鲤鱼脑垂体中促性腺激素含量的周年变化

ANNUAL CYCLE OF GONADOTROPIN CONTENT IN COMMON CARP (CYPRINUS CARPIO L.) PITUITARY GLAND

经丙酮干制的垂体粉用40％乙醇抽提,冷冻干燥,用放射免疫测定法测定鲤鱼垂体中促性腺激素含量的周年变化。年平均含量为56.1微克/毫克。2月份临近产卵期时,雌、雄鲤鱼垂体中的促性腺激素含量都达到最大值(雌鱼为 154.0微克/毫克,雄鱼为 160.0微克/毫克)。雄鱼 9月份含量最低(8.3微克/毫克),雌鱼 10月份含量最低(3.8微克/毫克),并分别在 10月份和11月份后开始逐渐上升。其周年变化并与其性腺的发育成正相关关系。

A radioimmunoassay (RIA) for annual cycle of gonadotropin (GTH) pituitarycontent in common carp has been made. Carp pituitary glands dried by acetone wereextracted with 40% ethanol and lyophilized for assay. The annual mean content ofgonadotropin in pituitary gland is 56.1μg/mg. GTH pituitary content of both maleand female reach to maximum value in February near the ovulation stage (female154.0μg/mg; male 160.0μg/mg). While GTH pituitary content of male fish inSeptember and that of female in October drop to minimum value 8.3μg/mg for maleand 3.8μg/mg for female. Later on the contents of both male and female begin toincrease gradually until a maximum value is reached again in next February. Seasonalvariation of the GTH contents exhibit a definite cycle change and it is positively cor-related with gonadosomatic index (GSI).