Endocrinological analysis of amphibian life cycle

两栖动物生命周期的内分泌分析

基本信息

批准号：
01440005
负责人：
KIKUYAMA Sakae
金额：
$ 15.62万
依托单位：
Waseda University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (A)
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1992
项目状态：
已结题

项目摘要

Endocrinological analysis of biological phenomena such as metamorphosis, growth and reproduction in amphibian life cycle were performed. 1)Metamorphosis Amphibian metamorphosis is mainly under the control of three hormones, namely, thyroid hormone, adrenocortical hormone and prolactin. Our study was focused on prolactin gene expression during metamorphosis. Using bullfrog and toad prolactin cDNA, we have revealed that prolactin mRNA levels rise as metamorphosis progresses. This indicates that the elevation of plasma and pituitary prolactin levels during metamorphic climax accompanies the elevation of prolactin synthesis. The enhacement of prolactin cell function in the pituitary during metamorphic climax is presumed to be related with the maturation of adult organs which develop in this period. In fact, we have demonstrated that prolactin increases phospholipids in the lung surfactant. 2)Growth We have purified amphibian growth hormone from the bullfrog pituitary. Using this preparatio … More n, primary structure of amphibian growth hormone was determined. Homologous radioimmunoassay system was also developed. It was revealed that growth hormone levels rise as metamorphosis progresses and reaches maximum when the animals completed metamorphosis. Growth hormone mRNA levels are also high in the juvenile frogs. This indicates that in juveniles a marked growth occurs. As regards the mode of action of growth hormone, presence of a growth hormone mediator in the plasma, as in the case in mammals, was demonstrated in Xenopus. 3)Reproduction Hormonal control of courtship behavior in the newt, Cynops pyrrhogaster was studied. Sexually mature male of this species vibrates the tail in front of sexually mature female at the initial stage of courtship. It was reveled that both incidence and frequency of the tail vibration behavior are enhanced by prolactin and androgen (testosterone or dihydrotestosterone). Moreover the male releases a sex attractant into the water. It was revealed that the attractant is secreted from the abdominal glands of the cloaca. The development of the abdominal glands is also under the control of prolactin and androgen. It was demonstrated that this attractant is a peptide of molecular weight below 5,000. Less

对两栖动物生命周期的变态，生长和繁殖的内分泌现象分析。在变质高潮期间的血浆和垂体催乳素水平伴随着催乳素SI的升高。垂体的垂体。 Xenopus。在最初的求爱时，在性成熟的女性面前研究了对Therhogaster的荷尔蒙行为。腹部腺体也位于催乳素的控制下。