Sawa T, Mameya S, Yoshimura M, Itsuno M, Makiyama K, Niwa M, Taniyama K
Department of Internal Medicine II, Nagasaki University School of Medicine, Japan.
Eur J Pharmacol. 1995 Apr 4;276(3):223-30. doi: 10.1016/0014-2999(95)00024-f.
The effect of peptide YY on contractility, acetylcholine release and noradrenaline release was examined in the isolated guinea-pig colon, and findings were compared with those for neuropeptide Y. Peptide YY and neuropeptide Y inhibited the twitch contractions mediated by the stimulation of cholinergic neurons. Peptide YY, neuropeptide Y, [Leu31,Pro34]neuropeptide Y and neuropeptide Y-(13-36) inhibited the electrically stimulated release of acetylcholine. Neuropeptide Y, but not peptide YY, inhibited the high K(+)-stimulated tetrodotoxin-resistant release of acetylcholine, while the inhibitory effect of neuropeptide Y disappeared after treatment with yohimbine. Neuropeptide Y, but not peptide YY or neuropeptide Y analogues, evoked the release of noradrenaline. After desensitization to the effects of neuropeptide Y, peptide YY inhibited electrically stimulated acetylcholine release. Thus, peptide YY inhibits acetylcholine release through stimulation of a receptor, distinct from the site of action of neuropeptide Y, located on cholinergic neurons as well as the neuropeptide Y Y1 and Y2 receptors in the guinea-pig colon. Neuropeptide Y inhibits acetylcholine release due to the noradrenaline release mediated by stimulation of a receptor distinct from neuropeptide Y Y1 and Y2 receptors, located on adrenergic neurons.
在离体豚鼠结肠中研究了肽YY对收缩性、乙酰胆碱释放和去甲肾上腺素释放的影响，并将结果与神经肽Y的结果进行比较。肽YY和神经肽Y抑制由胆碱能神经元刺激介导的抽搐收缩。肽YY、神经肽Y、[Leu31，Pro34]神经肽Y和神经肽Y-(13-36)抑制电刺激引起的乙酰胆碱释放。神经肽Y而非肽YY抑制高钾刺激的对河豚毒素不敏感的乙酰胆碱释放，而用育亨宾处理后神经肽Y的抑制作用消失。神经肽Y而非肽YY或神经肽Y类似物引起去甲肾上腺素释放。对神经肽Y的作用脱敏后，肽YY抑制电刺激的乙酰胆碱释放。因此，肽YY通过刺激位于豚鼠结肠胆碱能神经元以及神经肽Y Y1和Y2受体上与神经肽Y作用位点不同的受体来抑制乙酰胆碱释放。神经肽Y由于刺激位于肾上腺素能神经元上与神经肽Y Y1和Y2受体不同的受体介导的去甲肾上腺素释放而抑制乙酰胆碱释放。
