Effects Of Esophageal Distention On The Expression Of Sense-related Excitatory Neurotransmitters

Objectives: To observe the expression of excitatory neurotransmitters in the esophagus and central nervous systerm(CNS) of rabbits stimulated by esophageal distention before and after intragastric administration of tegaserod, and to explore the role of neurotransmitters and CNS in the esophageal sense.Methods: (1) Low esophageal distention was performed by a balloon in rabbits. The esophageal visceral sense was assessed by animal activity scores. The expression of SP, CGRP, 5-HT, c-fos was measured by immunochistochemistry to explore the role of them and CNS in the esophageal visceral sense. (2) The rabbits stimulated by esophageal distention received tegaserod at different doses. The animal activity scores and expression of SP, CGRP, 5-HT, c-fos were observed to study the effect of tegaserod on esophageal visceral sense.Results: The balloon diameter threshold of esophageal distention group was significant lower than those of control group( P<0.05). Compared with control group, the expression of SP, CGRP, 5-HT, c-fos was significant increased in esophagus mucosa and CNS( P<0.05). After treatment with tegaserod, the threshold of balloon diameter in esophageal distention group was increased markedly. Moreover, the level of SP, CGRP, 5-HT, c-fos in the esophageal mucosa and spine were decreased markedly, there were significant difference( P<0.05).Conclusion: Esophageal hypersensitivity may be induced by esophageal distention. The expresstion of SP, CGRP, 5-HT, c-fos was increased in the esophageal mucosa and CNS. These results indicated that these neurotransmitters and CNS may may play an important role in the esophageal visceral sense. Administration of tegaserod may inhibit the epresstion of SP, CGRP, 5-HT and degrade the esophageal visceral sensitivity.