척출 냉혈동물 심방의 Alpha-Adrenoceptors에 관한 연구(I) 개구리 심방의 clonidine, oxymetazoline 및 phenylephrine에 대한 반응

• 영문명: Study on Alpha-Adrenoceptors of the Isolated Atrium in Cold Blood Animals(I) Experiments with clonidine, oxymetazoline and phenylephrine in frog atria
• 발행기관: 대한약학회
• 저자명: 최수형(Soo Hyung Choi) 박행순(Haeng Soon Park) 신동호(Dong Ho Shin)
• 간행물 정보: 『약학회지』제32권 제2호 (1988년), 129~136쪽, 전체 8쪽
• 주제분류: 의약학 > 기타의약학
• 파일형태: PDF
• 발행일자: 1988.04.29

영문 초록

Effects of the selective alpha-adrenoceptor agonists, clonidine, oxymetazoline and phenylephrine, on heart rate and contractile force were investigated in the isolated frog atria and it was attempted to examine the influence of adrenoceptor antagonist upon those. Clonidine produced dose-dependent negative chronotropic and positive inotropic effects. The negative chronotropic effect was significantly attenuated in the presence of prazosin and yohimbine but not propranolol. The positive inotropic effect was significantly attenuated by prazosin, yohimbine and propranolol. Oxymetazoline produced dose-dependent negative chronotropic and inotropic effects. The negative chronotropic effect was significantly attenuated in the presence of prazosin, which was partially augmented by yohimbine but was not affected by propranolol. The negative inotropic effect was not affected by propranolol but it was partially augmented by yohimbine and was partially attenuated by prazosin. Phenylephrine produced dose-dependent positive chronotropic and inotropic effects. The positive chronotropic and inotropic effect were significantly attenuated in the presence of propranolol but were not affected by prazosin and yohimbine. These results suggest that the negative chronotropic effect by clonidine and oxymetazoline is mediated by alpha-adrenoceptors, the positive chronotropic and inotropic effects by phenylephrine are mediated by beta-adrenoceptors, and alpha-adrenoceptors mediated the inhibitory chronotropic responses exists in the isolated frog atria.