关键词: 神经递质 , 离子通道, 神经节内板状末梢, 机械感受器, FM1-43

Abstract: Objective: To investigate the structure and characteristics of mechanotransduction by intraganglionic laminar endings (IGLEs) as the mechanoreceptors in rat gut. Methods: ① IGLEs were displayed by styryl dye FM1-43 with stretch stimulation to the rat esophagus. P2X2 immunohistochemistry staining was used to confirm that the structure displayed by FM1-43 was that of IGLEs; ② Different drugs （TTX, Ca2+, Benzamil, Capsaicin, and α，β- meATP）were used to block or stimulate stretchevoked IGLEs staining by FM1-43 for further investigating the mechanism of mechanotransduction by IGLEs. Results: ① The amount of IGLEs displayed by stretchevoked FM1-43 staining was much more than that without stretch stimulation (P<0.01). The structure of IGLEs displayed by FM1-43 was consistent with that by P2X2; ② TTX, Ca2+ had no effect on stretchevoked IGLEs staining, while benzamil could significantly block it. Caqsaicin could activate the entrance of FM1-43 into IGLEs without any stretch, while α，β- meATP, and the potent ATP anologue could not stimulate the staining at rest status. Conclusion: ① IGLEs are the mechanoreceptors of vagal afferent endings in the gut; ② IGLEs transduce the mechanical stimulation in the gut through some mechanosensitive ion channels which are a type of sodium ion channels. Neurotransmitters or action potentials are not involved in this process.

Key words: FM1-43, Intraganglionic laminar endings, Mechanoreceptors, Ion channels, Neurotransmitters