Effects of IL-1beta on inducible nitric oxide synthase-nitric oxide system activity in arginine vasopressin-induced rat cardiac fibroblasts / 中国应用生理学杂志

<p><b>AIM</b>To explore the effects of interleukin-1beta (IL-1beta) on inducible nitric oxide synthase (iNOS)-nitric oxide (NO) system activity in arginine vasopressin (AVP)-induced rat cardiac fibroblasts (CFs).</p><p><b>METHODS</b>CFs were isolated by trypsin digestion method. Nitric acid reductase method, spectrophotometry and reverse transcription-polymerase chain reaction (RT-PCR) were used to detect NO contents, NOS activity and iNOS mRNA expression.</p><p><b>RESULTS</b>AVP significantly increased iNOS mRNA expressions, NOS activity and NO contents (P < 0.05) in CFs. IL-1beta enhanced the effects of AVP on iNOS-NO system activity in a concentration-dependent manner, moreover the iNOS mRNA expressions, NOS activity and NO contents of AVP + 3 ng/ml, AVP + 5 ng/ml IL-1beta group were both significantly higher than those of AVP group (P < 0.05). But when IL-1beta concentration increased to 5 ng/ml, the iNOS mRNA expressions, NOS activity and NO contents did not increase accordingly, slightly decreased instead.</p><p><b>CONCLUSION</b>Within certain range of concentrations IL-1beta cooperates with AVP to increase iNOS-NO system activity in CFs.</p>

Arginine vasopressin-induced nitric oxide content changes in cultured cardiac fibroblasts and its relation to nuclear factor-kappaB / 生理学报

To investigate the changes in the nitric oxide (NO) contents, nitric oxide synthase (NOS) activity and inducible nitric oxide (iNOS) mRNA expression in arginine vasopressin (AVP)-induced cardiac fibroblasts (CFs) in vitro and its relation to nuclear factor-kappaB (NF-kappaB), CFs were isolated by trypsin digestion method. Nitric acid reductase method, spectrophotometry, reverse transcription-polymerase chain reaction (RT-PCR), immunofluorescence-interactive laser cytometer techniques and Western blotting were used respectively to detect NO contents, NOS activity, iNOS mRNA expression and the activation of NF-kappaB in CFs. AVP increased NO contents, NOS activity and iNOS mRNA expressions in a concentration-dependent manner; NF-kappaB was activated and mobilized from cytoplasm to nucleus in AVP-induced CFs; PDTC, one of the inhibitors of NF-kappaB, could inhibit aforementioned increments. It is suggested that the increases in NO contents, elevation of NOS activity and increment of iNOS mRNA expression may be mediated through NF-kappaB activation pathway in cultured CFs induced by AVP, and that NF-kappaB is involved in the occurrence and development of myocardial fibrosis.