Effects of cholecystokinin octapeptide on the response of rabbit pulomonary artery induced by LPS in vitro
GU Zhen-Yong, LING Yi-Ling, MENG Ai-Hong, CONG Bin, HUANG Shan-Sheng Department of Pathophysiology, Hebei Medical University, Shijiazhuang(050017)
AIM and METHODS:To elucidate the mechanism of cholecystokinin (CCK) for attenuation of pulmonary hypertension in the early stage of endotoxin shock in vitro , effects of CCK-8, an important functional fragment of endogenous CCK, on the responses of rabbit pulmonary artery induced by lipopolysaccharides (LPS) in vitro were observed with isolated artery ring technique. RESULTS:The exposure of pulmonary artery to LPS (4μg/mL, 2h) 1ed to enhancement of its contractile response to α-adrenoceptor agonist phenylephrine (PE) but reduction of its relaxation response to acetylcholine, an endothelium-dependent vasodilator, both of which were reversed by the concomitant exposure to CCK-8(0.1 μg/mL and 0.5 μg/mL), whereas incubation of pulmonary artery with CCK-8 (0.5 μg/mL) had no effect on the responses. CONCLUSION:CCK can protect pulmonary artery endothelia against detrimental effects by LPS, which may be one of mechanisms underlying anti-pulmonary hypertension of CCK.