THE EXTRACTION OF PROLACTIN FROM HUMAN PITUITARY GLANDS

Abstract

A method for the extraction of prolactin from human pituitary glands is described. It is based on acetone drying, distilled water extraction, acetone and isoelectric precipitation. Two main products are obtained: Fraction R8 with a mean prolactin activity of 12.2 IU/mg and fraction U8 with a mean prolactin activity of 8.6 IU/mg. The former fraction does not contain any significant gonadotropin activity and the latter contains on an average 50 HMG (human menopausal gonadotropin) U/mg. In both cases contamination with ACTH and MSH (melanocyte-stimulating hormone) is minimal. The growth hormone activity of both these fractions is low. It is postulated that in man too, prolactin and growth hormone are 2 distinct hormones. A total of 1250 human pituitary glands have been processed by this method. The mean prolactin content per pituitary gland has been found to be 73 IU.