The effect of benzalkonium chloride in the damage of the myenteric plexus of lower esophagus in rats

Abstract

Objective To establish the appropriate animal model of achalasia in the cardia and to observe the effect of Benzalkonium Chloride(BAC) in the damag of the myenteric plexus of lower esophagus in rats and the changes of neurons at different time points.Methods Eighty male SD rats were randomly divided into two experimental groups (40 rats respectively in the BAC group and control groups).The 0.4% benzalkonium chloride was applied on the lower esophagus for 30 minutes during the laparotomy on rats.The changes of the neuron in lower esophagus were observed under microscope after sacrifice of rats at 1,2,4 and 8 weeks respectively.Results One week after the operation,degeneration and necrosis were observed in parts of the neurons and the nerve fibers in the myenteric plexus of lower esophagus in the BAc group.Two weeks after the operation,density of neurons in BAC group was 1.25±0.71 neurons per cross section,which was significantly lower than that in the control group (5.38±2.33 neurons per cross section).Further decreasing of the number of neurons was observed at 4 and 8 weeks after the operation with rio significant differences compared with that at 2 weeks (P＞0.05).Non-selective damage caused by BAC to the neurons with different neurotransmitte could be noted in lower esophagus.Conclusions The 0.4% BAC can damage the neurons of myenteric plexus in lower esophagus in rats,which can be applied to the experimental study of achalasia of cardia. Key words: Achalash; Myenteric plexus; Benzalkonium chloride