Experimental study on the PAR-1 expression around hemotoma following intracerebral hemorrhage in rats.

In order to explore the PAR-1 mRNA and protein expression around hemotoma following intracerebral hemorrhage and the relation between the PAR-1 expression and thrombin, collagenase VII was stereotaxically injected into right caudate nucleus in rats. The PAR-1 mRNA expression was detected by RT-PCR method and the PAR-1 protein expression by immunohistochemical method respectively. It was found that the PAR-1 mRNA and protein expression around hemotoma was increased at 6 h after intracerebral hemorrhage (P<0.05), peaked at 2 days (P<0.01), and then declined. The change pattern of the PAR-1 mRNA and protein expression was similar to that of intracerebral hemorrhage after thrombin intracerebral injection. The PAR-1 mRNA and protein expression in hirudin group showed no significant difference with control group. These results indicated that the PAR-1 mRNA and protein expression were markedly increased after intracerebral hemorrhage, which may be closely related to thrombin. Upregulation of the PAR-1 expression may involve in neurotoxic injury induced by thrombin.