Cholera toxin-sensitive neurons in guinea pig submucosal plexus.
Cholera toxin-sensitive neurons in guinea pig submucosal plexus.
复制标题
豚鼠粘膜下丛中的霍乱毒素敏感神经元。
DOI：
10.1152/ajpgi.1993.264.1.g86
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Surprenant,A
中科院分区：
文献类型：
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作者：
Jiang,MM;Kirchgessner,A;Gershon,MD;Surprenant,A
霍乱毒素（CT）通过直接刺激粘膜肠细胞增加肠道分泌；肠神经元也可能发挥作用。我们通过用 CT B 亚基（B-CT）对豚鼠小肠粘膜末端进行逆行标记，并通过 CT 灌注期间粘膜下神经元的细胞内记录来测试后一种可能性。所有血管活性肠肽 (VIP) 阳性神经元，以及仅 VIP 阳性神经元，均用 B-CT 标记。在B-CT标记粘膜末梢的制剂中，使用氟金（FG）逆行标记粘膜下小动脉的神经末梢；在距 FG 应用部位最远 3 mm 的神经元中观察到 B-CT 与 FG 的共定位。 CT 选择性地使已知含有 VIP 的神经元去极化。我们得出的结论是，豚鼠粘膜下神经丛中所有含有 VIP 的神经元（并且只有 VIP 神经元）都具有 B-CT 结合位点，并且可以被 CT 激活。其中一些神经元为小动脉和粘膜提供双重神经支配。我们认为 CT 的功能性后果之一可能是激活血管舒张神经，从而增加粘膜的血管灌注，进一步刺激肠道分泌。
Cholera toxin (CT) increases intestinal secretions by direct stimulation of mucosal enterocytes; enteric neurons also may play a role. We tested the latter possibility by retrograde labeling of mucosal terminals in guinea pig small intestine with the B subunit of CT (B-CT) and by intracellular recordings from submucosal neurons during superfusion with CT. All vasoactive intestinal peptide (VIP)-positive neurons, and only VIP-positive neurons, were labeled with B-CT. Fluorogold (FG) was used to retrogradely label nerve terminals in submucosal arterioles in preparations in which B-CT labeled mucosal terminals; colocalization of B-CT with FG was observed in neurons up to 3 mm from the site of FG application. CT selectively depolarized neurons known to contain VIP. We conclude that all VIP-containing neurons, and only VIP neurons, in guinea pig submucosal plexus possess B-CT binding sites and can be activated by CT. Some of these neurons provide a dual innervation to both arterioles and mucosa. We suggest that one functional consequence of CT may be to activate vasodilator nerves, thus increasing vascular perfusion of the mucosa to further stimulate intestinal secretions.