Comparison of the activities of two purified fish gonadotropins on adenyl cyclase activity in the goldfish ovary

Abstract

The pituitary gonadotropin from a Pacific salmon (Oncorhynchus tshawytscha) stimulates adenyl cyclase activity in homogenates of ovaries from goldfish (Carassius auratus) but it is about 36 times less active than carp (Cyprinus carpio) gonadotropin. Moreover, a higher maximal stimulation of the cyclase is obtained with the more homologous (carp) gonadotropin. These results suggest the existence of a partial zoological specificity of teleost gonadotropins in their stimulating action on adenyl cyclase.