Riley Larry G, Hirano Tetsuya, Grau E Gordon
Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe 96744, USA.
Zoolog Sci. 2002 Jul;19(7):797-800. doi: 10.2108/zsj.19.797.
Recently, ghrelin (Ghr), a new peptide which specifically stimulates growth hormone (GH) release from the pituitary, was identified in the rat and human stomach. Ghrelin has been shown to stimulate GH release by acting through a growth hormone secretagogue (GHS) receptor in the rat. The present study describes the in vitro effect of rat Ghr on the release of GH and two forms of prolactin (PRL(177) and PRL(188)) in the tilapia, Oreochromis mossambicus. Rat Ghr stimulated the release of GH in a dose-related manner after 8 and 24 hr of incubation. Rat Ghr also significantly stimulated the release of PRL(177) and PRL(188) in a dose-related manner after 24 hr. Rat Ghr had no effect on the pituitary content of GH or PRL(188), but significantly increased PRL(177) content. These results show for the first time that rat Ghr significantly stimulates GH and PRL release in teleosts, and suggest that Ghr and a GHS receptor are present in fish.
最近，一种新的肽——胃饥饿素（Ghr）在大鼠和人类胃中被发现，它能特异性刺激垂体释放生长激素（GH）。胃饥饿素已被证明在大鼠中通过生长激素促分泌素（GHS）受体发挥作用来刺激GH释放。本研究描述了大鼠Ghr对罗非鱼（莫桑比克罗非鱼）GH释放以及两种形式催乳素（PRL(177)和PRL(188)）的体外作用。孵育8小时和24小时后，大鼠Ghr以剂量相关的方式刺激GH释放。孵育24小时后，大鼠Ghr也以剂量相关的方式显著刺激PRL(177)和PRL(188)的释放。大鼠Ghr对垂体中GH或PRL(188)的含量没有影响，但显著增加了PRL(177)的含量。这些结果首次表明，大鼠Ghr能显著刺激硬骨鱼的GH和PRL释放，并提示鱼类中存在Ghr和GHS受体。
