Opiate nerves mediate feline pyloric response to intraduodenal amino acids.
Opiate nerves mediate feline pyloric response to intraduodenal amino acids.
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阿片神经介导猫幽门对十二指肠内氨基酸的反应。
DOI：
10.1152/ajpgi.1985.248.3.g307
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发表时间：
1985
期刊：
影响因子：
--
通讯作者：
Cohen,S
中科院分区：
文献类型：
--
作者：
Reynolds,JC;Ouyang,A;Cohen,S
记录了猫的胃窦、幽门和十二指肠对十二指肠内氨基酸溶液的反应，记录了腔内压力和肌电活动。与生理盐水对照组相比，混合氨基酸（0.02 mg/ml, 3.0 ml）增加了幽门收缩幅度（59.7 +/- 7.9 mmHg）和幽门尖峰活性（73.7 +/- 6.8%的慢波有尖峰活性）（P < 0.001）。这些反应的选择性是用特定的氨基酸确定的。l -色氨酸（10或40 mM）产生的反应类似于混合氨基酸的反应，而l -苯丙氨酸或l -甘氨酸（10或40 mM）没有影响。动脉注射河豚毒素、腔内注射氨基苯甲酸乙酯或静脉注射纳洛酮（1.0 mg/kg）可消除氨基酸的幽门反应（P < 0.02）。双侧宫颈迷走神经切开术无效果。缩胆素八肽（CCK-OP）在幽门收缩振幅和幽门尖峰活性中产生剂量依赖性的增加。CCK-OP的ED50剂量（1.0微克/千克iv）使幽门压增加155.6 +/- 49.9 mmHg，尖峰活性增加77.7 +/- 9.4%，与混合氨基酸或色氨酸相似。然而，通过阻断对亮氨酸-脑啡肽的最大幽门反应的纳洛酮（1.0 mg/kg）剂量，CCK-OP的这些作用并没有被拮抗。我们得出结论，十二指肠内混合氨基酸或色氨酸通过非迷走神经、纳洛酮敏感的神经通路增加猫的相位性、峰依赖性幽门收缩，苯丙氨酸（一种结构相似的必需氨基酸）对猫的胃十二指肠连接处没有影响，幽门对外源性CCK-OP的反应是通过与色氨酸或混合氨基酸不同的途径介导的。
Intraluminal pressures and myoelectric activity were recorded from the feline antrum, pylorus, and duodenum in response to intraduodenal amino acid solutions. Mixed amino acids (0.02 mg/ml, 3.0 ml) increased the amplitude of pyloric contractions (59.7 +/- 7.9 mmHg) and pyloric spike activity (73.7 +/- 6.8% of slow waves with spike activity) compared with a saline control (P less than 0.001). The selectivity of these responses was determined with specific amino acids. L-Tryptophan (10 or 40 mM) produced a response similar to the mixed amino acid response, while L-phenylalanine or L-glycine (10 or 40 mM) had no effect. Intra-arterial tetrodotoxin, intraluminal ethyl aminobenzoate, or intravenous naloxone (1.0 mg/kg) abolished the pyloric responses to amino acids (P less than 0.02). Bilateral cervical vagotomy had no effect. Cholecystokinin octapeptide (CCK-OP) produced dose-dependent increases in the amplitude of pyloric contractions and in pyloric spike activity. The ED50 dose of CCK-OP (1.0 microgram/kg iv) gave an increase in pyloric pressure of 155.6 +/- 49.9 mmHg and in spike activity of 77.7 +/- 9.4%, similar to mixed amino acids or tryptophan. These effects of CCK-OP were not antagonized, however, by a dose of naloxone (1.0 mg/kg) that blocked the maximal pyloric response to leucine-enkephalin. We concluded intraduodenal mixed amino acids or tryptophan increase phasic, spike-dependent pyloric contractions in the cat via nonvagal, naloxone-sensitive neural pathways, phenylalanine, a structurally similar essential amino acid, had no effect on the feline gastroduodenal junction, and the pyloric responses to exogenous CCK-OP are mediated by pathways distinct from the responses to tryptophan or mixed amino acids.