长吻鮠人工催产及脑垂体促性腺激素细胞的超微结构的变化

通过对催产和未催产的长吻鮠脑垂体中腺垂体促性腺激素分泌细胞（ＧＴＨ 细胞） 的分泌活动分析，证实了用促黄体素释放激素类似物（ＬＲＨ－ Ａ） ５０μｇｋｇ 加ＤＯＭ５ｍｇｋｇ 混合注射催产长吻鮠，能有效地促使ＧＴＨ细胞分泌促性腺激素，诱导卵母细胞成熟和排卵，催产效果显著。超微结构的进一步观察，揭示了长吻鮠脑垂体ＧＴＨ 细胞中存在两种分泌颗粒，即分泌小球，直径１２００～２０００ｎｍ ，电子密度低；分泌颗粒直径３００ ～５００ｎｍ ，电子密度高。分泌小球释放与卵母细胞的发育成熟有关，分泌颗粒的释放则与排卵相关。

ARTIFICIAL INDUCED SPAWNING OF LEIOCASSIS LONGIROSTRIS AND CHANGE OF ULTRASTRUCTURE OF HYPOPHYSIS GTH CELL

By the secretory action analysis of hypophysis gonadotropic hormone ( GTH ) cell of long snout catfish (Leiocassis longirostris ) captured in the estuary of Changjiang River, it was verified that combinative injection of LRH-A 50ug/kg and DOM 50mg/kg could stimulate the secretion of GTH, induce the maturation and ovulation of oocyte. The results also indicate that there are two kinds of secretory granules in the GTH cell, one granule is bigger with diameter about 1 200-2 000nm and lower electron density; the other one is smaller with diameter about 300-500nm and higher electron density. The release of bigger granule (secretory gloube) was relative to development and maturation of oocyte while the release of smaller granule (secretory granule) was relative to ovulation.