降钙素基因相关肽对重症中暑大鼠脑细胞凋亡的作用研究

Study on the effect of calcitonin gene-related peptide on brain cells apoptosis in rats with heatstroke

目的探讨降钙素基因相关肽(CGRP)对重症中暑大鼠脑细胞凋亡的影响。方法应用可调节人工气候舱建立大鼠重症中暑模型。将20只大鼠分为对照组、热打击组(HS组)、热打击+注射CGRP组(HS+CGRP组)、热打击+注射CGRP8-37组(HS+CGRP8-37组),每组5只。在热打击后HS+CGRP组大鼠均立即经颈动脉注射CGRP,HS+CGRP8-37组大鼠均立即经颈动脉注射CGRP8-37。所有大鼠于造模2 h后取脑组织检测细胞凋亡、半胱天冬酶-3(Caspase-3)、B淋巴细胞瘤-2基因蛋白(Bcl-2)。结果与HS组大鼠比较,HS+CGRP组大鼠的脑细胞凋亡水平明显减少,而HS+CGRP8-37组大鼠则显著增加,差异均有统计学意义(P<0.05),而与对照组比较,HS组大鼠脑细胞凋亡水平有显著升高,差异有统计学意义(P<0.05);与HS组大鼠比较,HS+CGRP组大鼠的脑组织活化Caspase-3蛋白水平明显减少,而HS+CGRP8-37组则显著增加,差异均有统计学意义(P<0.05);HS组大鼠的Bcl-2蛋白表达水平较对照组明显下降,注射CGRP后,Bcl-2蛋白水平较HS组显著增加,差异均有统计学意义(P<0.05);注射CGRP8-37后,Bcl-2显著下降,与对照组比较差异有统计学意义(P<0.05)。结论CGRP对重症中暑大鼠脑细胞凋亡有抑制作用。

Objective To investigate the effect of calcitonin gene-related peptide(CGRP)on brain cells apopto-sis in rats with heatstroke.Methods The model of heatstroke in rats was established by using an adjustable artificial cli-mate chamber.Twenty rats were divided into control group,heat stroke group(HS group),heat stroke and CGRP injec-tion group(HS+CGRP group),heat stroke and CGRP8-37 injection group(HS+CGRP8-37 group),with 5 rats in each group.After the heat shock,rats in the HS+CGRP group were immediately injected with CGRP through the carotid ar-tery,and rats in the HS+CGRP8-37 group were immediately injected with CGRP8-37 through the carotid artery.The brain tissues of all rats were taken 2 h after modeling to detect the level of cell apoptosis,Caspase-3,and B-cell lympho-ma 2(Bcl-2)protein.Results Compared with the HS group,the brain cell apoptosis level of the HS+CGRP group was significantly decreased,while that of HS+CGRP8-37 group was significantly increased(P<0.05);compared with the control group,the brain cell apoptosis level of the HS group was significantly increased(P<0.05).Compared with the HS group,the expression of activated Caspase-3 protein of the HS+CGRP group was significantly decreased(P<0.05),while that of the HS+CGRP8-37 group was significantly increased(P<0.05).The expression level of Bcl-2 protein in the HS group was significantly lower than that in the control group;however,after injection of CGRP,the Bcl-2 expres-sion level increased significantly compared with the HS group(P<0.05).After injection of CGRP8-37,the Bcl-2 expres-sion level decreased significantly compared with the control group(P<0.05).Conclusion CGRP can inhibit the apopto-sis of brain cells in rats with heatstroke.