A Rat Serum Protein related to Reproduction, Tissue Synthesis and Lactation

Abstract

DARCY^1,2 has demonstrated by immunoelectrophoresis the presence of a protein in the sera of fœtal, neonatal, pregnant, tumour-bearing and regenerating rats not found in the sera of healthy, non-pregnant adults of either sex. More recently, Beaton et al.^3,4 and Heim⁵ have shown, in the sera of pregnant and neonatal rats, the existence of a distinct protein component in the electrophoretic pattern obtained by starch-gel electrophoresis which is absent from the patterns of sera from healthy, non-pregnant, adult rats. Beaton et al.⁴ also demonstrated this component in certain pathological conditions and Heim⁵ found it in sera from fœtal and lactating rats. The presence or absence of the new component, hereinafter termed reproduction-associated protein, has now been determined over most of the life-cycle of the rat and under certain experimental conditions. A hypothesis of identity of the reproduction-associated protein with the protein discovered by Darcy¹ is suggested.