一氧化氮对心肌细胞缺氧复氧时脂质过氧化损伤的保护作用

Protective effect of nitric oxide on lipid peroxidation in anoxia/ reoxygenation injury of cardiac myocytes

目的:研究一氧化氮对培养鼠心肌细胞缺氧复氧所致脂质过氧化损伤的保护作用,探讨心肌缺血修复机制。 方法:采用细胞缺氧复氧损伤模型,培养细胞随机分为4组:A组正常对照组(培养3 h);B组单纯缺氧/复氧(A/R缺氧2 h复氧1 h);C组缺氧预处理组(缺氧20 min后复氧20 min,然后缺氧复氧);D组一氧化氮预处理组[加入S-亚硝基-已酰青酶胺(s-nitroso-n-acetyl-penicillamine,SNAP)使其终浓度为l mmol/L,预处理40 min后A/R。与复氧后测定培养液中肌酸激酶(creatine kinase,CK)、乳酸脱氢酶(lacfic dehydrogenase,LDH)活性变化及细胞内丙二醛含量和细胞存活率。结果:与正常组比,单纯缺氧/复氧组CK[(941.35±152.53)nkat/L]、 LDH[(7 416.48+984.20)nkat/L]、丙二醛[(1.35±0.26)μmol/g],水平显著井高(P<0.01),细胞存活率(54.68±6.00)％显著降低(P<0.01)。1 mmol/L SNAP预处理组[细胞存活率为(74.55±4.11),CK为(582.45±140.86)nkat/L,LDH为(5 766.15±941.69)nkat/L,丙二醛为(0.89±0.16)μmol/g]和缺氧预处理组[细胞存活率为(74.69±6.14)。CK为(547.94±125.52)nkat/L,LDH为(5 882.34±844.67)nkat/L,丙二醛为(0.85±0.12)μmol/g]上述变化明显减轻(P<0.01)。 结论:一氧化氮可抑制脂质过氧化反应,减轻自由基对心肌?

AIM: To study the effects of nitric oxide (NO) in protecting cardiac myocytes from lipid peroxidation injury caused by anoxia/reoxygenation in neonatal rat METHODS: An anoxia/reoxygenation model of myocardial cells of neonatal SD rat was established. The cells were randomly divided into four groups: normal control group (group A, without any pretrearment cultured for 3 h), anoxia/reoxygenation group (group B, 2 h anoxia followed by 1 h reoxy-genation), anoxia preconditioning group(group C, reoxygenation of 20 min anoxia followed by 20 min reoxygenation, then anoxia/reoxygenation) and NO preconditioning group [group D, adding s-nitroso-n-acetyl-penicillamine (SNAP) into culture medium with the final concentration of 1 mmol/L for 40 min preconditioning and then A/R]. The activity of creatine kinase (CK), lactic dehydrogenase(LDH), the contents of cellular malondiadehyde (MDA), the rate of cell viability were evaluated after reoxygenation. RESULTS: Compared with the normal control group, levels of CK [(941. 35 ±152. 53) nkat/L], LDH[(7 416. 48 ±984. 20) nkat/L] and MDA[(1. 35 ±0. 26)μmol/g] increased significantly(P <0.01), and cell viability(54. 68 ± 6. 00)% decreased significantly(P < 0. 01) in group B. These changes in group D[cell viability(74. 55 ±4. 11), CK(582. 45 ± 140. 86)nkat/L, LDH (5 766. 15 ±941. 69)nkat/L, MDA (0. 89 ±0. 16) (μmol/g] and group C[cell viability(74. 69 ±6. 14), CK(547. 94 ± 125. 52) nkat/L, LDH(5 882. 34 ± 844. 67) nkat/L, MDA(0. 85 ±0. 12) μmol/g] were relieved obviously( P < 0. 01).CONCLUSION: NO has the protective effect as anoxia preconditioning on myocardial cells by inhibiting lipid peroxidation and attenuating the oxygen free radicals mediating damage to the myocardium.