Action of pituitary adenylate cyclase-activating polypeptide on ion transport in guinea pig distal colon.
Action of pituitary adenylate cyclase-activating polypeptide on ion transport in guinea pig distal colon.
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垂体腺苷酸环化酶激活多肽对豚鼠远端结肠离子转运的作用。
DOI：
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发表时间：
1993
影响因子：
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通讯作者：
N. Yanaihara
中科院分区：
文献类型：
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作者：
A. Kuwahara;Y. Kuwahara;T. Mochizuki;N. Yanaihara
本研究的目的是观察垂体腺苷环化酶激活多肽(PACAP)对豚鼠远端结肠离子转运的影响。将来自远端结肠的粘膜下/粘膜节段安装在Ussing通道室中，短路电流(ISC)的增加作为分泌的指标。血清中加入PACAP-38和PACAP-27后，ISC呈浓度依赖性(10(-10)-10(-6)M)增加。速尿和无氯溶液显著降低了PACAP诱发的反应。河豚毒素(TTX)可完全阻断PACAP诱发的反应。阿托品可显著降低PACAP诱发的反应，但不能取消这种反应。结果提示，PACAP通过胆碱能和非胆碱能神经机制引起氯的分泌。血管活性肠多肽(VIP)、组氨酸-异亮氨酸酰胺和Helodermin以浓度依赖的方式引起ISC。阿托品减少但不能消除VIP和相关多肽引起的反应。TTX也显着降低对高浓度VIP和相关多肽的反应，但不能取消这种反应。结果表明，VIP及其相关多肽对粘膜下神经元和上皮细胞本身均有作用。VIP快速止痛显著降低PACAP-38和PACAP-27诱发的反应。这些结果证明，PACAP部分识别粘膜下神经元中的VIP受体，从而引起氯的分泌。
The aim of the present study was to investigate the action of pituitary adenylate cyclase-activating polypeptide (PACAP) on ion transport in the guinea pig distal colon. Submucosal/mucosal segments from distal colon were mounted in Ussing flux chambers, and increases in short-circuit current (Isc) were used as an index of secretion. Serosal addition of PACAP-38 and PACAP-27 produced concentration-dependent (10(-10)-10(-6) M) increases in Isc. Furosemide and chloride-free solutions significantly reduced the PACAP-evoked responses. Tetrodotoxin (TTX) completely blocked PACAP-evoked responses. Atropine significantly reduced the PACAP-evoked responses but did not abolish the responses. The results suggest that PACAP evokes chloride secretion through cholinergic and noncholinergic neural mechanism. Vasoactive intestinal polypeptide (VIP), peptide histidine-isoleucine amide, and helodermin evoked Isc in a concentration-dependent manner. Atropine reduced but did not abolish the VIP- and related peptides-evoked responses. TTX also significantly decreased the responses to higher concentrations of VIP and related peptides but did not abolish the responses. The results suggest that VIP and related peptides act on both submucosal neurons and the epithelial cell itself. VIP tachyphylaxis significantly decreased PACAP-38- and PACAP-27-evoked responses. These results provide evidence that PACAP recognizes, in some part, VIP receptors in the submucosal neurons to evoke chloride secretion.