Role of interleukin-1beta in superovulation in rats.
In this study, the changes in interleukin-1beta (IL-1beta) mRNA expression and its localization in the ovary were studied in pregnant mares' serum gonadotropin (PMSG)-human CG (hCG) injected immature rats. Moreover, to study the in vivo role of IL-1 during ovulation, the IL-1 receptor antagonist (IL-1ra) was injected into the bilateral bursae (100 microg/15 microl/bursa) immediately or at the 3rd, 5th, 10th h after hCG injection. IL-1beta mRNA expression in the ovary had significantly (P<0.05) increased at the 6th h after hCG injection, and its level depended on the time interval between PMSG and hCG injections; the maximal IL-1beta mRNA expression was observed when hCG was injected 48 h after the PMSG injection. The signals of IL-1beta mRNA localized in the thecal layer, particularly in the large preovulatory follicles. Intrabursal IL-1ra injection at the 3rd h after hCG injection showed a trend toward lowering the number of ova shed, and the injection at the 5th h significantly (P<0.01) decreased the number of ova shed compared with the saline injected control group. At the 24th h after hCG injection, there were a few large preovulatory follicles with distinguishable theca and granulosa layers in the IL-1ra treated ovary, although these two layers were indistinguishable in the control ovary. These results indicated that IL-1beta mRNA expression was definitely induced by hCG stimulation, and, moreover, this expression was dependent on the stage of follicular maturation. IL-1 may be important for the ovulation in the superovulatory cycle by PMSG in rats.
Ono
M
M
Department of Obstetrics and Gynecology, Yamaguchi University School of Medicine, Kogushi, Ube, Japan.
Nakamura
Y
Y
Tamura
H
H
Takiguchi
S
S
Sugino
N
N
Kato
H
H
D000818:Animals; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D005260:Female; D006064:Gonadotropins, Equine / Q000494:pharmacology; D007375:Interleukin-1 / Q000235:genetics / Q000502:physiology*; D006080:Ovarian Follicle / Q000187:drug effects*; D010053:Ovary / Q000187:drug effects / Q000502:physiology*; D012333:RNA, Messenger / Q000096:biosynthesis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017472:Receptors, Interleukin-1 / Q000037:antagonists & inhibitors; D013480:Superovulation / Q000502:physiology*
D006063:Chorionic Gonadotropin; D006064:Gonadotropins, Equine; D007375:Interleukin-1; D012333:RNA, Messenger; D017472:Receptors, Interleukin-1