催乳素及其受体样免疫活性在文昌鱼神经系统、哈氏窝和其它组织的分布

Distribution of prolactin and its receptor-like immunoreactivities in the nervous system,Hatschek's pit and other tissues of the amphioxus Branchiostoma belcheri

用兔抗人催乳素多克隆抗体和鼠抗人催乳索受体单克隆抗体对文昌鱼神经系统、哈氏窝和其它组织进行免疫组织化学研究。结果显示:催乳素免疫活性细胞及催乳素受体定位在文昌鱼脑泡、神经管、哈氏窝、轮器、内柱、消化管和性腺(卵巢和精巢),表明催乳素在文昌鱼有广泛分布,并且从进化观点来看,证明催乳素是一种高度保守的古老激素。双重免疫染色进一步揭示催乳素及其受体免疫反应阳性物质共存于同一卵母细胞胞膜和胞质以及精巢中精原细胞、初级与次级精母细胞和Sertoli细胞。研究结果首次证明了文昌鱼脑泡和哈氏窝以及其它组织能够合成和分泌催乳素,表明像脊椎动物一样,催乳素可能参与调节文昌鱼体内代谢和对环境的适应以及性腺发育,提示文昌鱼可能出现原始的脑泡-哈氏窝(催乳素)-靶细胞调控轴的雏形。本研究为文昌鱼哈氏窝内分泌学以及催乳素的起源与演化提供新的基础资料。

Immunohistochemical studies on the nervous system, Hatschek＇s pit and other tissues of amphioxus Branchiostorna belcheri were performed by using rabbit anti-prolactin （human） polyclonal antibody and mouse anti-prolactin receptor （human） monoclonal antibody. The results showed that prolactin-like immunoreactive cells and prolactin receptor were extensively localized in the brain vesicle, nerve tube, Hatschek＇s pit, wheel organ, endostyle, digestive tract and gonads （ovary and testis）. These observations support the view that prolactin is an ancient and highly conserved hormone. Double staining further revealed that the immunoreactivity of prolactin and its receptor co-existed in the cellular membrane and cytoplasm of the same oocytes and spermatogonia, primary and second spermatocytes as well as in Sertoli cells. The present data demonstrated for the first time that brain vesicle and Hatschek＇s pit and other tissues of amphioxus could synthesize and secrete prolactin. This suggests that prolactin may be involved in regulating metabolism, adaptation to the environment and gonadal development in amphioxus, as in other vertebrates. The present study provides new basic information on the endocrinology of Hatschek＇s pit and the origin and evolution of prolaetin .