Effects of human tissue kallikrein on cerebral vasospasm: experiment with rabbits

Abstract

To study the effects of human tissue kallikrein (HTK) on symptomatic cerebral vasospasm (CVS) after subarachnoid hemorrhage (SAH). Forty rabbits underwent occlusion of bilateral carotid. Two weeks later the 28 surviving rabbits were randomly divided into to 4 groups: shamed-operation group (n = 8) undergoing injection of normal saline into the cisterna magna on day 1 and day 3, SAH group (n = 6) undergoing injection of nonheparinized autologous arterial blood into the cisterna magna, HTK therapy group (n = 6) undergoing blood injection into the cisterna magna and then injection of HTK via ear marginal vein daily for 3 days, and nimodipine (ND) therapy group (n = 6) undergoing blood injection into the cisterna magna and then injection of ND via ear marginal vein. 3-dimension-CT angiography (3-D CTA) was used to measure the basilar artery diameter on D(0) and D(5). On D(6) the rabbits were killed with their basilar arteries taken out to undergo light microscopic examination. Blood could be seen in the basis cephalic of the 3 groups undergoing blood injection. 3-D CTA showed that arteriospasm was seen in the SAH and ND groups but not in the HTK group. Microscopy showed obvious pathological changes in basilar artery in the SAH and ND groups but not in the HTK group. HTK given early after SAH effectively alleviates the symptomatic cerebral vasospasm.