P物质对新生大鼠心肌细胞缺氧复氧损伤的影响

Effects of substance P on anoxia/reoxygenation injury to cardiomyocytes of neonatal rats

目的 探讨P物质对新生大鼠心肌细胞缺氧复氧损伤的影响.方法 新生SD大鼠,1～3日龄,处死后取心室肌组织,分离心肌细胞,接种于6孔培养板中,培养72 h.采用随机数字表法,将心肌细胞分为4组（n=3）：对照组（C组）常规培养6h;缺氧复氧组（A/R组）进行缺氧3h,复氧2 h;P物质组（SP组）给予终浓度为10-7mol/L的P物质孵育lh,行缺氧3h,复氧2h;P物质＋D-SP组（SP＋ D-SP组）给予终浓度为10-7mol/L的P物质和终浓度为10-mol/L的速激肽1型受体拮抗剂D-SP孵育lh,行缺氧3h,复氧2h.于复氧结束时,测定心肌细胞凋亡率和乳酸脱氢酶（LDH）活性.结果 与C组比较,A/R组、SP组和SP＋ D-SP组细胞凋亡率和LDH活性升高（P＜0.01）;与A/R组比较,SP组和SP＋ D-SP组细胞凋亡率和LDH活性降低（P＜0.01）;与SP组比较,SP＋ D-SP组细胞凋亡率和LDH活性升高（P＜0.01）.结论 P物质可减轻新生大鼠心肌细胞缺氧复氧损伤,其机制与激活速激肽1型受体有关.

Objective To investigate the effects of substance P on anoxia/reoxygenation （A/R） injury to cardiomyocytes of neonatal rats.Methods Cardiomyocytes of neonatal rats were isolated from Sprague-Dawley rats,aged 1-3 days,and were cultured in 6-well plates for 72 h.The cardiomyocytes were then assigned into 4 groups （n =3 each） using a random number table：control group （group C）,A/R group,substance P group （group SP） and substance P ＋ D-SP group （group SP ＋ D-SP）.The cells were cultured routinely for 6 h in group C and the cells were exposed to 99.9 % N2 in an incubator at 37 ℃ for 3 h followed by reoxygenation for 2 h in the other groups.The cells were incubated with substance P with the final concentration of 10-7 mol/L for 1 h before anoxia in group SP.The cells were incubated for 1 h with substance P with the final concentration of 10-7 mol/L and D-SP （a specific antagonist of neurokinin-1 receptor） with the final concentration of 10-6 mol/L before anoxia in group SP ＋ D-SP.The apoptosis rate and lactate dehydrogenase （LDH） activity were detected at the end of reoxygenation using TUNEL assay and LDH assay kit,respectively.Results Compared with C group,the apoptosis rate and LDH activity were significantly increased in A/R,SP and SP＋ D-SP groups.Compared with A/R group,the apoptosis rate and LDH activity were significantly decreased in SP and SP ＋ D-SP groups.Compared with SP group,the apoptosis rate and LDH activity were significantly increased in SP ＋ D-SP group.Conclusion Substance P can attenuate A/R injury to cardiomyocytes of neonatal rats,and activation of neurokinin 1 receptors is involved in the mechanism.