中文摘要：

按常规饲养条件饲养AA雄性肉鸡120羽，30日龄时随机分为试验组（T组）和对照组（C组）。T组肉鸡静脉注射L-AG（40mg／kg），C组肉鸡静脉注射生理盐水。分别在注射L-AG和生理盐水1、2、4h后测定平均肺动脉压（mPAP）、诱导型一氧化氮合酶（iNOS）活性、原生型一氧化氮舍酶（cNOS）活性、一氧化氮（NO）含量、红细胞压积（PCV）、电解质浓度、pH、超氧化物歧化酶（SOD）活性、过氧化氢酶（CAT）活性和丙二醛（MDA）含量。结果显示：（1）试验组mPAP、NO含量和iNOS活性均显著或极显著低于对照组（P〈0．05或P〈0．01）；（2）PCV和Ca^2＋在给药后2h和4h与对照组差异显著（P〈0．05）；（3）K^＋浓度在给药1h和2h后显著或极显著低于时照组（P〈0．05或P〈0．01）。结果表明，L-AG通过抑制iNOS活性，引起肉鸡肺动脉压的升高，从而推测iNOS具有调节肉鸡体内mPAP的作用并与肉鸡肺动脉高压综合征发生有着密切的联系。

英文摘要：

This experiment was conducted to evaluate the effect of L-AG on the pulmonary hypertension and other concerned index in broilers. One hundred and twenty 1-day-old commercial male broilers were raised according to AA feeding condition until 30 days and then the broilers were divided into a experimental （T） group and a control （C） group. Group T and Group C were given L-AG at dose of 40 mg/kg and physiological saline through intravenous injection, respecitively. The mPAP, inducible oxide synthase （iNOS） activity, constitutive oxide synthase （cNOS） activity, nitric oxide （NO） level, PCV, electrolyte level, pH, s uperoxide dismutase （SOD）, catalase （CAT）, malondialdehyde （MDA） were measured at 1,2,4 hours after administration of L-AG and physiological saline. Results were as follow： （1）From 1 to 4 hours,the mPAP,the NO level and the iNOS activities of group T were significant higher than that of group C（P〈0.05 or P〈0.01 ） ; （2）Compared with group C, PCV and Ca^2＋ of group T were significant difference within 2-4 hours after administrating the dose （P〈0. 05）; （3）Compared with group C,K^＋ concentration was significant lower within 1-2 hours after administering the dose（P〈0. 05 or P〈0.01 ）. It is suggested that the L-AG can induce pH by inhibiting the serum iNOS activity,therefore ,iNOS has an effect on adjusting the mPAP of broilers and my play an important role on the mechanism of PHS.