鼠心肌成纤维细胞NOS活性的变化和AVP对NO合成的影响

Changes of NOS activity in rat cardiac fibroblasts and the influence of arginine vasopressin on NO contents

目的 探讨在基础状态和精氨酸升压素 (AVP)干预下 ,心肌成纤维细胞 (CFs)一氧化氮合酶 -一氧化氮 (NOS-NO)系统活性的变化 .方法 胰酶消化法分离、培养新生 SD大鼠 CFs,采用硝酸还原酶法和分光光度法分别测定基础状态和 AVP干预下 CFs的 NOS活性和 NO含量 .结果 1基础状态下 CFs的 36 h组 NO含量 (4 2± 5 ) μm ol· L- 1 和 NOS活性 (6 17± 83)μkat· L- 1 ,显著高于 6 h组 (14± 3)μmol·L- 1 ,(16 7± 6 7)μkat· L- 1 . 2 AVP干预下 36 h组 NO含量(6 2± 1) μm ol· L- 1和 NOS活性 (115 0± 10 0 ) μkat· L- 1也显著高于 6 h组 (34± 4) μmol· L- 1 ,(6 0 0± 33) μkat· L- 1 ,且AVP干预组的 NO含量和 NOS活性均高于同时间点基础状态组(P<0 .0 5 ) . 3CFs的 NO含量和 NOS活性随 AVP浓度的增高而增加 ,其中 10 - 6mol· L- 1 AVP组 (6 3± 6 ) μmol· L- 1 ,(110 0± 5 0 )μkat· L- 1 和 10 - 7mol· L- 1 AVP组 (6 9± 6 )μmol· L- 1 ,(12 0 0± 5 0 )μkat· L- 1 都显著高于对照组 (2 9± 5 )μmol· L- 1 ,(4 5 0± 83) μkat· L- 1 ,10 - 9mol· L- 1 AVP组(32± 2 )μmol· L- 1 ,(5 0 0± 133)μkat· L- 1 和 10 - 8mol·L- 1 AVP组 (37± 2 ) μmol· L- 1 ,(6 0 0?

AIM To investigate the changes of nitric oxide synthase nitric oxide (NOS NO) system activity in rat cardiac fibroblasts (CFs) with and without arginine vasopressin (AVP) treatment. METHODS CFs were isolated by trypsin digestion method. Nitric acid reductase method and spectrophotometry were used to detect the NO contents and NOS activity in AVP group (with AVP treatment) and control group without AVP treatment respectively. RESULTS ① NO contents (42±5) μmol·L -1 and NOS activity at 36 h (617±83) μkat·L -1 were higher than those at 6 h (14±3) μmol·L -1 , (167±67) μkat·L -1 in control group. ② NO contents (62±2) μmol·L -1 and NOS activity at 36 h (1150±100) μkat·L -1 were also higher than those at 6 h (34±4) μmol·L -1 , (600±33) μkat·L -1 in AVP group. NO contents and NOS activity of AVP group were both higher than those of control group ( P <0.05). ③ NO contents and NOS activity increased in a dose dependent manner in AVP group. NO contents and NOS activity under 10 -6 mol·L -1 AVP treatment (63±6) μmol·L -1 , (1100±50) μkat·L -1 and under 10 -7 mol·L -1 AVP treatment (69±6) μmol·L -1 , (1200±50) μkat·L -1 were both higher than those of control group (29±5) μmol·L -1 , (450±83) μkat·L -1 , those under 10 -9 mol·L -1 AVP treatment (32±2) μmol·L -1 , (500±133) μkat·L -1 and those under 10 -8 AVP treatment (37±2) μmol· L -1 , (600±67) μkat·L -1 ( P <0.05). ④ NO contents increased with the enhancement of NOS activity with different concentrations of AVP, and there was significant positive correlation between them ( r =0.964, P <0.01). CONCLUSION AVP increases NOS NO system activity in neonatal rat CFs. The enhancement of NOS NO system activity could inhibit myocardial fibrosis induced by AVP.