Short Communication Mediators of Inflammation, 7, 409–411 (1998)
THE airw ay ep ith e lium is r es p on s ible fo r th e p r oduction of a n um be r of ar ach ido nic acid an d n on p r os tan oid in h ibitory fa cto rs . Ep ith elium s ynth e s is es n itric ox ide (NO) w h ic h m ay be im p o rtant in r egulatin g th e function of air w ays s m o oth m uscles . We s tudie d in vitr o th e effe ct of h is tam in e (100 n M– 100 m M) w h ic h in cr eas es th e NO r eleas e on rabbit airw ay s m oo th m uscles in duced by 80 m M KCl in th e p r es e nce o r n ot of 10 – 5 Me th ylen e blue (MB) (in activato r o f guan ylate cyclas e ) o r N(G)-m on om e th yl L-argin in e (L-NMMA), a NOS in h ibitor. All ex p er im en ts w e re don e in trach e al m uscle s trip s fr om 28 rabbits w ith ep ith e lium and after ep ith elium r em o val. Th e addition al use o f h is tam in e (1 m M) on KCl con traction in duce d a r e lax ation o f 10% of th e in itial con traction . Th e addition al us e of L-NMMA de cr eas ed th e re lax atio n to 5% o f in itial con tractio n. MB r ath e r th an L-NMMA in cr e as ed th e con traction s ignificantly (p
