【摘要】 盐酸甲基麻黄碱80mg·kg^-1和40mg·kg^-1对氨水引咳的小鼠咳嗽有明显抑制作用;对氯化乙酰胆碱和磷酸组胺所引起的豚鼠哮喘有平喘作用;对正常豚鼠和组胺处理过的气管条均有松弛作用,其PD₂（完全激动剂或不完全激动剂引起最大反应50％所需的克分子浓度负对数）和PA-2（使激动剂的量-效曲线向高剂量方向移动2倍所需的竞争性拮抗剂的克分子浓度负对数）分别为6.07和7.05。更多还原

【Abstract】 Methylephedrine hydrochloried. when administered at the dose of 80 or 40mg · kg-1, could significantly inhibit the ammonia induced cough in mice , and it also showed an antiasthmatic activity on the experimental asthma of guinea pig induced by acetylcholine or histamine. The drug made the isolated guinea pig tracheal strip relax under normal or histamine - treated conditions. The PD2(the negative logarithm of the concentration of the agonist which produced a 50% contractile response of maximun)and PA2(the negative logarithm of the concentration of the antagonist which produced a right shift of the cumulative dose response curve of histamine to a dose level two-fold as initial one of the drug were 6. 07 and 7. 05 respectively.更多还原