[Heterogeneity of pituitary gonadotropin from sturgeons].

A highly purified preparation of the pituitary gonadotropin of a chondrostean fish, sevryuga (Acipenser stellatus Pall.) has been shown to be homogeneous by criteria of molecular weight, sedimentation coefficient and by N-terminal amino acid analysis. On the contrary, polyacrylamide gel electrophoresis and isoelectric fucusing have revealed a marked heterogeneity of the hormone preparation. The determination of gonadotropic activity (in vitro amphibian oocyte maturation test) has shown the similar specific activities of the differently charged hormone molecules.