STUDIES ON PITUITARY LACTOGENIC HORMONE : III. SOLUBILITIES OF SHEEP AND BEEF HORMONES

The solubility of sheep pituitary lactogenic hormone in 0.302 M NaCl at pH 2.02 (solution in HCl) has been determined at room temperature. It showed a constant solubility in the presence of a considerable excess of the solid phase, an indication that the preparation contained but one component. Beef lactogenic hormone showed a constant solubility in distilled H(2)O at 7–8°C in the presence of excess of the solid phase. The salting-out effect of NaCl in acid solution of both beef and sheep hormones has been studied at room temperature. In these studies both preparations behaved as pure substances, but they exhibited differences in solubility, thus indicating a species specificity.