Jul 8, 1999 - prostaglandin E2 (1.25 mg, 2.5 mg, 5 mg and 10 mg) provokes an increase ... for 30 min, then placebo or one of the prostaglandin E2- dosages.
ELSEVIER
EFFECT OF DIFFERENT DOSES OF PROSTAGLANDIN E2 ON INTRAUTERINE PRESSURE AND UTERINE MOTILITY DURING DIESTRUS IN EXPERIMENTAL COWS G. Hirsbrunner,' R. Eicher,' U. Kupfer,' H. Burkhardt,' and A. Steiner'
'Clinic for Food Animals and Horses, University of Berne 2Dr. E. Graub AG, Berne, Switzerland Received for publication: July 8, 1999 Accepted: October 25, 1999 ABSTRACT Studies in human medicine proved the important role of prostaqlandln E2, which stimulates uterine contractions in vivo and in vitro and has been extensively used to ripen the cervix around labor. We wanted to demonstrate that increasing the dosage of prostaglandin E2 (1.25 mg, 2.5 mg, 5 mg and 10 mg) provokes an increase in intrauterine pressure and uterine motility in cattle. Five healthy, lactating dairy cows were used as experimental animals for this study. Intrauterine pressure was recorded during the diestrus phase (1 recording per cow and diestrus phase) by means of a transcervically placed intraluminal pressure microtransducer. Physiologic uterine motility was recorded for 30 min, then placebo or one of the prostaglandin E2- dosages was administered through an indwelling catheter in the jugular vein, followed by a 2-h recording period (eight 15-min periods). Area under the curve (AUC), mean amplitude, frequency of pressure waves and intrauterine pressure were analyzed. Furthermore, we recorded protocols for monitoring heart and respiratory rates and side effects at 9 given examination times. Significant differences were found for the AUC, the mean amplitude and the intrauterine pressure (P ~ 0.05), whereas the number of pressure waves per 15 min did not differ significantly among treatments. Peak values for AUC, mean amplitude and intrauterine pressure were found during the first 15 min after administration of 10 mg of prostaglandin E2. Dose-effect curves showed that the 2.5 mg dosage provided the optimal ratio between myometrial stimulation and undesirable side-effects. © 2000 by Elsevier Science Inc.
Key words: cow, uterus, pressure, prostaglandin E2
Acknowledgments We thank Dr. E. Graub AG for supporting this study; Mr. F. Baumgartner for care of the cows; and finally, we thank the 5 experimental cows: Sara, Kuba, Helga, Vroni and Verita for their gentle patience. Theriogenology 54:291-303, 2000
© 2000 Elsevier Science Inc.
0093-691 X1oo/$-see front matter PII: S0093-691X(00)00349-6
Theriogenology
292 INTRODUCTION
In herd management, PGF2
