胃动素对消化间期胃动脉血流影响的在体机制研究

目的此研究目的在于试图揭示胃动素对消化间期意识清醒狗胃动脉血流影响的调节机制。方法 5条意识清醒狗的胃左动脉（LGA）血流通过超声波传输时间血流仪（ultrasound transit-time blood flow meters）进行了测定。在有或无GM-109（Phe-cyclo[Lys-Tyr（3-tBu）-βAla.trifluoroacetate,胃动素受体拮抗剂）,granisetron（5HT3受体拮抗剂）,at-ropine（M胆碱能受体阻滞剂）,hexamethonium（N胆碱能受体阻滞剂）,phenoxybenzamine（α-肾上腺素能受体阻滞剂）和propranolol（β-肾上腺素能受体阻滞剂）分别静脉内持续性滴注的前提下,反复静点胃动素进行实验。结果消化间期,胃动素（100 pmol/kg/h）诱导了LGA血流的增加。GM-109完全抑制了由胃动素引起的LGA血流增加和胃肠运动。At-ropine、C6、granisetron抑制了胃动素诱导的胃运动,但未能影响LGA血流的持续性增加。α-肾上腺素能受体阻滞剂和β-肾上腺素能受体阻滞剂对胃动素诱导的LGA血流和胃机械性收缩无影响。结论胃动素是一个有效的胃血管舒张剂,胃动素通过胃动脉壁上胃动素受体调节消化间期胃动脉血流。胃动素在消化间期胃血流的调节中起着一个非常重要的作用。

A study on effects of motilin on interdigestive gastric arterial blood flow mechanism in vivo

Objective Aim The aim of this study is to clarify the regulatory role of motilin in interdigestive gastric blood flow in conscious dogs.Methods Blood flow of the left gastric（LGA） arterie was measured by ultrasound transit-time blood-flow meters in 5 conscious dogs.Motilin was infused intravenously with or without phe-cyclo [Lys-Tyr（3-tBu）-βAla-] ·trifluoroacetate（GM-109;motilin antagonist）,granisetron（5-HT3 antagonist）,atropine,hexamethonium（C6）,phenoxybenzamine,propranolol,or cimetidine.Results Motilin（100 pmol·kg-1·h-1） induced LGA blood-flow increase.GM-109 completely abolished the LGA blood flow and motility responses to motilin（100 pmol·kg-1·h-1）.Atropine,granisetron and C6 abolished motilin-induced gastric contractions,but failed to affect the sustained LGA blood flow.The LGA flow and gastric motility responded to motilin were not inhibited by α-adrenergic and β-adrenergic blockers.Conclusion Motilin has a potent gastric vasodilator effect,and appears to regulate interdigestive gastric arterial blood flow by the motilin receiver on gastric arterial wall.Motilin plays an important role in the regulation of interdigestive gastric blood flow in dogs.