This Study was designed to determine whether elevated or decreased blood nitric oxide (NOx) values following injections of L-arginine and N(infinity)-nitroarginine methylester (L-NAME) are positively correlated with the erythrocyte sedimentation rate (ESR) in healthy rabbits. The study involved 21 New Zealand rabbits of both sexes, aged between 10 and 15 months old. They were divided into 3 equal groups. The control group received 1 ml isotonic saline per rabbit, and Groups I and II received 100 mg/kg L-NAME and 250 mg/kg L-arginine intraperitoneally, respectively. After two hours blood samples were obtained and ESR (30, 60, and 120 minutes) and NOx were estimated. There were no significant differences between the ESR values at all times; however significant correlation between the NOx and ESR existed in Group II at 2 hours after injection. In conclusion, there was a positive correlation between high blood NOx and ESR values, but detailed studies are needed to disclose this correlation.