Serum Albumin

Abstract

The significance of HSA as a steroid binder in the circulating blood has been emphasized in Vol. I. Although the affinity constants of steroid hormone complexes with albumin may be orders of magnitude lower than the K_a values of the association with the specific high-affinity binders in the serum, the greater concentration of albumin causes a large portion of the steroids to form complexes with the lower-affinity binding sites of the albumin molecule. The capacity of this binding system is always far in excess of any concentration of endogenous or exogenous steroids ever encountered in the blood stream. An example of the importance of albumin for the steroid binding distribution in the blood serum may be seen in Chapter VII.J.4 and Tables VII-23 and VII-24.