin,

members

0

in

The

cell

activation

such

cells

a rise

production.

families

These

of tissue

during

These

act through

system

the

setting

bradykinin and Ang Gaq families, whereas

in epithelial

In a number

Gainesville,

involve

substances

families.

NO

may

different

for and

of Florida,

with

NO

thrombin.

thromboxane

Gaq and Ga , regulate Ca1 and

the

for and

Receptors of the Ga1

University

NO

and

R. TYLER

University,

in the

increased

and

Kumamoto

is associated

in Ca

they

receptors

functions. members

anisms.

and

rises

thromboxane, 0

occurs and

trigger

protein-coupled Ang

frequently

TOMITA,

Medicine,

Pharmacology,

inflammation

intracellular

KIMIO

of Internal

and

injury

and

KITAMURA,

Department

Synthase Activity and Nitric Oxidein Renal Epithelial Cells by Cyclic Implications for Cell Injury

early

Ca

the Ca stages

occur

of

through

pathways. synthetic

and

bNOS

the

inducible

enzymes, that

are form,

Inhibition

iNOS its

The

(5,17,18). level

of

lipopolysaccharide cifically that

ofiNOS usually

(LPS).

induces

G

activity

expression,

iNOS

in renal

iNOS

ceptors

that

These

activate

levels. Substances act through

epithelial

will

cells,

mean

Ga13

are

spe-

GaqQ29L

of

for

re-

expression

and

to

activate

cyclase.

These

terized

signaling

phospholipase

receptors

have

ubiquitously

cell

through

line,

iNOS

thromboxane naling The

identified

(20,2

and

1

that

Ga,3

thrombin

and and

Gaq

,

and

agents

tissue

injury

steps

in these

found

models,

that

inhibited

are which

showed

processes

reduces

study

renal

In

NO

MgCl,,

in a

and

for

their

of

the

effects

of

cells

that

of Gaq

and

cell or

influx

titative

was

that

and

re-

(Boston,

(Eugene,

purchased supplies

OR).

MA). Tissue

Fura-2

cyclase

Ca

influx

medium,

serum,

from Molecular were

from GIBCO (Grand Island, NY). Tissue culture plastic were from Falcon (Oxnard, CA). Other chemicals were from

Sigma (St. (Pittsburgh,

Louis, PA).

MO)

or

(molecular

biology

grade)

from

Fisher

MCT

cells,

a gift

DMEM/Ham’s formed

when

an SV4O-transformed Eric

F-12 cells

studies.

in lysis

leupeptin. and

125

lysed

was

of Ca

buffer

(20

2 mM

mol

PMSF,

in a glass

dounce

at 1 200 X g to

centrifuged

Influx

fluorometrically

by measuring Mn

100%

in Fura-2-loaded

containing

rate

portion

increase

over

was

of the

quench

control

To

calculate

by Mn and

digitonin the tangent

or Neo cells.

was

One

cell

the cells

by measuring and

quan-

different

by exposing

and 75 pg/ml curve

the

to allow

and

determined

MnCl,

of intracellular

(12.14).

treatments

was

determined

Mn

untreated

nm

different

0.5 mM

of Ca influx

360

fluorescence

value

(SLM 8000at 510 nm. Ca

the rate of quench

at

among quench

( I 2,14). to the

presented

tracing

as fold

is considered

“n.”

whole

Activity crude

and

as conversion

NOS

activity

Bredt

and time

with

of NOS cells was

measured

Snyder

(35).

j.d of PBS

7.8

mM

glucose,

for

15 mm.

homogenates,

MCT

(pH

and

were

grown

the medium 7.3)

1 pCi

At time

cells

containing [3H]arginine

0, bradykinin

was 4.2

activity

was

Whole

cell

(l0

of the

technique

of

in 24-well

clusters.

At

removed mM

and

M and 2 x I0 M), or L-NAME the incubation was continued for

(10 and

NOS

to [3H]citrulline.

by a modification

of the experiments,

400

cell

of [3H]arginine

was

M), (5

an

and

KCI,

replaced

1 mM

incubated

forskolin

l0 additional X

CaC1,, at 37#{176}C

and

IBMX

M) were added 10 mm. The

reactions were stopped by adding 10 ,.d of 5-M TCA, and were held on ice for 30 mm. The supernatant was gently

(Dowex AG8 200-400); mM HEPES (pH 5.5).

from

neomy-

for

the plates removed,

extracted twice with 2 volumes of ether, and neutralized with 1.5 ml of 25 mM HEPES. Each reaction was then added to a 2-ml column

Cell Culture were

and

in

from En-

and G-4l8

on ice

smol

measured

of Fura-2

Measurement

were obtained from DuPont-New

was

quench

to medium

one

Ga13.

was purchased

culture

used

2 mM mercaptoethanol,

homogenate

extracellular

the

initial

led to

Ca

comparisons

types, The

findings, cyclase

adenylyl

scraped

inhibitor)

Measurement

by

have

induction,

and 25

trypsin

was quantitated

Fura-2

the

Nuclear

Probes

suffi-

expression

GaqQ2(,[ were

cells in suspension in a dual excitation microfluorometer C). Excitation was at 360 and 380 nm, and emission

we

Materials

gland

Ga,3

aprotinin,

soy

Intracellular

and Methods DNA modifying enzymes WI) and radionucleotides

a chain

was

Extracts

at 4#{176}C. The

measured

Restriction and Promega (Madison,

metal-

in G protein expressing

in PBS

TIU/ml

In both

Materials

pZem-

activity

pH 8, 150 mM NaCI,

Fluorescent

cells

the

cells

nuclei.

studies,

production,

express

remove

in MCT a mechanism

activation cGMP

0.2

percentage

and iNOS

using

by a mouse

of promoter

line

and

sig-

of cell

affect

washed

10 j.tg/ml

common

past

influx

through

cell injury

production,

epithelial

range

they

in MCT

expressing

Ga,

MCT cells expressing the mammalian exwithout an insert were used as controls

of Cell were

homogenizer

produc-

protein kinase (3 1). These that activation of the adenylyl

epithelial

on NO

Ca

of Ga

system

that

(24-30).

by activation cAMP-dependent with the fact

system

suggests

of

Ga13 was cloned was a gift of Silvio

(14,19,33).

mM NaHEPES

that

receptors Ga13,

in a wide

hormone-dependent

quired coupled the

effective

cell

cells

559

Expression

is driven

increases

neomycin-resistant vector pZem-228 cells)

expressed level

Influx

expression

(14,19,33). GaqQ2(L

expression

basal

A clonal

pooled

Cells

may contribute to cell injury (20). of cell injury can be reduced by administration

These

(33).

Preparation

are

mechanisms

Because

activate

regusecond

which

increases

(14,19).

The

measurable

activity

(Neo

of agents such as PGE2, PGE2 agonists, melanocyte-stimulating hormone, and phosphodiesterase inhibitors that raise cAMP.

to cause

Pooled pression

adenylyl

cell

promoter.

Cell and

previously PCR, and were

mammalian

lothionein

Mammalian

Ca

and throm-

we

by different

cDNAs

The

NO-Dependent

vectors,

(34).

cm-resistant

well-charac-

Gaq

).

Recently,

influx

induction

and

pathways severity

Ca

inhibit less

a chains, Gaq. whose effector

(22,23).

increase

and other

for thrombin

two 0 protein CJ3, and Ga,3, not been

epithelial

tion

C

activate

Receptors

expressed

and Gaq

renal

also

pathways.

boxane A2 activate lates phospholipase messenger

thromboxane, and thrombin domain, 0 protein-coupled

and described RNA by

where

and

such as bradykinin, seven transmembrane

receptors

Ga,3

228,

and

constructs,

were MCT cell

Gutkind

cient

NO

Activity

Constructs cDNA

from

capable

ligands

iNOS

cDNA The

demonstrating

that

increase

by

bacterial

that

systems

results

Ga13

and

showed

signaling

( 19).

primarily

cytokines

We recently

protein-dependent

inducing

is regulated by

of NOS

Neilson (50:50)

were

mouse (32).

plus

approximately

5%

proximal

Cultures FBS. 90%

tubule

were

cell line,

maintained

in

Experiments

were

per-

confluent.

Serum

was

removed 18 to 24 hours before experiments to minimize growth factors. Cell lines were maintained in G-4l8, removed 48 h or two passages before experiments.

effects of but it was

in a scintillation

protein the

mean

flavin

with

counter.

The counts

and are expressed

as CPM/mg

of triplicate

For measurement (100

eluted

2 mM EDTA,

j.d) contained adenine

in each prot/min.

well

were Each

wells ± SEM. of NO activity in cell homogenates, 50 p.g ofcell

dinucleotide

M), tetrahydrobiopterin

2 ml of solution

(10 (2 X l06

containing

and 2 mM EGTA;

homogenate,

20 mM

20

and counted normalized

point

for

represents

each reaction HEPES

M), flavin mononucleotide M), /3-reduced nicotinamide

pH 7.4, (l0 ade-

560

Journal

nine

of the American

dinucleotide

phosphate

Society

of Nephrology

(2 X l0

M),

EDTA

(5

I0

X

M),

CaCl, (5 X l0 M), arginine (2 X l0 M), [3Hlarginine (approximately 180,000 cpm); and l0 M cAMP (8-Br-cAMP) and protein kinase A (10 U of catalytic subunit in 3 mM DTT). where indicated. The reactions were carried out for 30 mm at 37#{176}C and were stopped by the addition of 400 l of stop solution containing 20 mM HEPES pH 5.5, 2 mM EDTA, and 2 mM EGTA and by placement on ice. [3H} citrulline

was

separated

by

column

above. Reactions were performed expressed as fmol citrulline/mg

Measurement 10

in triplicate, prot/min.

as

and

the

results

was removed ml

of

from

fresh

10-cm

serum-free

dishes

medium

ofcells

were

and was replaced

containing

experimental

cGMP

Dowex

was

isolated

and alumina

ilized,

acetylated,

column

were

were mm.

Each

(36).

bar

ml of medium

in buffer,

at 4#{176}C. The

plasma

centrifuged,

counted

8.0

chromatography.

resuspended

cGMP antibody overnight precipitated with bovine samples

from

Values

represents

I 2%

supernatant

are expressed the mean

was lyoph-

incubated

with

anti-

complex

polyethylene was removed,

as fmol

value

sequential

The eluate and

antigen-antibody

and

the

by

of triplicate

The cells

protl20

Hormone-dependent in Fura-2

easier

Experimental Multiple

groups program

comparisons

Newman-Keuls

were from

compared GraphPad

plates.

among

test. P values

groups


cGMP-sensitive

nLL

=

c\r1

c

C tj:

0

esI

the

levels

with

+1 +1

)

I

2

5)

r1

the

addition

of

results

results

cyclase)

of

Ca

Ca

influx

forskolin-inhibited

Similar

These

+

component

larger,

Ga,3).

z

either

were

demonstrate

was

was

NO

forskolin

to control

cGMP

with

at a step

substantially

restored

or

obtained

that

Ca influx

inhibits

influx

(Figure

cAMP

2C,

analogues.

(activation

of adenylyl

at or before

the production

of NO.

-‘

.-

significance. the NO and

..“

. ‘)

C

‘O

Ca influx, but did not achieve statistical in the cells that express Ga13, in which

clD L,

C

U-

O

>


*

.a ) a C.) n

+1 +1 +1

*

C

c,

I

C

0

z

U #{149}0 s

2Ce

z

.

ai

.-c

(NC

)I

-‘‘-C#

-

(

.n

.5

z

NO express

and

Neo

Gaq

cells

isoforms. and

a minimal

of

the

effect

adenylyl

basal

and

that

express

have

substantially

The

Bradykinin

express

on

cells

that

express

Neo

NOS Ga13.

forskolin

NOS

activity

cells,

activities

activity but it

GaqQ2O9L,

with

cells

to iNOS,

of the

it has no significant the

in the

stimulates

that

In

of iNOS

attributable

be a composite

and

to a much

activity

cells

but

level

is increased

NOS

system

MCT

Ga13 Gaq

bradykinin-stimulated

Ga13,

studied. bNOS,

is primarily

the

of

cAMP-

(eNOS,

in the

cyclase

GaqQ2O9L.

were

production.

it may

and

of NO

Consequently,

cells

that

NOS

Activation

inhibits

both

whole

cells

in

effect

on cells

forskolin

activity

the inhibitory

does not bradykinin.

require

The

mechanism

and

effect

previous

NOS

also

that

inhibits

(Figure

4). These

results

of forskolin

on NOS

activity

activation

+1+1

I

U

and

and

by

activity

activation

of 0 proteins

or NOS

by

,n

ri *

cells

Ga,3,

bition

Q-:’-: +1+1+1

expressing

Ga13

protein

C\1

o=

2T

nase

have

adenylyl

using

cyclase

cell

protein

is reduced

kinase,

protein kinase acute activation

or others)

of NOS

by

activity

Consequently,

:

of

further

of cAMP-dependent

homoge-

kinase

with

bradykinin

is not whole

kinase and

effects

on

that

activation

activity

inhi-

of cells

8-Br-cAMP

inhibit

and

NOS

cAMP-dependent

NOS

NOS (Ga1,

for

in extracts

cells,

do not

proNeo

by 8-Br-cAMP

required

However,

in the

8-Br-cAMP different

70%

indicating

is sufficient to reduce of various G proteins

by cAMP.

expressing GaqQ2O9L. as cAMP-dependent protein

cc

activation

explored

and the catalytic subunit of cAMP-dependent As shown in Figure 5, NOS activity in the

of cAMP-dependent activity and that

...

which was

cAMP-dependent

Gaq.

2Ce

and

NOS

Neo

activity

express

that

in the

cells

‘.-

*

2

Ga13

in the

8-Br-cAMP tein kinase.

n .

cells (19).

express

nates r1

+

.

of iNOS

degree

reduces

C

z


-‘

but

has

oo C-

LI

‘C

iNOS),

Expressing activation

influx

protein

whereas

0 I-

the

express

that

*

*

Ca

activity,

dependent

5) .2 5) 0a t)

inhibits

NOS

-u

in Cells whether

activity.

protein in cells

ki-

expressing

-

c

C C .. c

)n .

U

k.

from

Neo

expression

of

cells

or cells

is not or protein different

expressing

Ga,3.

The

reason

clear, but it may be due to high kinase-C activity in these cells or to accessory

proteins

or

cofactors

for

NOS.

._:

cGMP

g

,..

-Q)

-

C, -.

.

GaqQ2O9L

for this difference phospholipase-C

11

.

n

.

troo

C’JC)

0

5.)

To

.

>izOO

cells

Production determine in a way

in

whether that

Cells cGMP

is consistent

Expressing

Ga13

is regulated with

its regulation

and

by NO of Ca

Gaq in MCT influx,

Inhibition

A.

of NOS

Activity

and

NO-Dependent

Ca

Influx

563

BK

Ca

H4

Thr

TXA2

B.

BK

Ca Thr

TXA2

BK

U

-4---

Ca

Thr TXA2

Figure cells

3. Schematic are shown

Ga1 and Gaq. protein

Potential a chains are

overexpression

representation

in A, cells

that

showing overexpress

the regulation GaqQ2L

activation of Ga,, Gaq, denoted with ‘. Arrows

of G protein

a chains.

In B, where

of NO are shown

and Ca influx in B, and

cells

in MCT that

cells

and Ga13 by thrombin (Thr) or thromboxane show signaling pathways. Heavy arrows

GaqQ2(L

S

expressed,

release

stimulated

overexpress

of Ca from

Gcs,3

with

A, (TXA,) show signaling intracellular

bradykinin

are shown

(BK).

are also shown. pathways that stores

Control

in C. Bradykinin

and

The are

Ca influx

(Neo) activates

expressed activated

G by

are increased

compared with A. However, the importance of the NO- and cGMP-dependent pathways in modulating Ca influx is relatively small, as demonstrated by the findings that their inhibition has little effect on Ca influx. In C. where Ga13 is expressed, iNOS expression is increased, with consequent increases in NO, cGMP, and Ca influx. In these cells, the increased Ca influx can be blocked by inhibition of these pathways and

by cAMP,

which

inhibits

iNOS

activity.

564

Journal

the American

of

Society

of Nephrology

300 C) C

E 0.

C)

200

ci)

Cont.

C

w

BK

V////

Forsk

0 >

C,)

I 00

w z

0

Neo Figure 4. Whole arginine-deficient

a13

aq

in Neo cells and cells expressing GaqQ2O9L and Ga13. Cells were pre-incubated for 15 mm in They were then incubated with bradykinin (BK) l0 M or bradykinin (lO_8 M), and forskolin (l0 M) and IBMX (l0 M), for an additional 10 mm. Parallel samples were incubated with L-NAME (5 mM). The reactions were stopped by the addition of TCA, were extracted with ether, and [3H]citrulline was separated from [3H]arginine by column chromatography (35). Each sample

was

cell assay of NOS activity medium and [3H] arginine.

corrected

for recovery

by the addition

L-NAME-inhibitable

arginine-citrulline

providing

of NOS

a measure

cGMP

production

was

ofapproximately

conversion

activity

activity.

in cpmlmin/mg

measured

under

1200

The activity

conditions

similar

to

Ca influx and NO production in the Neo that express Ga,3 or Gaq Figure 6). In the

control

cGMP

bradykinin dykinin

and

NO.

not

observed

is

83583,

or

level

of

cells,

Stimulation

forskolin.

cGMP

production in

In

production

presence

of

cells

is elevated

that

cells

(approximately

cGMP,

like that of NO, is negligible

or NO.

L-NAME, in

pattern is similar

These

to

agents

in

NO,

inhibit

cells

and

production

the

Neo

that

guanylyl cells

cells

and

express

the

levels

NOS

in

the in

a chains,

activated

by

simultaneously,

A2 contribute

to cell

from ential

each other. regulation

for these

of

and

as well

as others,

Our

higher.

receptors

approach

of

wild-type

or mutant

pathways

they

in the cGMP

by

do not block Ca influx is

cell

functions

were

distinct selective ways

are

Ga,3

such

as

and the

shown

or Gaq.

expressing and cell

are

G

thrombin

acti-

to separate

a chains

selectively

The effects

specific

to differ-

protein

the

chain

the signaling

expressed

a chains

individual

a chains

in Figure

cells

events.

and those of related and tissue injury,

on have

The results are summarized or Ga13-dependent signaling

schematically

on these

a

components of either

activates

ofthe

because

0

of individual Overexpression

and path-

3.

and

cells

we studied bradykinin-stimulated cGMP production, and the effects

cyclase

two

When

difficult

a single

analysis signals.

neomycin-resistant

cause its levels in inflammation

by

receptors.

pathways

effects (14,19,31,33). activation of Gaq

In control,

These

are activated

protein-coupled

control. are

Gaq.

Additionally, they may be subject other signaling processes.

to

inhibited

0

Ga13

by

by

injury,

pathways

these

is blocked

substances

raise cAMP ameliorate cell cells in which individual

expression

many

vated

adenylyl

and thromboxane

the

permits the separation of receptor-generated

Discussion thrombin

of the signaling by

responds

Although 5

by which agents that studied renal epithelial

components

The

GaqQ2o9L

activities

GaqQ2L

by which

represent

and thromboxane receptors (20). Multiple parallel signaling pathways corresponding to different 0 protein a chains are

cGMP

are

cyclase

mechanism injury, we

production, the mechanisms

shown

from the total activity,

LY-

bradykinin.

LY-83583, and forskolin, these agents because the effect of Gaq to increase of this mechanism (14).

To understand

values

protein

increase

express

Ga,3.

The

bra-

to bradykinin

production

cyclase express

that

that

guanylyl

cGMP

that

that

of

solution.

was subtracted

activated

basal

all inhibit

absence but

the

the

forskolin

cells,

that

and

in the

in the

L-NAME, Ca influx, independent

or

and

in the cells

demonstrate and

that

presence production

that

results

bradykinin Neo

the

of cGMP

Ga,3,

in response

and

to the stop

with L-NAME

both

by

above

fourfold),

LY-83583,

by

L-NAME,

express

substantially

control

production

is stimulated

of cGMP the

the

of [‘4Clcitrulline

in the samples

protein.

those used to study cells and in the cells (Neo)

cpm

Bradykinin compounds and because

that

express

Ca influx, of activation

NO of

was

be-

studied are increased it provides

a

Inhibition

of NOS

Activity

and

NO-Dependent

Ca

Influx

565

80 C)

E

70

C

60

E 0.

C)

ci)

50

C

Cont.

I-

w

40

0

PK-A

ci) >

30

C,) C

ci) 0?

20

LU

z

10 0

Neo Figure

5. Measurement

cells

and

cells

of cytosolic

NOS

GaqQ2(L

and

expressing

[3Hlcitrulline

in the absence

[3H]citrulline

was

reliable

Ca signal

influx

requires

mediated

by Gaq.

activation found is

in these

of that

Ca influx

guanylyl

dependent

on

expression

can

In these

intracellular

be modulated and

and

and

cGMP

that

NO

production

influx

by a mechanism

cAMP. cAMP

Additional production

could

the

cells,

ity)

and

activation

processes

In

but

many

of have

NO

through

production. Ca influx

be

increased

is regulated

levels

of NO

they

those

or in the early

(12).

In

influx

some

is difficult

cell

may

explored

stages types,

of

with

those

be

activity

in post-nuclear

by measurement

subunit

of protein

extracts

of conversion

kinase

A. The

of Neo

of [3Hjarginine

reactions

hormone-dependent

full found

of induction the

NO-sensitive

to demonstrate.

Under

influx

induction in the of

cells, are

were

to

stopped,

iNOS

that

of

and low expression levels of NOS (Figure 3). cluding renal epithelial cells, vascular smooth

be

and

cell

proximal

of Ca of Ga,3

In tissues inmuscle cells,

tubules,

tions,

Ca

(2,9).

Excessive

can

synergistically pression

shape,

blockers enter

ATP

phospholipases radicals

(2).

cells

Ca1

NO

by

ability

of

activity

under

transporters

host

tissues,

mechanism that

including

act sup-

activation

generation cells

to

condi-

effects

mitochondria,

ischemic

(40).

injury

pathologic

selective toxic

and

of mul-

metabolism,

of ischemic

multiple by

Ca and

Regardless

control and

a specific,

to injure

proteases,

the

that

that

have

production

and The

may

in cell

Ca1, it is an important

alters

severity

to

could

iNOS.

rises (2,8,9,39).

junctions,

the

demonstrating

with of

tight

of

activation Ga13

to induce

systems

reduce

and

response

to increased

signaling

Amplification

cellular

pathologic

its elevation

as thrombox-

act through

of situations

leads

and

cell

volume,

Ca channel Ca

that

messenger

the

would

of intracellular

iNOS.

that

cytokines

release

induction

of

the

scenario such

the

agents

could enhance

This

to induce

in a number

essential

influx.

in-

expression

could

of substances

with

is

for receptors

INOS

and

of iNOS

to interfere

is valuable

increase

Ga,3,

LPS

with

ability

second cell

Ca

a component

synergistically

of the mechanism

but

of

Additionally,

Ca

circumstances

(the Neo control cells), the NO-sensitive component influx may be small because of low signaling activity

may

the

express of

Ga13

tiple

signals

activate

and

expression

lipopolysaccharide)

Ca

as a consequence

inflammation.

NO

that

presence that

cytokines

by

by cytokines

component

normal

and

iNOS

like ligands

bacterial

on

sustained

Ca,

Ca signals

small

of iNOS, cells

the

or thrombin

The

agents

and

component

Ca

(38).

other

effects

ane

act

/3 cells,

( I 8). Presumably,

cytokines

similar

require

inhibof Gaq

pancreatic

Ga,3,

as

NO-sensitive

in these

In these

activate

have

the

and

by cytokines

that

that

by

studies

of Ca

duced (such

increased

involved

cGMP.

regulation

found

NOS

GaqQ2O9L.

activity

hepatocytes,

We

to inhibition

in these

through

for with

Ga13

but

not sensitive

a component by NO

compatible

degree

kinases

been

required

with

are

was

is

of the Ga1s, such as inhibition of could result in increased iNO activ-

MAP

not

tissues,

influx compared

that

Ca

and

NO-cGMP-Ga,3-dependent

to a smaller

effects (which

and

for NO

and the catalytic

component of Ca influx was inhibited by cAMP. cAMP ited Ca influx by inhibiting NO production. Expression increased

Ga,3

assayed

stores by

cGMP

of hormone-stimulated

NO

of Ga13,

expressing

were

M 8-Br-cAMP

(14,31,33). from

cyclase

the component

cells

extracts

aq

chromatography.

cells

of Ca

in MCT Cell

of l0

by column

release

activity Gr,3.

or presence

isolated

a13

of free to

regulate

of

oxygen their

C 566

Journal

of the American

Society

of Nephrology

a phosphodiesterase

thelial

cell

a number dins E

of

of the

lyl

inhibitor,

injury

clinical

and

ing

6. Measurement

GaqQ2o9L.

Cells

the beginning and

of cGMP

were of the

replaced

with

in MCT

serum-deprived

cells

expressing

24 h before

experiments,

the

culture

fresh medium containing M), NaNO2 (NO 15 mM),

Ga1,

and

medium vehicle bradykinin

was

At

flow

and

the

gastric

removed

mm,

the

medium

was

harvested

and

cGMP, and cell protein was measured. cGMP/mg prot/20 mm. Each value triplicate

frozen

for

Values

measurement

are expressed

represents

the

mean

of as fmol

±

SEM

of

experiments.

phritis

(25).

creased.

PGE,,

sumed

to result

from

Na,K-ATPase could

flow

be

ATP

production

by

whether

variable

Under

normal

absent,

NO

tive

in tissue when

conditions,

that

siveness

of

and

of

increased injury,

those

achieved

tions,

NO

is toxic

(5,7).

High

intestinal epithelial and damage DNA occur teins,

Ca

to

eNOS

tumor

levels

cell monolayers, (7,41). These

that

raise

cell

melanocyte-stimulating

cAMP

injury deter-

(25,29,45).

to epithelial

cells. is

are

by constitu-

regulated

by

reduces

mucus

production

With

Ca

adheof

to inflammation higher

or bNOS.

Under

these

condi-

microorganisms,

the

and

permeability

such

mechanisms

tissue

some

but

hormone,

not

production that

observations,

type

that

that cell

affects

first

injury

and

add

evidence

cell

injury-

occur

through

Agents

cyclase that

are

Ca

regardless

with

in counteracting in

re-

inhibit

required

influx

death

that

may

it simultaneously step

re-

mechanism

reducing Ca

their cAMP

presumably

this

redundant.

pathways

stimulates

Ga,3,

of

adenylyl

for

throm-

cAMP.

injury

Nevertheless,

is an important to

and

of signaling

a mechanism

and

and

by

cell

(18).

receptors

cell

pathway

and

by

effect

iNOS

our findings

another

complex

production activity

through

cytokines

Tissue

NO NOS

that

raise

inflammation

function.

receptor

and

extent

NO

as

cAMP

activity (45). In a cells, MSH acting

as thromboxane

agents by

cells,

induces

by

by stimulating

all

cell

the

of

such

be a tissue-specific

and

of

are

through

to influx of

the

NO

pro-

mechanisms

a variety

of

pathologic

conditions.

host

of

of pro-

Acknowledgments The authors discussions,

for

as misoprostol

to

to inhibit

system,

of

cAMP

such

iNOS

influx.

injury

lead

cells,

inhibits

that

duce

that

reduce ATP production, toxic effects of NO could nitrosylation

also Ca

duction

times

of

To these

preserve in

induction

influx

severity

cAMP

increased or

many

increase

that

low

to levels cells,

of NO

epithelial production

in response

is elevated with

the

levels

(7,1 1,12).

activity

induction

duces

may

in-

the ability

In insulinoma

of iNOS

that,

be blocked

blocks

cyclase

in is

system

inhibition

cells

by activation

explain

and 264.7

induction However,

indicate Ca

will

cyclase

adenylyl

substances

stimulate

effects

of LPS

expression

partially

(25).

muscle

results

elimi-

influx,

increases

tract

through production of peroxynitrite, or by other mechanisms (1,42).

Agents agonist)

GI

NOS NO

than tissues

and

the

that

regulates

bin

may

and in MCT

be

can

expression

at low

on the blood

and

is magnified

iNOS

adenylyl

the

blocks

in smooth

These

(28);

effects

effect

this

where

of the

(29).

inhibitors

reduce and NO

or bNOS)

NO

granulocytes,

cells

or tissue

(eNOS

setting,

because

this

flow

the lethal

iNOS expression cell line, RAW

cAMP

in these

renal

by mecha-

of glomerulone-

inhibited

inflammation

analogues inhibit macrophage-like

cAMP

blood

and

Ga13,

activate

to reduce

cytokines

includ-

reduce

failure

is acutely

system,

ability

proinflammatory

NOS

flow

iNOS

by

depend wherein

injury,

or beneficial when

reduced

in Ca1.

blood

is controlled

of NOS

In this

epithelial

is harmful

production

forms

(5,7).

INOS

NO

and

of NO are complex and of NO. In whole animals,

however,

is pre-

initiated

a rise

nated as a variable, NOS inhibitors (1 ,7). The level of iNOS expression mines

in hypoxia

swelling

exacerbated

is an important injury;

swelling

However,

The cellular effects type and the level

exacerbate

Cell

decreased

activity.

mechanism

cell

(2).

activity

and Ca influx

substances

of

of

(27);

of insults,

(44);

in a model

reduces

express

activity

by

is compromised

NOS

The

NOS

after

(30).

cyclase

that

of rejection suppression

renal

independent

by (and

is independent

drugs

Pentoxyphylline

cells,

cells

a variety

of macrophages

of the adenylyl the

against

of ischemic

to be

permeability

that

immune

in

reduce

Misoprostol

incidence

involves

mucosa

in mice

through

volume

probably

appear

infiltration

In Neo

(BK l0 (BK lOK M and L-NAME 5 x l0 M), bradykinin and LY-83583 (BK 10-8 M and LY 2.5 X l0 M), and forskolin (Forsk l0 M and IMBX 2 x l0 M) and was returned to the incubator. After 20 kinin

that

the

adeny-

IFN-y

and

cAMP

(43).

a mechanism

in models

reduce

stimulate TNF,

cellular

anti-inflammatory

injury

in sepsis

(control), bradyand L-NAME

raise

in

Prostaglan-

in endothelial

reduce by

nonsteroidal

nisms

the experiments.

agonists)

transplantation

tubular

Figure

that

epi-

reactions

situations. of IL-l,

rearrangement

PGE1

preventing

misoprostol)

increases

protect

ccq

Agents

cytoskeletal

blood

a13

and

inflammation-induced

kidney

Neo

(26).

of

inflammatory

production

blocking

other

capable

experimental

(PGE,_3

reduce

macrophages

I!

and

E series

cyclase

are

and of suppressing

(a PGE1

or pentoxyphylline,

measuring

tance. DK39298,

thank Craig

This

cGMP, work

Paul Sternweis

Tisher

was

F32-GM15359,

for

and

and Shmuel

persistent

Paul

supported

McLeroy

for

by grants

GM31954,

Muallem

encouragement,

the

expert

from

for helpful

Susan

the

American

DuBois

technical NIH Heart

assis-

DK41726, Associa-

Inhibition

tion grant

with

funds

from

from

the

Florida

the National

Affiliate

Kidney

(RTM),

Foundation

and

by a training

20.

(KK).

of NOS

Offermanns

family

receptors 1.

21 .

Yu L, Gengaro oxide:

2.

3.

PE, Niedererger

A mediator

1691-1695, D, Almeida

enoff

RA,

Burke

LDH

release

crine

and

ARP, Schrier Am

RW:

JFM,

Ca2+

tubule

J Physiol

II stimulate cells. Clin

Gengaro

uptake,

266:

P. Nem-

fatty

hypoxia:

acid,

Effects

and

23.

1994

24.

Schelling

JR,

Singh

H, Marzec

proximal

tubule

modulation

C1239-C1245, Nathan C, Xie

Linas

sodium

Angiotensin is

C. Am

mediated

J Physiol

oxide

AL:

Roles,

synthases:

and

oxide

con-

in the gut. New

target

8: 33-45,

Horizons

9.

Schrier

RW:

Role

against

experimental

265, 1991 Almeida ARP,

TJ, Schrier channel bule

on anoxia-

I 1.

ture 361: 315-325, Bahnson T, Pandol

Mi:

Inositol

pletion-activated

13.

RA,

and

12653, Darnell

1994 JE Jr.

Ca2+

Kerr

IM,

activation proteins.

proximal

GMP

modulates

acinar

between thesis Pandol cytosolic

TR,

Curran

JB, Di Silvo synthesis

of intracel-

Stark

GR:

Jak-STAT

pathways

to IFNs and 264: 1415-1421,

Si,

release Am

262:

MS:

Cyclic

in the pancreatic

acinar

GMP cell.

477-486, 1990 Nathan C, Xie Q: Regulation

of biosynthesis

18.

J Biol Chem Moms SM,

1994 insights

nitric

269: 13725-13728, Billiar TR: New oxide

synthesis.

oxide

33.

Cell of

34.

free

Calcium nitric

1 1: oxide.

Am J Physiol

the 266:

regulation

of

E829-E839,

1994

19.

35.

36. into

and

Kitamura K, Singer WD, Star RA, Muallem 5, Miller RT: Induction of inducible nitric oxide synthase by the heterotrimeric G protein Ga13. J Biol Chem 271: 7412-7415, 1996

37.

19796-

Organizers

of transmem-

1995

of prostaglandin

ameliorates

E2, dexamethasone,

injury

mac-

in an experimental

glomerulonephritis.

Clin

Vernon-Roberts

misoprostol, functions

B: The

regulates

in vitro

like

prosta-

inflammatory the natural

Exp

cyto-

prostaglan-

B, Pollak rejection

by the prostaglandin

E2 and

E3.

recipients

El

treated

1183-1188,

Paller

JC:

MS,

Manivel and

toxic

RA,

Star

synthase

by

a cellular

GC, Brown form

J. Stock

modulation

PA, Nelson

endotoxic

Kitamura

shock

acid.

RT:

by the

against

mt

R, Catania

R, Lipton

of macrophage

nitric

42:

JM: oxide

PNAS

91:

Regulation

92

line

epithelial

antigen

of an immune

K, Singer

cal-

in renal

epithelial

1994

cell

tubular

inhibition

1994

system

WH, Neilson

target

S: Protec-

of hormone-sensitive

cyclase

NA,

renal

NHE-l

3857-3861,

CJ, Hines

Kefalides

JW, Bursten

by pharmacologic

94: 328-336,

Kelly

RA,

Ri, Singer

adenylyl

Invest

TP,

Amenta EG:

which

PS,

Watanabe

M,

Characterization secretes

experimental

the

of a autologous

interstitial

J

nephritis.

1988

WD,

Cano

in a renal

RT: Gaq

A, Miller

epithelial

cell

line.

and Gal3

Am J Phvsiol

268:

1995 G, Nazarali

AJ, Hermouet

5, Xu N, Gutkind

a subunit

of the Gq protein

induces

NIH

cells.

Biol

3T3 DS,

Molec

Cell

Snyder

SH:

enhancement

of

cGMP

9030-9033,

1989

Hansbrough

JR,

Nitric

Garbers

in

DL:

Speract:

associated

matozoa.

J Biol

256:

A, Busse with

and inhibits

the

R, Liebau release

soluble 1988

glutamate-linked

cerebellum. Purification

with

eggs

1447-1452,

that

5, Forstermann cyclase.

PNAS and

86:

charac-

activates

sper-

1981 U: LY 83583

inter-

relaxation

factor

of endothelium-derived guanylate

in

1992

mediates the

JS: Mutated

transformation

12: 4687-4693, oxide

of a peptide Chem

malignant

levels

terization

283-288,

Kidney

hormone.

in mice

PNAS

K, Miller

influx

feres

kidneys

effect.

a-melanocyte-stimulating

tion

Mulsch

protect

1995

Rice

Bredt

prednisone.

1990

by

N, Huang

of autocrine

Kalinec

in renal-

and

1992

Rajora

Kitamura

misoprostol

cyclosporine

Prostaglandins

injury

Evidence

Haverty

analogue

with

NEnglJMed322:

regulate

1992

269:

M, Mozes

101-110,

biosyn-

regulates

role

Cell Biol 107: 1359-1368,

DL,

and charac-

Cheni

Immunology 76: 251-257. 1992 MF, Maddux MS, Veremis 5, Bartkus C, Ketel R, Wallemark C, Jonasson 0: Prevention of acute graft

El,

Moran

Harper

Differential heterotri-

C1077-Cl082,

The

immune

cells. J Clin 32.

SA: Association

and nitric

and

cium

and

J, Williams

RL, Murray

of cGMP

31.

1995

Stadler

17.

inducible

30.

G

of

SL, Standiford TJ, Burdick MD, Becker AR, Strieter RM: Regulation of neutro-

analogue,

:8016-8020,

other extracel1994

29169-29175, G,

J Phvsiol

Schofield-Payne

calcium

270:

Harbrecht

M, Simmons

by hepatocytes.

El

of phosphatidic

to generate 269: 12645-

Science

and

J Biol

5: Depletion

in response

RD,

de-

cells.

nitric-oxide synthase influx. J Biol Chem

J Biol Chem

G proteins.

29.

Na-

signalling.

Xu X, Kitamura K, Lau K, Muallem 5, Miller RT: regulation of Ca release activated Ca influx(CRAC)by Billiar

tu-

J Biol

G proteins:

infiltration

1345-1354,

1992

calcium

in pancreatic

G, Muallem

activates

Cattell

ischemic

of calcium

526-532,

and

Burke

1993

Tortorici

regulate

effects

V: Cyclic

entry

JFM,

PC: Purification

80: 249-257,

IL-8:

transplant

5A-21S-5A-

hypoxia-induced

trisphosphate 1993 SJ, Dionne

stores

cGMP

Ochoa

16.

90:

protective and

268: 10808-10812,

menc 15.

in protection

M, Wetzels

Exp Ther 260:

Ca2+

transcriptional lular signaling 14.

J Med

D, Burnier

J Pharmacol

Ca2+

blockers

Am

Time-dependent

Berridge

lular

injury.

Bunnachak

blockers

Xu X, Star

channel

28.

10.

12.

calcium renal

RW:

injury.

Chem

of

2 class

J Immunol 151: 2166-2175, 1993 V, Smith J, Cook HT: Prosaglandin El suppresses

dins 27.

1994

by the

IL-4.

kines and related 1994

Cell

WA, Kunkel CA, Gilbert

Wertheim

glandin

1995 8.

signals.

model of macrophage-dependent I,nmunol 79: 260-265, 1990 Haynes DR. Whitehouse MW,

1994

signaling: Nitrosylation oxide. Cell 78: 931-936,

Nitric

tolls,

EJ: Heterotrimeric

by 26.

Nitric

of

thrombin

1996

of Gl3.

rophage

1994

Q:

G: G proteins

91: 504-508,

8: 235-245,

II267:

567

A2 and

Signaling

RT, Sternweis

Neer

and

K, Schultz

PNAS JM:

a subunit

brane

phil-derived

proxi-

Influx

1994

FS, Wilke

25.

SL:

transport

of phospholipase

Stamler JS: Redox interactions of nitric Salzman

R,

human

Miller

of the

Ca

via thromboxane

platelets.

Signalling

WD,

Singer

K, Spicher

N, Dermott Cell

19802,

of mepa-

Fl96-F201,

nitric oxide release from Sci 89: 527-53 1 , 1995

trols. Cell 78: 915-918,

7.

Wetzels

JS, Chatterjee PK, Mistry RP, Weerakody AG, Jardine AG, McKay NG, Hawksworth GM: Atrial natriuretic factor and

cAMP

6.

22.

injury.

in human

terization

proximal

dibucaine.

hypoxia/reoxygenation

NO-Dependent

are activated

Dhanasekeran proteins.

RW: Nitric

1994

RJ,

during

TJ, Schrier

McLay

dependent

5.

in rat tubular

PNAS91: Bunnachak

angiotensin mal tubular 4.

M, Burke

and

5, Laugwitz

the Gl2

References

Activity

J Pharmcol

Exp

Ther

247:

568

38.

Journal

Gupta

5K,

of the

Gallego

constitutively blasts. 39.

American

C, Johnson

activated

J Biol

Weinberg

Chem

JM,

Society

in gip2 267:

Davis

Clapham

DE:

Calcium

Salzman

AL,

Menconi

Gonzalez depletes

PK, Fink ATP

layers. Am 42.

Snyder

SH:

43.

Garcia

JGN,

faces

Schaphorst

is

formation

MA:

Role

of rabbit or acidosis.

Cell

KL:

80: 259-268,

N, Ezzell

oxide

Caco-2BBe of nitric

Karim tiple

oxide.

Regulation

RM,

1995

dilate

tight junctions

intestinal

epithelial

DM,

and

Messmer

UK,

of endothelial

577,

1993 cell

gap

J Invest

misoprostol:

profile.

Kubaszewski muscle

Med Single

43:

1 17-

and

mul-

33:

Prostaglandins

E,

B: Modulation cells.

Peters

Cell A,

release

of

of normotensive

Zhao H, interaction porters

Bruene

in RINm5F

Res Commun 47.

364:

prostaglandin

pharmacokinetic

Light-activated

mono-

1995 Nature

permeability.

40-50,

1987

45. 46.

Casey

peracellular

A: Antiulcer dose

synthase

Unno

Nitric

and

126, 1995 44.

Venkatachalam

J Physiol 268: G36l-G373, Janus

kinase

rat la fibro-

1991

Mi,

MP:

MAP

1992 NF,

signaling.

in cultured

LE:

transformed

calcium in the pathogenesis and protection by glycine

J Clin Invest 87: 581-590, 41.

Heasley src

Roeser

free injury

40.

GL, and

7987-7990,

JA,

of increased cytosolic proximal tubule cell

of Nephrology

McClain nitric

and

in pancreatic

S, oxide

hypertensive

200: 213-218,

Xu X, Ujiie of nitrogen

of inducible

Signalling

Bohr from rats.

D,

oxide

1994 Malinski

vascular Biochem

T:

smooth Biophys

1994

K, Star RA, Muallem oxides and N02 with acini.

nitric

6: 17-24,

Am

J Physiol

267:

5: Transport C02-HCO3-transC385-C393,

and 1994