Abstract:

Objective   To study the changes of apoptosis-related genes including HSP70 and caspase-3 in rat brains after experimental intracerebral hemorrhage and the effects of the minimally hematoma aspiration on neuronal apoptosis. Methods   75 SD rats were randomly divided into 3 groups the sham operated group， the intracerebral hemorrhage group and the hematoma aspiration group. Then each group was divided by time(12h, 1d, 2d, 3d, and 7d).  2μL normal saline was injected into the caudate nucleus in the sham operated group，2μL -Ⅳ collagenase was injected to the caudate nucleus in the intracerebral hemorrhage group. The intracerebral hemorrhage models were treated by the hematoma aspiration method six hours after they were produced. In this way, the hematoma aspiration group was made. The rats were killed at each time point and then their brain tissues were isolated. Expressions of HSP70 and caspase-3 in the cerebral tissues surrounding cerebral hemorrhage at different times were detected by immunohistochemical techniques and were statistically analyzed.  Results   HSP70 and caspase-3 expressions in the intracerebral hemorrhage group were significantly higher than those in the hematoma aspiration group and the sham operated group (P<0.05). Genes expressions in the hematoma aspiration group were significantly higher than those in the sham group(P<0.05). HSP-70appeared at 12h, reached a maximum at 3d， and then gradually decreased. Caspase-3 appeared at 12h, reached a maximum at 3d， and was obviously reduced at 7d. Conclusions   High expression of caspase-3 showed that nerve cells apoptosis and damage reached a peak at the third day after intracerebral hemorrhage, then gradually decreased. High expression of HSP70 has an obviously protective effect on intracerebral hemorrhage tissues, and reduces expression of caspase-3. The intervention of minimal hematoma aspiration in the early stage of cerebral hemorrhage can reduce the apoptosis of nerve cells.

Key words: Heatshock proteins 70； Cerebral hemorrhage； Apoptosis； Minimally hematoma aspiration