Jinan, China

Author Affiliations: Department of Pediatric Surgery, Qilu Hospital of Shandong University, Jinan 250012, China (Li AW, Zhang WT); Key Lab of Cardiovascular Functional and Remodeling Research of Ministry of Education and Health, China (Wang R, Feng JB); Department of Microbiology of Medical Collage of Shandong University, China (Ruan Y)

Corresponding Author: Wen-Tong Zhang, Department of Pediatric Surgery, Qilu Hospital of Shandong University, Jinan 250012, China (Tel: 86-531-82169400; Email: liaiwuxie@yahoo.com.cn)

Background: The cause of Hirschsprung's disease (HD) remains unclear, but currently there are two theories: the mutation of the RET gene and the change of enteric microenvironment. This study was undertaken to elucidate the cause of HD by assessing the expression of laminin (LN), laminin gene, and the RET gene in the aganglionic segment, transitional zone and normal segment of the colon in patients with HD. 

Methods: Specimens of the aganglionic segment, transitional zone, and normal segment of the colon from 27 cases of HD were stained immunohistologically by a PV 9000 polymer detection system. Photos were taken by the RS image system, and the staining area of each image was calculated by a JD 801 image analysis system. The qualitative expressions of the laminin gene and RET gene of these three segments in the 27 cases were detected by reverse transcription-polymerase chain reaction (RT-PCR), and the difference of the expressions was shown by the alpha 9900 image analysis system. The quantitative expressions of the laminin gene and RET gene in the three segments were detected by real-time quantitative PCR, and the difference of the expression was shown by SDS software.

Results: The laminin and laminin gene were expressed in all the three segments. The expression was higher in the aganglionic segment than in the dilated segment, and the expression decreased stepwisely from the aganglionic segment to the normal segment, while the expression of the RET gene was opposite, showing an increased segmenting from the aganglionic segment to the normal segment. The correlation between the expressions of the two genes was negatively correlated.

Conclusions: The highly increased expression of LN in the aganglionic segment may cause early differentiation, early maturation and premature ecesis of enteric nervous cells. The change of the microenvironment of colon wall may be the cause of HD. The negative correlation between the expression of the two genes may be closely related to the occurrence of HD.

Key words: gene expression; Hirschsprung's disease; laminin; RET

World J Pediatr 2008;4(2):135-139