EFFECTS OF IL-1β ON INDUCIBLE NITRIC OXIDE SYNTHASE-NITRIC OXIDE SYSTEM ACTIVITY IN ARGININE

Aim: To explore the effects of interleukin-1β(IL-1β) on inducible nitric oxide synthase(iNOS)-nitric oxide(NO) system acti-vity in arginine vasopressin(AVP)-induced rat cardiac fibroblasts(CFs).Methods: 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.Results: AVP significantly increased iNOS mRNA expressions,NOS acti-vity and NO contents(P0.05) in CFs.IL-1β 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+5ng/ml IL-1β group were both significantly higher than those of AVP group(P0.05).But when IL-1β concentration increased to 5ng/ml,the iNOS mRNA expressions,NOS activity andNO contents did not increase accordingly,slightly decreased instead.Conclusion: Within certain range of concentrations IL-1β cooperates with AVP to increase iNOS-NO system activity in CFs.