OCCURRENCE OF THREE ELECTROPHORETIC COMPONENTS WITH MELANOCYTE-STIMULATING ACTIVITY IN EXTRACTS OF SINGLE PITUITARY GLANDS FROM UNGULATES

Abstract

An in vitro method in which the skin of a single test animal (Anolis carolinensis) is used, and which can be used to determine the melanocyte-stimulating activity of a large number of samples, is described. The electrophoretic behavior of the melanocyte-stimulating components present in the pituitary glands of different species of Ungulata was studied. It was found that single beef, pig and sheep pituitaries contain three melanocyte-stimulating components, which behaved in electrophoresis like β-glutamyl-MSH, β-seryl-MSH and a-MSH respectively. These MSH components were present in each single pituitary gland in a ratio which appeared to be more or less constant within a species and which was characteristic for that species.