MECHANISMS IN EXPRESSIONS OF TWO FORMS OF VITELLOGENINS IN FISH

最近在日本虾虎鱼中发现了两种卵黄蛋白原（Vg）。在本研究中，我们利用肝培养系统研究了两种形式的Vg的激素调节。用男性和女性肝脏切片进行器官培养进行分析。不同剂量雌二醇-17β (E2)孵育7天后，采用新开发的酶联免疫吸附法测定各Vg （530kVg和320kVg）在培养基中的Vg水平。在男性肝脏中，E2产生了几乎相同数量的530k和320kvg，并呈剂量依赖性。相比之下，卵黄形成期女性肝脏中这两种Vgs的水平明显高于男性肝脏，尽管检测到的530kVg是320kVg的2-3倍。此外，不含E2的雌性肝脏产生的两种Vgs水平与含E2的雌性肝脏产生的Vgs水平无显著差异。这些结果表明530kVg和320kVg的调控是不同的。

Recently, two forms of vitellogenin (Vg) were found in Japanese goby. In this study, we investigated the hormonal regulations of the two forms of Vg using liver culture system.Organ culture with slices from both male and female liver was attempted for the analyses. The Vg levels were measured inculture media by newly developed specific enzyme-linkedimmunosorbent assay for the each Vg (530kVg and 320kVg) after the incubation for 7 days with various doses of estradiol-17β (E2).In male liver, almost the same amount of 530k and 320kVgwere produced in response to E2 in dose dependent manner. Incontrast, the levels of both Vgs in female liver at vitellogenic stage were apparently higher than those in male liver, although 2-3fold 530kVg was detected as compared with 320kVg. Inaddition, the levels of both Vgs produced by the female liver incubated without E2 were not significantly different from those with E2.These results suggest that 530kVg and 320kVg were regulated differentially.