Physiological actions of a family of natriuretic peptides in eels

鳗鱼钠尿肽家族的生理作用

基本信息

批准号：
04640691
负责人：
TAKEI Yoshio
金额：
$ 1.28万
依托单位：
Ocean Research Institute, University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1992
资助国家：
日本
起止时间：
1992 至 1993
项目状态：
已结题

项目摘要

I.We cloned cDNA of eel atrial natriuretic peptide (ANP). The C-terminus of proANP predicted from the cDNA sequence has glycine residue which could not read by the amino acid sequencing. Detailed HPLC analysis revealed that glycine residue was used for amidation of the C-terminus of ANP.Southern blot analysis indicated that ANP and VNP genes are present in birds. Since BNP has already been identified in birds, VNP appears to be a new hormone distinctly different from BNP.II.In cooperation with Professor S.Hirose of Tokyo Institute of Technology, we cloned cDNAs of eel ANP-B and ANP-C receptors. By means of autoradiography and radioligand binding assay, we found dense population of ANP-C receptors in the gill cartilage as well as gill cells.III.Plasma ANP levels increased immediately after transfer of eels from fresh water to seawater. However, in eels adapted to seawater for two weeks, plasma ANP levels decreased significantly from the freshwater levels. The ANP level in the dorsal aorta was decreased to half compared with the level in the ventral aorta, which is explained by the extraction of ANP by ANP-C receptors in the gill.IV.ANP inhibited water intake and intestinal water and sodium absorption in the eel. ANP also caused antidiuresis and increased cortisol excretion. The former actions on the brain and intestine are advantageous to freshwater adaptation, but the latter two actions, antidiuretic and steroidogenic actions, are favorable to seawater adaptation. Thus it is not yet established whether ANP is a freshwater-adapting hormone or seawater adapting hormone in the eel.

i。我们克隆的鳗鱼心房尿液肽（ANP）的cDNA。从cDNA序列预测的POANP的C末端具有甘氨酸残基，氨基酸测序无法读取。详细的HPLC分析表明，使用甘氨酸残基用于ANP的C末端。Southern印迹分析表明，ANP和VNP基因存在于鸟类中。由于BNP已经在鸟类中被发现，因此VNP似乎是一种与BNP.II..在与东京理工学院S.Hirose教授合作的新型激素，我们克隆了EEL ANP-B和ANP-C受体的cDNA。通过放射自显影和放射性结合测定法，我们发现了g软骨中的ANP-C受体密集的人群以及g池。但是，在适应海水的鳗鱼中，血浆ANP水平从淡水水平明显下降。与腹主动脉的水平相比，背主动脉中的ANP水平降低到一半，这是通过gill.iv.iv.anp中ANP-C受体提取的ANP抑制了水的摄入量，肠道水和肠道吸收的ANP-C受体来解释的。鳗鱼。 ANP还引起了抗二硫硫硫次素和皮质醇排泄增加。前者对大脑和肠道的作用对淡水适应有利，但是后两个动作（抗利尿剂和类固醇生成作用）有利于海水适应。因此，尚未确定ANP是鳗鱼中的淡水荷尔蒙还是海水适应激素。