The Evaluation of Increased Vascular Permeability in the Skin of Guinea‐pigs

This is the authors' abstract. We don't add key points for this paper.

Summary The increases in vascular permeability induced by the intracutaneous injection of histamine, compound 48/80, polymyxin B, bradykinin, globulin permeability factor and kallikrein were compared in the skin of the dorsal trunk of guinea‐pigs with Evans blue circulating in their blood. With respect to log dose injected, the response in treated sites was evaluated in three ways: (1) diameter of the blue lesions on the upper and (2) under surfaces of the skin: (3) the amount of dye that exuded into the skin. Based on the upper surface readings, bradykinin had outstanding activity, followed by globulin permeability factor, histamine, compound 48/80, polymyxin B and kallikrein in that order. The relative potency was 11,090, 143, 110, 24, 6 and 1 respectively. The upper surface readings yielded parallel response‐lines. On the under surface, the slopes of the response‐lines for bradykinin and 48/80 differed from those of the other four substances, and hence potency was calculated at an arbitrary level. Based on the under‐surface readings, bradykinin still had outstanding activity (relative potency = 3,514), but the descending order now was histnmine (166), 48/80 (29), globulin factor (28), polymyxin B (7) and kallikrein (1). The response‐lines recording the amounts of exuded dye were reasonably parallel, and the corresponding relative potency of the test substances closely agreed with the results from the under‐surface readings. In general, the differences between the upper and under surface readings corresponded to the distribution of dye in the various layers of the skin.