Evolution and Adaptation of Gonadotropin Receptors

我们利用哺乳动物、鸟类、两栖动物和鱼类的放射碘化同源促性腺激素，研究了它们对同源和异源物种性腺的特异性弯曲。从这些研究结果可以得出，鱼类具有单一类型的促性腺激素和相应的单一类型的促性腺激素受体，两栖类或至少是无尾两栖类具有FSH和LH两种促性腺激素，但单一类型的促性腺激素或FSH/LH受体，鸟类具有FSH和LH两种促性腺激素，分别对应FSH和LH两种类型的受体。我们还发现了一些证据表明鱼类有多种类型的促性腺激素，但它们与FSH和LH不同源或不相似。我们推测促性腺激素分子分化为FSH和LH发生在两栖动物祖先中，而相应的两种类型受体的分化发生在爬行动物祖先的脊椎动物进化过程中。需要对爬行动物进行进一步的研究。我们还发现，两栖动物的肝脏具有同源物种或类群的促性腺激素特异性受体，这些受体与膜结合腺苷酸环化酶偶联。促性腺激素受体在两栖动物肝脏中的生理作用必须澄清。

We used radioiodinated homologous gonadotropins of the mammal, bird, amphibia and fish, and studied their specific bendings to the gonad of the homologous and heterologous species. From results of these studies, it was concluded that the fish has a single type gonadotropin and corresponding single type gonadotropin receptors, the amphibia or at least the anuran amphibia has two type gonadoftropins of FSH and LH but single type gonadotropin or FSH/LH receptors, and the bird has two type gonadotropins of FSH and LH and corresponding two type receptors for FSH and LH, respectively. We also showed some evidences showing that fish has multiple type qonadotropins but they are not homologous nor analogous to FSH and LH.We postulated that the differentiation of gonadotropin molecules to FSH and LH took place in the ancestral amphibian but the differentation of the corresponding two type receptors took place later in the ancestral reptilian during the course of the vertebrate evolution. Further studies in the retilia are needed. We also found that the liver of amphibians has specific receptors for gonadotropins of the homologous species or group and these recetors are coupled withe the mmbrane-bound adenylate cyclase. The physiological role of the gonadotropin receptors in the amphibian liver must be clarified.