The present study was conducted to examine the effect of bradykinin and bradykinin 2 receptor antagonist on survival time in rats with coronary artery ligation for 15 min and continuously. We also evaluated the heart rate and blood pressure responses in the presence and absence of bradykinin and its antagonist. Bradykinin treatment (4 microg and 8 microg/kg IV) significantly (p < 0.05) increased the survival time of rats compared with saline-treated rats with coronary artery ligation for 15 min and continuously. The heart rate and blood pressure responses were significantly (p < 0.001) altered in the presence of coronary artery ligation. Bradykinin antagonist treatment (4 microg/kg IV) abolished the effect of bradykinin and thus reduced the survival time of rats with coronary artery ligation. The mean value of survival time between saline-treated and bradykinin antagonist- plus bradykinin-treated rats did not differ significantly (p > 0.05).
Components of the kallikrein-kininogen-kinin are activated in response to noxious stimuli (chemical, physical or bacterial), which may lead to excessive release of kinins in the synovial joints that may produce inflammatory joint disease. The inflammatory changes observed in synovial tissue may be due to activation of B2 receptors. Kinins also stimulate the synthesis of other pro-inflammatory agents (PGs, LTs, histamine, EDRF, PGI2 and PAF) in the inflamed joint. B2 receptor antagonists may provide valuable agents as new analgesic drugs. Further, it is suggested that substances directed to reduce the activation of KKS may provide a pharmacological basis for the synthesis of novel anti-rheumatic or anti-inflammatory drugs.