COMPARATIVE POTENCY OF GROWTH HORMONE PREPARATIONS IN ALKALI OR ACID

Abstract
Growth hormone preparations obtained from beef pituitary through alkali extraction (methods of Li and Wilhelmi) were compared for growth activity in hypophysectomized rats with acid extracted porcine growth hormone (method of Raben). The alkali extracted preparations showed reduced activity when assayed in acid media. The reduced potency was shown to result from storage at the acid pH, rather than from inactivity at the time of injection. Hydrochloric acid was shown to be more damaging than acetic acid of comparable pH. Somatotropic preparations obtained from beef or pork pituitary through acid extraction showed no difference when assayed in basic or acidic media. It was concluded that the differential effect of pH on Li or Wilhelmi growth hormone as compared to Raben type preparations is not due to the gland source, but rather to the method of preparation.
Keywords

This publication has 5 references indexed in Scilit: