Developmental anomalies of the enteric nervous system in normoganglionic segments of bowel from rats with total colonic aganglionosis.

Polysialyated neural cell adhesion molecule (PSA-NCAM) is a marker for immature neurons and S100 beta is a known marker for enteric glia. The aim of this study was to determine the maturation of the enteric nervous system (ENS) in normoganglionic (Ng) bowel from rats with total colonic aganglionosis (TCA). Ng ileum was obtained from TCA rats (spotting lethal: mutant, sl/sl: n = 15) at 10, 19, and 24 days of age (n = 5 for each age). Normal control Ng ileum was obtained from wild type littermates (+/+, n = 25) at 10, 19, 24, 30, and 60 days of age (n = 5 for each age). Specimens were studied with immunohistochemistry for PSA-NCAM and S100 beta. On H-E staining, normal mature ganglion cells (GC) were identified in submucus and myenteric plexuses in all specimens from TCA rats and normal controls. For PSA-NCAM, submucus and myenteric GC in control ileum were strongly positive at 10 days old, weakly positive at 19 days old, and did not stain from 24 days old and after. However, in all ileum specimens from TCA rats, both submucus and myenteric GC were strongly positive for PSA-NCAM regardless of age. For S100 beta, submucus and myenteric glial cells in control ileum were negative at 10 and 19 days old, but positive from 24 days old and after. However, in all ileum specimens from TCA rats, submucus and myenteric glial cells were S100 beta negative regardless of age. Our results suggest that GC in the Ng segment of TCA rats remain immature beyond an age when they should be mature.