PREPARATION AND CHEMISTRY OF ANTERIOR PITUITARY HORMONES

Abstract

The hormones of the anterior pituitary gland are proteins. On the basis of the physiological evidence, there appear to be at least 6 recognized individual hormones, although there is some biologic overlapping among certain of the ant. pituitary secretions. The existence of other hormones in the ant. pituitary gland is not yet completely excluded. Four of the protein hormones have been isolated in a homogeneous and highly purified state as judged by the application of electrophoretic, ultra-centrifugal, and solubility techniques, although the use of other criteria of establishing purity, e.g., biologic assays and immunologic behavior, may reveal impurities not detectable by physico-chemical methods. The four most highly purified ant. pituitary proteins are the lactogenic, the adrenotrophic, the growth and the luteinizing hormones. The thyrotrophic principle has been isolated in highly purified form, but has not yet been examined by rigid criteria of protein purity. The follicle-stimulating hormone awaits further purification. The author makes a few remarks on the relation of the structure of these hormones to their biologic activity.