Pathological Changes in the Viscosity of Blood Serum.

Measurements of the viscosity of blood serum reported by clinical observers have shown results that are seemingly paradoxical. We have attempted to investigate the physical-chemical basis of these empirical relationships.Blood serum, as seen from the viscosity at different dilutions, shows a remarkable ability to keep its viscosity constant in spite of dilution. If we compare the effects of dilution on the viscosity of such a protein as gelatine, we find that not alone is the absolute viscosity of the same percentage concentration of serum protein very much lower than that of a similar strength of gelatin, but the gelatin manifests a much greater change in viscosity for each increasing unit of dilution. The importance of this point in maintaining the circulation of the blood in such conditions as nephrosis, where the blood proteins are reduced to one half their normal concentration, is obvious.Loeb has distinguished between two types of protein, one represented by gelatin and the other by egg albumin. In ...