Mukai T, Kubota K
Eur J Pharmacol. 1980 Jul 25;65(2-3):157-63. doi: 10.1016/0014-2999(80)90388-x.
The differences in contractile responses to acetylcholine (ACh) and serotonin (5-HT) were studied in the rat fundus strips. At low temperatures, the contractile response to 5-HT was reduced more noticeably than to ACh. The contraction induced by ACh at 4 degrees C was not inhibited by La3+. Removal of extracellular Ca2+ reduced the response to 5-HT more significantly than that to ACh.. La3+, verapamil and D-600 inhibited the 5-HT response more than the ACh response. In Ca2+-free solution the contractile response to ACh of a fundus strip preloaded with Ca2+ was lar ger than that to 5-HT. These results suggest that the Ca2+ movements induced by ACh and by 5-HT are different, and that the difference in Ca2+ movements may cause the difference in contractile responses to the two agonists at low temperatures.
在大鼠胃底条上研究了对乙酰胆碱（ACh）和5-羟色胺（5-HT）收缩反应的差异。在低温下，对5-HT的收缩反应比对ACh的收缩反应更明显地降低。4℃时ACh诱导的收缩不受La3 +抑制。去除细胞外Ca2 +对5-HT反应的降低比对ACh反应的降低更显著。La3 +、维拉帕米和D-600对5-HT反应的抑制比对ACh反应的抑制更明显。在无Ca2 +溶液中，预加载Ca2 +的胃底条对ACh的收缩反应大于对5-HT的收缩反应。这些结果表明，ACh和5-HT诱导的Ca2 +运动不同，并且Ca2 +运动的差异可能导致在低温下对两种激动剂收缩反应的差异。
