The role of nitric oxide（NO） and interstitial cell of Cajal（ICC） in the pathogenesis of achalasia

Abstract

Objective To investigate the correlationship between the nitric oxide（NO） and interstitial cell of Cajal（ICC） and achalasia （AC） and the pathogenesis of AC. Methods A total of 16 patients with AC who visited endoscopy center of the Zhongshan Hospital from August 2011 to December 2011were enrolled as the experimental group. The specimens of experimental group were obtained by biopsy of lower esophageal sphincter during peroral endoscopic myotomy（POEM） procedure. The 15 lower esophageal sphincter（LES） surgical specimens of non-esophageal motility disorders were enrolled as the control group. All specimens were made into paraffin sections and were examined by immunohistochemical staining method. The distribution of ICC and expression of nitric oxide synthase （NOS） under light microscope were observed. ICC was calculated and the staining intensity of NOS was semi-quantitatively evaluated in selected fields of vision at random. Results Under light microscope, ICC distributed and NOS was expressed in the LES. ICC was fusiform with two elongated apophysis. ICC was linked by apophysis and parallelly distributed with smooth muscle cells. The density of ICC in the experimental group was reduced and apophysis was less obvious com-pared with that in control group with significant differences （ 5.8 ± 5.6 VS 11.2 ± 7.4, P = 0. 01 ）. Likewise, NOS positive nerve fibers was visible in LES. NOS positive nerve fibers were absent and the strength of staining was weaker in AC group compared with that in control group with significant differences （P = 0. 13 ）. Conclusion Abnormal distribution of ICC and NOS in LES may be correlated with AC. Key words: Esophageal achalasia; Interstitial cell of Cajal; Nitric oxide synthase