Conlon J M, Collin F, Chiang Y C, Sower S A, Vaudry H
Department of Biomedical Sciences, Creighton University Medical School, Omaha, Nebraska 68178.
Endocrinology. 1993 May;132(5):2117-23. doi: 10.1210/endo.132.5.8477660.
The molecular forms of GnRH in amphibia have not been characterized structurally. An antiserum to mammalian GnRH that shows appreciable cross-reactivity with chicken GnRH-I ([Gln8]GnRH), chicken GnRH-II ([His5,Trp7,Tyr8]GnRH), and salmon GnRH ([Trp7, Leu8]GnRH) was used in a RIA to detect GnRH-related peptides in an extract of the brain of the European green frog, Rana ridibunda. Two peptides were purified to apparent homogeneity, and determination of their primary structures showed that they are identical to mammalian GnRH and chicken GnRH-II. Salmon GnRH and lamprey GnRH-I ([Tyr3,Leu5,Glu6,Trp7,Lys8]GnRH) were not identified in this species of frog. Immunocytochemical analysis using specific antisera has identified regions of the frog diencephalon and telencephalon in which chicken GnRH-II and mammalian GnRH are localized to different populations of neurons. This differential distribution suggests distinct physiological roles for the two forms of GnRH in amphibia.
两栖动物中促性腺激素释放激素（GnRH）的分子形式尚未在结构上得到表征。一种针对哺乳动物GnRH的抗血清，它与鸡GnRH-I（[谷氨酰胺8]GnRH）、鸡GnRH-II（[组氨酸5、色氨酸7、酪氨酸8]GnRH）和鲑鱼GnRH（[色氨酸7、亮氨酸8]GnRH）有明显的交叉反应，被用于放射免疫分析（RIA），以检测欧洲绿蛙（林蛙）大脑提取物中的GnRH相关肽。两种肽被纯化至表观均一，其一级结构的测定表明它们与哺乳动物GnRH和鸡GnRH-II相同。在这种蛙类中未鉴定出鲑鱼GnRH和七鳃鳗GnRH-I（[酪氨酸3、亮氨酸5、谷氨酸6、色氨酸7、赖氨酸8]GnRH）。使用特异性抗血清的免疫细胞化学分析已确定了蛙间脑和端脑中鸡GnRH-II和哺乳动物GnRH定位于不同神经元群体的区域。这种差异分布表明两种形式的GnRH在两栖动物中具有不同的生理作用。
