Different time-course production of peptidic and nonpeptidic leukotrienes and prostaglandins E2 and F2 alpha in the ovary during ovulation in gonadotropin-primed immature rats.
Temporal changes in ovarian leukotrienes (LTs) and prostaglandins (PGs) were examined during ovulation to assess roles they may play in this process. Ovulation was induced in immature rats by injection with human chorionic gonadotropin (hCG; 10 IU, s.c.) 2 days after they had been primed with pregnant mare serum gonadotropin (10 IU, s.c.). The ovaries were extirpated at various intervals after hCG administration and assayed for LTB4, and LTC4/D4/E4, as well as PGE2, and PGF2 alpha. Ovarian concentration of LTB4 increased (P < 0.01) rapidly, reaching a peak at 1 hour after hCG administration, then declined (P < 0.05) by 4 hours and remained low thereafter. In contrast, LTC4/D4/E4 peaked (P < 0.01) between 1 and 2 hours, declined (P < 0.05), and then increased (P < 0.01) to achieve a second, larger peak at 10 hours. Prostaglandin E2 increased (P < 0.01) at 6 hours after hCG and did not decrease from the peak value until (P < 0.01) 14 hours after hCG. Concentrations of PGF2 alpha increased (P < 0.01) at 4 hours after hCG, but decreased (P < 0.01) from the peak by 10 hours. Although LTB4, LTC4/D4/E4, PGE2, and PGF2 alpha all increased during ovulation, the time-course differed. This suggests that each eicosanoid may play a distinct role in the process of follicular rupture.
Higuchi
Y
Y
Department of Obstetrics and Gynecology, School of Medicine, Fujita Health University, Aichi, Japan.
Yoshimura
T
T
Tanaka
N
N
Ogino
H
H
Sumiyama
M
M
Kawakami
S
S
D000818:Animals; D015237:Dinoprost / Q000096:biosynthesis*; D015232:Dinoprostone / Q000096:biosynthesis*; D005260:Female; D006062:Gonadotropins / Q000008:administration & dosage*; D015289:Leukotrienes / Q000096:biosynthesis*; D010053:Ovary / Q000378:metabolism; D010060:Ovulation; D011863:Radioimmunoassay; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
D006062:Gonadotropins; D015289:Leukotrienes; D015237:Dinoprost; D015232:Dinoprostone