Experimental study on the expression of HIF-1α and its relationship to apoptosis in tissues around cerebral bleeding loci

Abstract

The expression of hypoxia inducible factor-1 alpha (HIF-1α) and its relationship to apoptosis in tissues around cerebral bleeding loci was studied. The expression of HIF-1α and apoptosis in 37 samples of tissues around cerebral bleeding loci and 9 samples of normal cerebral tissues was assessed by immunohistochemical straining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling methods. In 37 tissue samples around cerebral bleeding loci, the positive rate of the HIF 1α expression was 40.6%. Especially in the patients with amount of bleeding >60 ml, the positive rate (88.9%) of the HIF-1α expression was significantly higher than those with the amount of blceding ranging from 30, 45 ml or 45, 60 ml (P<0.05). The expression of HIF-1α was increased as the amount of bleeding and operative time increased (P<0.05). There existed a positive correlation between HIF-1α labeling index and apoptosis index (n=12,r=0.56,P<0.01). These results suggested that the expression of HIF-1α was closely related with the time of hemorrhage and the amount of bleeding, and could induce the apoptosis of neurons.

Keywords

cerebral hemorrhage / hypoxia inducible factor-1 alpha / apoptosis

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