Choline과 choline esters인 acetylcholine, methacholine, carbachol, bethanechol이 토끼의 적출장관 운동에 미치는 영향과 각 약물의 $pD_2$값을 산출하여 각각 비교를 하였다. Choline은 최대유효농도가 $10^{-2}M$이었으며 $ED_{50}$은 $2.4{ imes}10^{-3}M$이었고 $pD_2$값은 2.619이었다. Acetylcholine은 최대유효농도가 $10^{-4}M$이었으며 $10^{-9}M$에서는 거의 효과가 나타나지 않았고 $ED_{50}$은 $0.5{ imes}10^{-5}M$이었고 $pD_2$값은 5.154이었다. Methacholine은 최대유효농도가 $10^{-5}M$이었으며 $10^{-9}M$에서는 거의 효과가 나타나지 않았고 $ED_{50}$은 $9{ imes}10^{-5}M$이었고 $pD_2$값은 6.045이었다. Carbachol은 최대유효농도가 $10^{-5}M$이었으며 $10^{-11}M$에서는 거의 효과가 나타나지 않았고 $ED_{50}$은 $5.7{ imes}10^{-7}M$이었고 $pD_2$값은 6.244이었다. Bethanechol은 최대유효농도가 $10^{-4}M$이었으며 $10^{-8}M$에서는 거의 효과가 나타나지 않았고 $ED_{50}$은 $3.3{ imes}10^{-6}M$이었고 $pD_2$값은 5.480이었다. Choline esters는 토끼의 적출장관 운동에 대하여 수축을 일으켰으며 각 약물의 potency의 순서는 carbachol이 가장 강하게 나타났고 methacholine, bethanechol, acetylcholine, choline의 순으로 나타났다.
The effects of choline and choline esters(acetylcholine, methacholine, carbachol, bethanechol) on motility of isolated rabbit jejunum segment were examined and $pD_2$ values of each drugs were compared. The results were as follows. In choline, there were revealed that maximum effective concentration was $10^{-2}M$, $ED_{50}$ was $2.4{ imes}10^{-3}M$, and $pD_2$ value was 2.619. In acetylcholine, there were revealed that maximum effective concentration was $10^{-4}M$, effect was hardly showin in $10^{-9}M$ concentration, $ED_{50}$ was $0.5{ imes}10^{-5}M$, and $pD_2$ value was 5.154. In methacholine, there were revealed that maximum effective concentration was $10^{-5}M$, effect was hardly shown in $10^{-9}M$ concentration, $ED_{50}$ was $9{ imes}10^{-7}M$, and $pD_2$ value was 6.045. In carbachol, there were revealed that maximum effective concentration was $10^{-5}M$, effect was hardly shown in $10^{-11}M$ concentration, $ED_{50}$ was $5.7{ imes}10^{-7}M$, and $pD_2$ value was 6.244. In bethanechol, there were revealed that maximum effective concentration was $10^{-4}M$, effect was hardly shown in $10^{-8}M$ concentration, $ED_{50}$ was $3.3{ imes}10^{-6}M$, and $pD_2$ value was 5.480. Choline and choline esters caused contraction on motility of isolated rabbit jejunum segment. The order of $pD_2$ values of drugs was carbachol, methacholine, bethanechol, acetylcholine and choline (in the descending order of potency).
