The angiotensin II antagonist saralasin inhibits ovulation in the perfused rat ovary.
OBJECTIVE
Our null hypothesis was that the angiotensin II antagonist saralasin does not reduce the number of ovulations in the rat ovarian perfusion model.


METHODS
Ovaries from pregnant mare's serum gonadotropin-stimulated immature rats were perfused with nutrient media to which luteinizing hormone and 3-isobutyl-1-methylxanthine had been added to induce ovulation. Test perfusions were treated with saralasin 1 mumol/L (n = 0.5) and compared with controls (n = 5) with the Student t test. Perfusions with both saralasin and angiotensin II and dose-response evaluations were performed.


RESULTS
Saralasin-treated ovulations were 6.6 +/- 1.3 (mean + SEM) compared with 18.6 +/- 3.9, p < 0.02. The effects of saralasin could be reversed with the addition of an equimolar amount of angiotensin II. Dose-response evaluations showed a progressive inhibition of ovulation at 10(-8) to 10(-6) mol/L.


CONCLUSIONS
The angiotensin II antagonist saralasin inhibits ovulation in a dose-dependent fashion; this effect is canceled by the addition of equimolar concentrations of angiotensin II.
Peterson
C M
CM
Department of Obstetrics and Gynecology, University of Utah School of Medicine, Salt Lake City 84132.
Zhu
C
C
Mukaida
T
T
Butler
T A
TA
Woessner
J F
JF
LeMaire
W J
WJ
D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D006064:Gonadotropins, Equine / Q000008:administration & dosage; D010053:Ovary / Q000187:drug effects*; D010060:Ovulation / Q000187:drug effects*; D010477:Perfusion; D051381:Rats; D017207:Rats, Sprague-Dawley; D012504:Saralasin / Q000037:antagonists & inhibitors / Q000494:pharmacology*
D006064:Gonadotropins, Equine; D000804:Angiotensin II; D012504:Saralasin