Long-time course of protease-activated receptor-1 expression after intracerebral hemorrhage in rats.

Thrombin plays an important role in brain injuries associated with intracerebral hemorrhage (ICH). The protease-activated receptor (PAR)-1 is responsible for the vast majority of the thrombin's cellular activation functions. We tested the hypothesis that thrombin-induced brain damage after ICH, at least in part, is mediated by PAR-1. We report that there are significant differences between PAR-1 positive cell number and PAR-1 mRNA absorbance ratio between ICH model group (at 6h, 24h, 3 d, 7 d and 14 d) and normal group (P<0.05). These results suggest that the long-time course of PAR-1 expression may be partly involved in the mechanism of thrombin-induced brain damage after ICH.