1981 年 101 巻 2 号 p. 161-168
We measured the blood oxygen tension (Po2) in the rat aorta in connection with cardiac lesions caused by the subcutaneous administration of sympathomimetic amines. The degree of cardiac lesions caused by l-isoproterenol, which acts predominantly on the β-receptor, or dl-norepinephrine, which acts predominantly on the α-receptor, was dose dependent, and these drugs decreased the Po2 in the same dose range. The decrease in Po2 due to dl-norfenefrine, which causes very little cardiac lesion and acts on the α-receptor, was not significant. Moreover, it is ascertained that cardiac lesions and a decrease in Po2 caused by l-isoproterenol could be prevented by pretreatment with propranolol and that cardiac lesions and a decrease in Po2 caused by dl-norepinephrine could be prevented by pretreatment with phentolamine.