Idiopathic constipation is not associated with increased NCAM expression on intestinal muscle.

Our previous study of neural cell adhesion molecule (NCAM) in childhood Hirschsprung's disease demonstrated increased expression on intestinal muscle, especially muscularis mucosae, in aganglionic bowel. The present study was undertaken to test whether this increased NCAM expression is a feature of congenital aganglionosis rather than being a nonspecific feature of constipation. We studied specimens from six patients (20-60 years old; five women and one man) operated on for idiopathic long-standing constipation, using immunocytochemistry for NCAM and protein gene product 9.5 (PGP 9.5). Results showed that in adult constipated bowel the pattern of NCAM expression is similar to that seen in controls. There was no expression of NCAM on muscle in any of the specimens studied. Thus, it seems likely that increased NCAM expression in gastrointestinal smooth muscle in congenital aganglionosis is a result of the abnormal innervation rather than any symptomatic or clinical feature.