去甲肾上腺素对肝星状细胞增殖和凋亡的影响

目的探讨交感神经递质去甲肾上腺素（NE）对HSC细胞株（CSFC）增殖和凋亡的影响。方法体外培养CFSC,分为以下6组：（1）空白对照组,为单纯CFSC培养;（2）交感兴奋（NE）组;（3）交感抑制（酚妥拉明＋普萘洛尔）组;（4）α肾上腺素受体（AR）阻滞（酚妥拉明）组;（5）β1AR阻滞（CGP20712A）组;（6）β2AR阻滞（ICI118551）组。MTT法测定细胞增殖;TUNEL法观察CFSC凋亡状况;流式细胞仪检测细胞凋亡率;倒置相差显微镜观察细胞形态学变化。结果MTT法显示,NE对CFSC具有明显的促增殖作用,加入α-AR、β1AR、β2AR阻滞剂后细胞增殖均受到明显抑制。NE作用于CFSC 24h,TUNEL法显示CFSC的凋亡率显著低于对照组（6.60%±3.05%与12.60%±4.76%,P〈0.05）;加入AR阻滞剂后CFSC凋亡率升高,其中α-AR和β2AR阻滞剂作用最显著。同时,流式细胞仪显示加入NE后CFSC凋亡率也显著降低（2.29%±0.22%与3.06%±0.57%,P〈0.05）;与TUNEL结果一致。NE对细胞形态没有明显影响。结论交感神经递质NE对体外活化的CFSC具有促增殖作用,并且可以抑制CFSC的凋亡,可能主要通过α受体和β2体起作用。

Effects of norepinephrine on hepatic stellate cell proliferation and apoptosis

OBJECTIVES: To investigate the effects of norepinephrine (NE) on the proliferation and apoptosis of hepatic stellate cells (HSCs). METHODS: Cultured HSCs were used in 6 groups: (1) a control group; (2) a NE group; (3) a phentolamine plus propranolol group; (4) a phentolamine (an alpha-AR antagonist) group; (5) a CGP20712A (a beta1-AR antagonist) group; and (6) a ICI118551(a beta2-AR antagonist) group. After NE and the antagonists of adrenoceptor subtypes were administered to the cultured HSCs, MTT assay was used to evaluate the cell proliferation at 24 h, 48 h, and 72 h. Terminal deoxyribonucleotidyltransferase-mediated dUTP nick end labelling (TUNEL) assay and flow cytometry were used to detect cell apoptosis. An inverted microscope was used to observe the morphological changes of HSCs. RESULTS: (1) MTT assay indicated that NE significantly induced HSCs proliferation in a time-dependent manner, which were reduced by antagonist of alpha-AR, beta1-AR and beta2-AR. (2) At 24 h after HSCs exposure to NE, apoptosis rates decreased significantly compared with that of the control group (6.60%+/-3.05% vs 12.60%+/-4.76%). In the antagonists of adrenoceptor subtypes groups, especially of a and beta2 adrenoceptor subtypes, the apoptosis was less. (3) Apoptosis rate of the NE group was significantly lower than that of the control group (2.29%+/-0.22% vs 3.06%+/-0.57%). In the antagonists of alpha and b2 adrenoceptor groups the apoptosis was less. (4) No obvious morphological changes of HSCs were found after administration of NE. CONCLUSIONS: Sympathetic neurotransmitter NE can induce proliferation and inhibit apoptosis of the cultured HSCs.