Experimental Edema—Further Observations on the Plasma Proteins and Blood Cholesterol.

Abstract

Since the first report, in 1928, 1 of the experimental production of edema in dogs by the method of plasmapheresis, further work has been carried out, the results of which are given in this preliminary report.

Edema has been produced in about 40 dogs, often several times in the same dog, whenever the plasma protein level has been maintained at about 3 gm. % or below. Above this level, edema disappeared promptly. There has been essentially no exception among the dogs used.

Several factors have been controlled. Cardiac damage has been ruled out by bleeding a series of dogs from the external jugular veins. Starvation alone, or with the daily administration of 1500 cc. of saline by stomach tube, gives rise to no significant change in the concentration of the plasma proteins nor to visible edema. The alkalinity of the modified Locke's solution used as a suspending medium for the erythrocytes injected into the dog plays no important rôle.

The regeneration of the plasma globulin is much more rapid than that of the plasma albumin and accounts for most of the sharp rise in the total protein when plasmapheresis is discontinued. This is shown best in the long experiments in which the plasma albumin level remains at about 1 or 1 1/2% with relatively slight fluctuations up or down, while the plasma globulin curve shows striking variations depending upon whether or not plasma depletion is being carried out. The total protein curve parallels closely that for globulin. These results confirm the earlier work of Kerr, Hurwitz and Whipple. 2 It is easy to see, therefore, why the albumin/globulin ratio is usually reversed when there has been a long continued loss of plasma protein.