Changes in plasma kallikrein and PGF2 alfa concentrations during circulatory shock. Studies with superior mesenteric artery occlusion in anesthetized dogs.

Among the mediators for development of endotoxic shock, plasma kallikrein and prostanoids have been suggested to play an important role. The role of kallikrein and PGF2 alfa in circulatory shock of intestinal origin was investigated in anesthetized dogs by measuring inactive and active kallikreins and PGF2 alpha in superior mesenteric vein, right ventricle and aorta during shock induced by occlusion of the superior mesenteric artery. After removal of the clamp in dogs subjected to occlusion for 1 hour, the mean arterial blood pressure fell rapidly within 5 min and gradually increased over the next 60 min, with return to the control values. The plasma concentrations of PGF2 alfa in superior mesenteric vein, right ventricle and aorta increased three- to fivefold within 5 min of reperfusion. Thereafter the PGF2 alfa levels fell, so that at 60 min after declamping they did not significantly differ from the control values. No significant changes were observed in the levels of inactive and active kallikreins. The results suggest that PGF2 alfa released by intestinal tissues may contribute to the development of shock caused by intestinal ischemia.