摘要
目的验证缺氧复氧诱发的新生大鼠心肌细胞蛋白质酪氨酸磷酸酶-1B（PTP-1B）的表达和活性的增加是否由一氧化氮（NO）介导。方法分离的新生大鼠心肌细胞，随机分为正常组、缺氧复氧组、非特异性一氧化氮合成酶抑制剂L-NAME组（L-NAME组）、缺氧复氧和L-NAME组（L-NA＋H／R组）。心肌细胞中PTP．1B的活性和表达分别由405nm的光谱测量仪和Western blot法检测。同时分析心肌细胞培养基中的NO的浓度和乳酸脱氢酶活性。结果与正常组比较，缺氧复氧组中心肌细胞PTP-1B的活性和表达较高，（L．NA＋H／R）组PTP-1B的活性和表达不高。与缺氧复氧组比较，（L-NA＋H／R）组NO和乳酸脱氢酶浓度显著低。缺氧复氧组和L-NA＋H／R组中的NO含量分别是正常组（100％）的（368±13）％和（61±7）％（P〈0．005）；缺氧复氧组、L-NAME＋H／R组中的乳酸脱氢酶的活性值分别为41．2±6．7和23．6±4．8（P〈0．05）。结论L-NAME预处理阻止了缺氧复氧诱发的大鼠心肌细胞中PTP-1B活性和表达的增加，提示缺氧复氧期间PTP-1B的变化是由NO介导的。
Objective To explore ff the hypoxia/reoxygenation-induced increased activity and expression of PTP-1B in neonatal rat eardiomyoeytes are mediated by nitric oxide （NO）. Methods Neonatal rat eardlomyoeytes were isolated and randomly divided into 4 groups ： normal group （ N group） ; hypoxia/ reoxygenation group （H/R group）; N^w-nitro-l-arginine methylester treated group （L-NAME group ）; hypoxia/reoxygenation plus L-NAME group （L-NA ＋ H/R group）. PTP-1B activity in eardiomyoeytes was determined speetrophotometrieally at 405 nm, PTP-1B expression in eardiomyoeytes was detected by Western blot. NO and LDH concentrations in cell medium were also assayed. Results PTP-1B activity and expression in eardiomyoeytes was significantly higher in the H/R group as compared to the N group and this increase could be blocked by eotreatment with L-NAME. As compared to H/R group, nitric oxide and LDH concentrations in cell medium were significantly decreased in the L-NA ＋ H/R group （NO concentration： H/R group, 368% ± 13% and L-NA ＋ H/R group, 61% ± 7%, P 〈0.005; LDH concentration： H/R group, 41.2 ± 6.7 and L-NA ＋ H/R group, 23.6 ± 4. 8, P 〈 0. 05）. Conclusions This study showed that pretreatment with L-NAME, a non-selective inhibitor of NOS, prevented the hypoxia/reoxygenation-indueed increase in PTP-1B activity and expression in eardiomyoeytes, suggesting PTP-1B activation during hypoxia/ reoxyogenation was mediated by nitric oxide.
出处
《中华心血管病杂志》
CAS
CSCD
北大核心
2008年第8期735-737,共3页
Chinese Journal of Cardiology
关键词
心肌
细胞凋亡
一氧化氮
蛋白质酪氨酸磷酸酶
缺氧复氧
Myoeardium
Apoptosis
Nitric oxide
Protein-tyrosine-phosphatase
Hypoxia, reoxygenation
