【摘要】 研究了Ｌ－精氨酸（Ｌ－Ａｒｇ）对急慢性缺氧大鼠肺循环和脑血流的影响。一次注射Ｌ－Ａｒｇ４００ｍｇ·ｋｇ￣（－１）对急性缺氧性肺血管收缩反应（ＨＰＶ）无影响，而８００ｍｇ·ｋｇ￣（－１）有明显抑制作用；两种剂量的Ｌ－Ａｒｇ对缺氧性脑血流的变化均无显著影响。Ｌ－Ａｒｇ（３００ｍｇ·ｋｇ￣（－１）·ｄ￣（－１））能缓解慢性缺氧性肺动脉高压、肺血管阻力增高和右心肥厚，并抑制ＨＰＶ，但对脑血流无显著影响。ＮＯ合成酶抑制剂Ｌ－精氨酸甲酯可拮抗Ｌ－Ａｒｇ的作用，提示Ｌ－Ａｒｇ的作用可能与增加ＮＯ合成有关。更多还原

【Abstract】 he effects of L-arginine(L-Arg)on pulmonarycirculation and cerebral blood flow in acute andchronic hypoxic rats and their mechanism were stu-died.The results showed that bolus injection of L-Arg400mg· kg￣(-1) did not inhibit acute hypoxic pulmonaryvasoconstriction(HPV),while 800mg· kg￣(-1) could in-hibit HPV. Neither of these two doses of L-Arg wasfound to have any influence on the change in cerebralblood flow during acute hypoxia. Long-term admini-stration of L-Arg (300mg· kg￣(-1)/ d)could attenuatechronic hypoxic pulmonary hypertension,the increasein pulmonary vascular resistance and right ventricularhypertrophy,and the HPV as well.It did not influencethe cerebral blood flow. Since the inhibitor of NOsynthetase,NG-nitro-L-arginine methyl ester,couldantagonize the effect of L-Arg, it is suggested that anincrease in the synthesis of NO might contribute to theeffect of L-Arg.更多还原