丙泊酚联合利血平对再灌注损伤PC12细胞保护作用的研究

目的 观察丙泊酚与利血平单用或合用对缺血/缺氧及再灌注致中枢神经元细胞损伤的保护作用及其可能机制.方法 用大鼠肾上腺嗜铬细胞瘤克隆化细胞株(PC12细胞)建立缺血/缺氧及再灌注损伤的细胞模型.实验分为缺血/缺氧及再灌注损伤(IR)组、丙泊酚(P)组、利血平(R)组、丙泊酚与利血平合用(PR)组.通过测定乳酸脱氢酶(LDH)含量及应用噻唑蓝(MTT)比色法测定存活细胞在波长570 nm处的吸光度(A)值用以判断细胞损伤程度,并观察两药单独或合用对损伤PC12细胞内游离钙离子浓度(Ca2+]I)的影响.结果 与IR组比较,丙泊酚和利血平单用或联用组均可使LDH释放量明显降低,A值升高(P<0.05或P<0.01).合用利血平(40μmol/L)后,不同浓度丙泊酚(12.4、37.3和112.0μmol/L)组LDH释放量进一步降低,A值则增高(P均<0.05).12.4μmol/L和37.3μmol/L丙泊酚以及40μmol/L利血平均可减轻由于缺血/缺氧及再灌注损伤引起的细胞内钙超载(279.66±18.00)nmol/L比(219.41±12.53)nmol/L,(279.66±18.00)nmol/L比(210.50±11.03)nmol/L,(279.66±18.00)nmol/L比(254.82±10.45)nmol/L,P<0.05或P<0.01];12.4/μmol/L和37.3μmol/L丙泊酚分别与40μmol/L利血平合用时,Ca2+]I进一步降至(1 91.19±10.36)nmol/L和(183.82±9.83)nmol/L,与相同浓度丙泊酚组比较差异均有统计学意义(P均<0.05).结论 丙泊酚和利血平均对缺血/缺氧及再灌注损伤PC12细胞产生一定的保护作用,合用时保护作用更明显;其保护作用可能与减轻细胞内钙超载有关.

Protective effects of propofol combined with reserpine on cultured PC12 cells impaired by ischemia and reperfusion

OBJECTIVE: To evaluate the protective action of propofol and reserpine, as well as a combination of the two drugs on cultured pheochromocytoma cells (PC12 cells) impaired by mimic ischemia reperfusion (IR), and its possible mechanisms. METHODS: PC12 cells were subjected to IR to reproduce the experimental model. They were divided into IR group, propofol (P) group, reserpine (R) group, and aspropofol/reserpine combined treatment (PR) group. The scale of cell impairment in each group was assessed by the content of lactate dehydrogenase (LDH) and by the absorption (A) at 570 nm with the methyl thiazolyl tetrazolium (MTT) assay. The change in Ca(2+)]i was detected by Fura-2/AM fluorescence assay after the treatment of propofol, reserpine, or both. RESULTS: Compared with IR group, the release of LDH was decreased and the A values increased in P, R and PR groups (P<0.05 or P<0.01). When combined with reserpine (40 mumol/L), different concentrations of propofol (12.4, 37.3 and 112.0 mumol/L) rendered the cells to release less LDH, with an increase in A value (all P<0.05). Both propofol (12.4 mumol/L and 37.3 mumol/L) and reserpine (40 mumol/L) could lessen the overload of intra-cellular calcium after IR (279.66+/-18.00) nmol/L vs. (219.41+/-12.53) nmol/L, (279.66+/-18.00) nmol/L vs. (210.50+/-11.03) nmol/L, (279.66+/-18.00) nmol/L vs. (254.82+/-10.45) nmol/L,P<0.05 or P<0.01]. Ca(2+)]i could be further lowered when the cells were treated with propofol and reserpine in combination (191.19+/-10.36) nmol/L and (183.82+/-9.83) nmol/L, both P<0.05]. CONCLUSION: Both propofol and reserpine can protect cells from IR injury, and attenuate Ca(2+)]i overload induced by IR. The attenuation of Ca(2+)]i overload in impaired cells may be one of the mechanisms for their protective actions.