가토의 근위와 원위대장 평활근의 운동성 비교

Comparision of Proximal and Distal Large Intestinal Motility in Rabbit

To validate the comparision of proximal and distal large intestinal motility, the amplitude and frequency of spontaneous motility, the effect of acetylcholine, the effect of atropine on the response of acetylcholine, the effect of histamine and the effect of pyrilamine and cimetidine on the response of histamine were investigated in rabbit. The results were summarized as follows: 1. The amplitude of spontaneous motility was more powerful on the proximal large intestine than that of the distal large intestine, but the frequency of spontaneous motility was similar on the both proximal and distal large intestine in rabbit. 2. Acetylcholine caused the contraction of proximal and distal large intestine, and the contractile response were increased between the concentration of acetylcholne $10^{-9}$ and $5{\times}10^{-6}M$ and $10^{-7}$ and $10^{-4}M$ on the proximal and distal large intestine, respectively, with dose-dependent manner in rabbit. 3. The contractile response induced by acetylcholine was completely blocked by the post-treatment with cholinergic receptor blocker, atropine $10^{-6}M$. 4. Histamine caused the contraction of proximal and distal large intestine and the contractile response were increased between the concentration of histamine $10^{-9}$ and $5{\times}10^{-5}M$ and $10^{-5}$ and $10^{-3}M$ on the proximal and distal large intestine, respectively, with dose-depend ent manner in rabbit. 5. The contractile response induced by histamine was completely blocked by the pretreatment with $H_1$-receptor blocker, pyrilamine $10^{-6}M$, but not blocked by the pretreatment with $H_2$-receptor blocker, cimetidine $10^{-6}M$.