Detection of reticuloendothelial-depressing substance in shock

¹ Research Division, St. Vincent Charity Hospital, Cleveland, Ohio

In an effort to find an in vitro method to detect the presence of reticuloendothelial-depressing substance (RDS), two tests were devised which measured phagocytic activity. One used carbon particles to measure phagocytosis and the other P³²-labeled Escherichia coli. Neither method demonstrated an in vitro difference in granulopectic activity between dog plasmas from sham-operated and hemorrhagic-shock or superior mesenteric artery-occluded (SMAO) animals. An in vivo method was used in which the reticuloendothelial activity of the rat was measured in terms of the rate of clearance of injected carbon particles. Occlusion of the superior mesenteric artery of the rat led to the production of RDS. The RDS could be transferred to and demonstrated in a normal rat by means of SMAO rat whole blood, plasma, and dialysate of plasma, but not in RBC or plasma which had been dialyzed. Sham-operated animals were used as controls.

Note:
With the Technical Assistance of F. A. Blattberg and I. Strong

Key Words: hemorrhagic shock • superior mesenteric artery occlusion • phagocytic activity in vivo and in vitro • reticuloendothelial system • carbon clearance