豚鼠肠系膜下神经节细胞的5-HT_(1P)受体介导的慢去极化反应(英文)

5-HT_(1P) receptor-mediated slow depolarization in neurons of guinea pig inferior mesenteric ganglion

观察不同５－羟色胺（５－ＨＴ）受体亚型拮抗剂对５－ＨＴ去极化反应的作用，并观察５－ＨＴ１Ｐ受体激动剂对肠系膜下神经节（ＩＭＧ）细胞膜电位的作用．方法：离休豚鼠ＩＭＧ细胞内生物电记录．结果：赛庚啶（５－ＨＴ１／２受体拮抗剂 １０ μｍｏｌ·Ｌ－， ｎ＝７）和ＢＲＬ ２４９２４（５－ＨＴ１Ｐ受体拮抗剂 １０ μｍｏｌ·Ｌ－１， ｎ＝１９）可逆地阻抑５－ＨＴ慢去极化反应；压力注射ＭＣＰＰ（５－ＨＴ１Ｐ受体激动剂 １０ ｍｍｏｌ· Ｌ－１）则使大部分５－ＨＴ敏感细胞出现慢去极化反应（１０／１４）结论：５－ＨＴ慢去极化反应是由５－ＨＴ１Ｐ受体介导．

AIM: To study the effects of several 5- hydroxytryptamine (5-HT) receptor subtype antagonists on 5-HT-induced depoledzation and the effects of 5-HT_(1P) receptor agonist on the membrane potential in the neurons of guinea pig inferior mesenteric ganglion (IMG). METHODS: Intracellular recordings were made from neurons of the isolated guinea pig IMG. RESULTS: Cyproheptadine (5-HT1/2 antagonist 10 μmol· L-1, n = 7) and BRL 24924 (5-HT_(1P) antagonist 10 μmol·L-1, n = 19) reversibly suppressed 5-HT slow response; pressure ejection of MCPP (5-HT_(1P) agonist 10 mmol· L-1 ) induced a slow depolarization in most of 5-HT sensitive neurons (10/14). CONCLUSION: 5-HT-induced slow depolarization is mediated by 5-HT1P receptor.