Thyrotropin-releasing hormone: an inhibitory regulatory peptide of feline lower esophageal sphincter.
Thyrotropin-releasing hormone: an inhibitory regulatory peptide of feline lower esophageal sphincter.
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促甲状腺激素释放激素：猫下食管括约肌的抑制性调节肽。
DOI：
10.1152/ajpgi.1993.264.3.g522
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Kreider,MS
中科院分区：
文献类型：
--
作者：
Parkman,HP;Reynolds,JC;Ogorek,CP;Kreider,MS
在猫身上检查了促甲状腺激素释放激素 (TRH) 在食管下括约肌 (LES) 中的功能作用。本研究的具体目的是确定：1）TRH 在整个猫胃肠道中的相对分布，2）TRH 对 LES 基础压力的影响及其对外源性收缩的反应。通过放射免疫测定法测定 12 个部位的组织提取物中的 TRH 浓度。通过测压确定的 LES 处 TRH 的平均浓度为 240 +/- 85 pg/g 湿重组织，最大浓度正好位于 LES 远端（659 +/- 189 pg/g 湿重）。粘膜中的 TRH 浓度高于胃底、胃窦、十二指肠和回肠的底层肌肉层。在生理学研究中，通过胃左动脉选择性给予 TRH 对基础 LES 或食管压没有影响。 TRH (2.8 x 10(-8) mol/kg) 使 LES 对 P 物质 D50 的反应降低了 47.2%（34.8 +/- 3.1 至 18.4 +/- 2.9 mmHg，P < 0.01）。在河豚毒素存在的情况下，TRH 对 P 物质诱导的收缩具有类似的抑制作用 (53.5%)。 TRH 还将铃蟾肽诱导的收缩降低了 47.5%（29.6 +/- 6.0 至 15.8 +/- 3.9 mmHg，P < 0.025）。然而，TRH 对氨甲酰甲胆碱引起的收缩没有影响。我们的结论是：1）TRH 存在于整个胃肠道，其中 LES 远端区域浓度最高； 2）TRH对基础LES音调没有影响； 3) TRH 抑制 LES 对内源性释放和外源性物质 P 的反应，但不抑制 LES 对氨甲酰甲胆碱的反应。（摘要截断为 250 字）
The functional role of thyrotropin-releasing hormone (TRH) at the lower esophageal sphincter (LES) was examined in the cat. The specific aims of this study were to determine: 1) the relative distribution of TRH throughout the feline gastrointestinal tract and 2) the effect of TRH on LES basal pressures and its response to exogenously induced contractions. TRH concentrations were determined by radioimmunoassay in tissue extracts from 12 sites. The mean concentration of TRH at the manometrically determined LES was 240 +/- 85 pg/g wet wt tissue, and the maximal concentration was just distal to the LES (659 +/- 189 pg/g wet wt). TRH concentration was higher in the mucosa than the underlying muscle layer of the fundus, antrum, duodenum, and ileum. In physiological studies, TRH given selectively via the left gastric artery had no effect on basal LES or esophageal pressures. TRH (2.8 x 10(-8) mol/kg) decreased the LES response to the D50 of substance P by 47.2% (34.8 +/- 3.1 to 18.4 +/- 2.9 mmHg, P < 0.01). In the presence of tetrodotoxin, TRH gave a similar inhibition of substance P-induced contractions (53.5%). TRH also decreased bombesin-induced contractions by 47.5% (29.6 +/- 6.0 to 15.8 +/- 3.9 mmHg, P < 0.025). TRH, however, had no effect on bethanechol-induced contractions. We conclude that 1) TRH is present throughout the gastrointestinal tract, with highest concentrations in the region distal to the LES; 2) TRH has no effect on basal LES tone; and 3) TRH inhibits the LES response to endogenously released and exogenous substance P but not the LES response to bethanechol.(ABSTRACT TRUNCATED AT 250 WORDS)