[Arginine vasopressin-induced nitric oxide content changes in cultured cardiac fibroblasts and its relation to...

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.