붕어의 난황합성기 여포에서 스테로이드 생성에 관하여

Steroid production by the vitellogenic follicle in silvercarp(carassius auratus)

Gonadosomatic index(GSI) of the silvercarp was investigated to clarified annual reproductive cycle from february to september in 1993. The GSI increased until march and the state of follicle was vitellogenic stage. The GSI fluctuated from april to july, it was evident that spawning of silvercarp occurred in those periods. The GSI decreased from october and the state of follical was atretic stage. Estradiol-17β (E₂) production was examined from vitellogenic follicle to investigated steroid production ability in silvercarp. Isolated follicles were incubated for 18 hours in goldfish Ringer in presence or absence of human chorionic gonadotropin(HCG, 1IU, 10IU) or forskolin(adenylate cyclase stimulator, 0.1 μM, 1 μM, 10 μM) and secretion of E₂ by follicles was measured in media by radioimmunoassay. HCG(1IU, 10IU) and forskolin(0.1 μM, 1 μM, 10 μM) stimulated E₂ secretion and forskolin 10 μM was the most effective in E₂ secretion. The time course of E₂ secretion by follicles was investigated. Isolated follicles were incubated presence or absence of HCG 10IU or forskolin 10 μM from 3 hour to 24 hour. The time course of HCG(10IU) stimulated E₂ secretion was similar to that forskolin(10 μM) stimulated E₂ secretion(3 hrs).