Effect of hemorrhage on cell apoptosis in hippocampal CA1 region of rats under controlled hypotension / 中南大学学报(医学版)

ABSTRACT

Objective To explore the effect of hemorrhage on cell apoptosis in the hippocampal CA1 region of rats under controlled hypotension (CH).Methods A total of 36 Sprague Dawley rats were randomly divided into 2 groups Group C (with no CH) and Group H (with CH).According to different ratios of blood loss to total blood volume, Group C and Group H were redivided into 6 subgroups (6 in each group)C_1,H_1(10%);C_2,H_2(20%);C_3,H_3 (30%). Induced by so-dium nitroprusside and esmolol, the mean aterial pressure in Group H was decreased to 50～55 mmHg and kept for 10 minutes, and then blood loss was started, keeping the pump speed. Without CH, the same style of hemorrhage was performed in Group C. The aterial pressure was increased 60 minutes later after the hemorrhage.Expression of bcl-2 and caspase-3 protein was detected by immunohistochemical method, and apoptosis cells were detected by TUNEL staining. Results The average optical density of bcl-2 and caspase-3 was higher in Group H_3 than that in Group C_3(P＜0.05). There were more apoptosis cells examined by TUNEL in Group H_3 than in Group C_3(P＜0.05).Conclusion Thirty percent blood loss under controlled hypotension can induce cell apoptosis in hippocampal CA1 region in rats.