Aleksandrov A N, Ovsiannikov V I
Fiziol Zh SSSR Im I M Sechenova. 1990 Dec;76(12):1691-700.
The administration of mesaton enhanced contractile activity of pyloric sphincter and diminished it in the duodenum in rabbits. The blockade of alpha-adrenoreceptors with dihydroergotoxin abolished the myoelectrical activity in the pyloric sphincter and sharply enhanced it in the duodenum. Both these effects could occur in the blockade and in the stimulation of alpha-adrenoreceptors of the ileum. The administration of mesaton against the background of the blockade of H-cholinoreceptors with bensohexonium never enhanced myoelectrical activity of the pyloric sphincter. The data obtained suggest different roles of alpha-adrenoreceptors in the pyloric sphincter, duodenum and ileum. The activating alpha-adrenoreceptors of the pyloric sphincter can be found on the neurons of the myenteric plexus.
在兔体内，美速克新命的给药增强了幽门括约肌的收缩活动，而减弱了十二指肠的收缩活动。用双氢麦角毒碱阻断α-肾上腺素能受体可消除幽门括约肌的肌电活动，并使十二指肠的肌电活动急剧增强。这两种效应在阻断和刺激回肠的α-肾上腺素能受体时均可出现。在使用溴本辛阻断H-胆碱能受体的背景下给予美速克新命，从未增强幽门括约肌的肌电活动。所获得的数据表明α-肾上腺素能受体在幽门括约肌、十二指肠和回肠中具有不同作用。幽门括约肌的激活型α-肾上腺素能受体可能存在于肌间神经丛的神经元上。
