摘要: |
目的:研究大鼠禁食状态下甲状腺内胃动素(MTL)对胃肠移行性复合运动(MMC)的影响。方法:采用免疫荧光法、放射免疫法检测MTL在甲状腺组织的表达;采用清醒状态下胃肠运动记录法观察甲状腺内MTL对MMC的调控作用。结果:免疫荧光结果显示,正常甲状腺组织中有MTL免疫阳性反应物(MTL-IR)的表达,且MTL-IR与降钙素(CT)共存,提示MTL表达于甲状腺的C细胞。放射免疫结果显示,十二指肠黏膜有大量MTL表达,其含量分别是甲状腺和胃窦部MTL表达的128.02和100.57倍。大鼠尾静脉注射MTL,胃窦和十二指肠的MMC呈剂量依赖性增加,表现为收缩频率增快(P<0.05,P<0.01)和收缩波幅增大(P<0.05,P<0.01)。静脉注射MTL受体拮抗剂GM109,MMC收缩频率显著减慢(P<0.05),收缩波幅显著变小(P<0.05);GM109可显著阻断MTL的促进MMC作用。摘除一侧甲状腺,MMC周期显著变长,收缩频率显著减慢(P<0.05),收缩波幅显著变小(P<0.05)。甲状腺内注射MTL抗血清,胃窦和十二指肠的MMC运动均显著减少,其收缩频率显著减慢(P<0.05),收缩波幅显著变小(P<0.05)。结论:甲状腺C细胞可表达MTL;甲状腺内MTL参与胃肠MMC的调控。 |
关键词: 消化间期移行性复合运动 胃动素 甲状腺 |
DOI:10.3724/SP.J.1008.2009.01338 |
投稿时间:2009-04-20修订日期:2009-09-09 |
基金项目:国家自然科学基金(30470642,30670780),山东省科技攻关项目 (2008GG10002006),山东省卫生厅项目(2007HZ026)和青岛市科技局项目(05-1-JC-93). |
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Effect of thyroid motilin on migrating motor complex in fasting rats |
CAI Jian-mei,XU Luo* |
(Department of Pathophysiology,Medical College of Qingdao University,Qingdao 266021,China) |
Abstract: |
Objective:To investigate the effects of thyroid motilin (MTL) on migrating motor complex (MMC) in fasting rats.Methods: The distribution and quantitative expression of motilin in the thyroids were detected by immunohistochemistry and radioimmunoassay.We also observed the effect of thyriod motilin on the MMC by recording the gastrointestinal motility in conscious rats.Results: Tail vein injection of MTL increased MMC in antrum and duodenum in a dose-dependent manner,as manifested by increased contraction frequency and amplitude (P<0.05,P<0.01).However,the contraction frequency and amplitude were significantly decreased after injection of MTL-R antagonist GM109(P<0.05).GM109 could obviously block the promoting effect of MTL on MMC.Removing left thyroid significantly increased MMC cycle,contraction amplitude,and decreased contraction frequency(P<0.05). Injection of anti-MTL serum into the thyroids could significantly promote MMC and increase the frequency and amplitude of contraction (P<0.05).Immunohistochemistry demonstrated that motilin immunoreactive (MTL-IR) cells,together with calcitonin (CT),were observed in the thyroids,indicating the expression of MTL in thyroid C-cells.Radioimmunoassay analyses displayed that MTL level in the duodenal mucosa was 128.02 and 100.57 times those in the antrum and thyroid,respectively.Conclusion: MTL is expressed in the thyroid C-cell and participates in the regulation of MMC. |
Key words: interdigestive migrating motor complex motilin thyroid |