Clomiphene citrate inhibits gonadotropin-induced ovulation by reducing cyclic adenosine 3',5'-cyclic monophosphate and prostaglandin E2 levels in rat ovary.
OBJECTIVE
To determine whether clomiphene citrate (CC) inhibited gonadotropin-induced ovulation by reducing cyclic adenosine 3',5'-cyclic monophosphate (cAMP) and prostaglandin E2 (PGE2) levels in ovary. If so, to determine whether E2 coadministration could protect against these effects of CC.


METHODS
A controlled prospective study.


METHODS
Laboratory research setting in the department of reproductive biomedicine at a national research institute in India.


METHODS
Sixty sexually immature female rats that were 24-25 days of age.


METHODS
The sexually immature female rats were given a single injection (10 IU i.m.) of pregnant mare serum gonadotropin. After 48 hours, the rats were given single injections of hCG (10 IU) along with CC, with or without E2, for 16 hours.


METHODS
Number of superovulated COCs, ovary and uterus weight, FSH and LH levels in serum, and cAMP and PGE2 levels in ovary.


RESULTS
The superovulatory dose of gonadotropins significantly increased ovary and uterus weights, cAMP and PGE2 levels in ovary, and serum levels of FSH and LH. Coadministration of CC (10 mg/kg body weight) significantly reduced levels of cAMP, PGE2 in the ovary, ovary and uterus weights, and ovulation rate, whereas FSH and LH levels were not significantly altered. Supplementation of E2 protected against these inhibitory effects of CC and augmented levels of FSH and LH in serum.


CONCLUSIONS
Clomiphene citrate inhibited gonadotropin-induced ovulation by reducing cAMP and PGE2 levels in the ovary, and E2 protected against these effects of CC on gonadotropin-induced ovulation in rat.
Chaube
Shail K
SK
Department of Reproductive Biomedicine, National Institute of Health and Family Welfare, Munirka, New Delhi, India.
Prasad
Pramod V
PV
Tripathi
Vinay
V
Shrivastav
Tulsidas G
TG
D000818:Animals; D002996:Clomiphene / Q000494:pharmacology*; D000242:Cyclic AMP / Q000037:antagonists & inhibitors* / Q000378:metabolism; D015232:Dinoprostone / Q000037:antagonists & inhibitors* / Q000378:metabolism; D004958:Estradiol / Q000494:pharmacology; D004965:Estrogen Antagonists / Q000494:pharmacology*; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D006062:Gonadotropins / Q000494:pharmacology*; D007986:Luteinizing Hormone / Q000097:blood; D009929:Organ Size / Q000187:drug effects; D010053:Ovary / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism*; D010060:Ovulation / Q000187:drug effects*; D010062:Ovulation Induction; D051381:Rats; D017207:Rats, Sprague-Dawley; D014599:Uterus / Q000033:anatomy & histology
D004965:Estrogen Antagonists; D006062:Gonadotropins; D002996:Clomiphene; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D000242:Cyclic AMP; D015232:Dinoprostone