Effects of acetylsalicylic acid (aspirin) and naproxen sodium (naproxen) on ovulation, prostaglandin, and progesterone production in the rabbit.
OBJECTIVE
To determine the effects of acetylsalicylic acid (aspirin) and naproxen sodium (naproxen) on ovulation, ovarian prostaglandins (PG), and P production in the rabbit via in vivo and in vitro studies.


METHODS
Aspirin and naproxen were administered i.v. 6.5 and 7 hours, respectively, after hCG administration to New Zealand White adult female rabbits. Laparotomy was performed 24 hours after hCG administration. For in vitro experiments, control animals underwent laparotomy 6.5 (aspirin) and 7 hours (naproxen) after hCG administration. The treated animal received aspirin and naproxen; laparotomy was performed 1 hour later. One ovary was perfused for 6 hours with aspirin or naproxen whereas the contralateral ovary served as a control and was perfused with control medium (M199; GIBCO, Grand Island, New York). Perfusate samples were collected at 1-hour intervals for PG and P determination.


METHODS
A conventional laboratory setting.


METHODS
In vivo experiments used i.v. administration of 100 mg/kg aspirin and 10 and 50 mg/kg naproxen. In vitro perfusion was also carried out with 100 micrograms/mL aspirin and 10 and 50 micrograms/mL naproxen added to the perfusate.


METHODS
Ovulatory efficiency (no. of ovulations/no mature follicles) and ovarian vein PG and P concentration were determined.


RESULTS
Ovulatory efficiency was 88% for control, 41% for in vivo aspirin-treated, and 40% (10 mg/kg) and 0% (50 mg/kg) for naproxen-treated rabbits. Aspirin and naproxen were associated with decreased ovulatory efficiency when administered in vitro to both in vivo control and in vivo treated ovaries (control-medium = 70%; control-aspirin = 14%; aspirin-medium = 34%; aspirin-aspirin = 0%; control-naproxen = 25%; naproxen-medium = 38%; naproxen = 0% with 10 microgram/mL, and control-naproxen = 13%; naproxen-medium = 0%; naproxen = 0% with 50 micrograms/mL). Prostaglandin F2 alpha was undetectable in the perfusate of those ovaries perfused of those ovaries perfused either with aspirin or naproxen. Ovarian venous concentration of P in the perfusate was similar in all groups.


CONCLUSIONS
Aspirin and naproxen significantly reduced ovulatory efficiency and PG production both in vivo and in vitro in hCG-treated rabbits. A critical period of 6.5 and 7 hours after hCG administration was established.
Zanagnolo
V
V
Department of Gynecology and Obstetrics, Johns Hopkins University, School of Medicine, Baltimore, Maryland, USA.
Dharmarajan
A M
AM
Endo
K
K
Wallach
E E
EE
D000818:Animals; D001241:Aspirin / Q000494:pharmacology*; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D015237:Dinoprost / Q000096:biosynthesis; D005260:Female; D009288:Naproxen / Q000494:pharmacology*; D006080:Ovarian Follicle / Q000187:drug effects; D010053:Ovary / Q000187:drug effects / Q000378:metabolism*; D010060:Ovulation / Q000187:drug effects*; D011374:Progesterone / Q000096:biosynthesis*; D011453:Prostaglandins / Q000096:biosynthesis*; D011817:Rabbits
D006063:Chorionic Gonadotropin; D011453:Prostaglandins; D011374:Progesterone; D009288:Naproxen; D015237:Dinoprost; D001241:Aspirin