[Detection and identification of new cardioactive proteins in cattle heart].

Seven cardioactive polypeptides were identified in precardiac and auricular regions of bovine heart. Procedures used for purification of the polypeptides involved extraction of water-soluble proteins, fractionation by ammonium sulfate, gel filtration on Sephadex G-100, chromatography and rechromatography on DEAE cellulose. Some physico-chemical and biological properties were studied; amino acid composition, N-terminal amino acids, molecular mass and the effects on coronary blood vessels. The data obtained suggest that multiple forms of these proteins may exist either as a result of partial hydrolysis of large molecules or due to processing of precursors.