Ito S, Ohta T, Nakazato Y, Ohga A, Yanaihara N
Jpn J Pharmacol. 1986 Mar;40(3):423-34. doi: 10.1254/jjp.40.423.
Experiments were carried out to investigate whether avian pancreatic peptide (APP) antagonized relaxations of vascular and gastrointestinal smooth muscles induced by vasoactive intestinal peptide (VIP) and non-adrenergic, non-cholinergic inhibitory nerve stimulation using the cat submandibular gland, cat colon and dog stomach in vivo and several isolated smooth muscles in vitro. APP caused a dose-dependent inhibition of an atropine-resistant vasodilatation induced by chorda-lingual and pelvic nerve stimulation and by VIP. APP did not reduce VIP output induced by pelvic nerve stimulation. APP shifted the dose-response curve for VIP and the frequency-response curve for pelvic nerve stimulation to the right. The vasodilatation induced by isoproterenol or bradykinin was inhibited by somewhat higher doses of APP. APP failed to inhibit the vago-vagal reflex relaxation of the dog stomach. In guinea pig and rat fundic strips and in isolated chick rectum, APP did not exert any significant effects on relaxation caused by VIP or transmural stimulation in the presence of atropine and guanethidine. The result indicates that APP inhibits VIP-mediated relaxation of the vascular smooth muscle, but not that of the gastrointestinal smooth muscle. The inhibitory effect of APP on VIP-mediated vasodilatation is suggested to be due to the physiological competition.
采用猫下颌下腺、猫结肠和犬胃进行体内实验，并利用几种离体平滑肌进行体外实验，以研究禽胰多肽（APP）是否能拮抗血管活性肠肽（VIP）以及非肾上腺素能、非胆碱能抑制性神经刺激所诱导的血管和胃肠道平滑肌舒张。APP对由鼓索舌神经和盆神经刺激以及VIP所诱导的阿托品抵抗性血管舒张产生剂量依赖性抑制作用。APP并未降低盆神经刺激所诱导的VIP释放量。APP使VIP的剂量-反应曲线以及盆神经刺激的频率-反应曲线右移。异丙肾上腺素或缓激肽所诱导的血管舒张受到稍高剂量APP的抑制。APP未能抑制犬胃的迷走-迷走反射性舒张。在豚鼠和大鼠胃底条以及离体鸡直肠中，在存在阿托品和胍乙啶的情况下，APP对由VIP或跨壁刺激所引起的舒张未产生任何显著影响。结果表明，APP抑制VIP介导的血管平滑肌舒张，但不抑制胃肠道平滑肌舒张。APP对VIP介导的血管舒张的抑制作用被认为是由于生理性竞争所致。
