Manometric evaluation of children with chronic constipation using a suction-stimulating electrode

Postnatal development of the mucosal plexus in the porcine small and large intestine

Knowledge regarding the foetal and postnatal development of the enteric nervous system is crucial for the understanding of congenital disorders. While lot of information exists regarding the myenteric and submucosal plexuses, the development of the mucosal plexus has not been previously studied. The mucosal innervation seems to play an important role in the local reflex activity of the gut. In this study, we examined the development of enteric mucosal innervation in the pig at various ages of life. Small and large bowel paraffin-embedded specimens were stained with PGP 9.5 and neurofilament protein in three piglets from six age groups (60 and 90 days gestation, newborn, 4 and 12 weeks old, and adult pigs). Small and large bowel demonstrated identical innervation patterns. Myenteric and submucosal plexuses were stained with PGP 9.5 at 60 days gestation. However, the mucosal staining was first noted clearly at the newborn period. By 4 weeks, PGP 9.5 staining was noted in small amounts within the mucosa. Inner proprial and villous fibres were seen ahead in time to the subepithelial fibres. Both inner proprial and villous staining became quiet prominent by 12 weeks of age and remained unchanged into adulthood. However, the subepithelial fibres appear to increase in adulthood. This study demonstrates for the first time that enteric mucosal innervation first appears only at birth. The immaturity of the mucosa generated reflex activity, and secretory functions may have implication in the management of functional intestinal obstruction in the premature infant.

Abnormalities in visceral evoked potentials from the anal canal in children with chronic constipation

The integrity of the sensory nervous system in the anal canals of chronically constipated children was investigated using evoked potential techniques examining cerebral and spinal evoked potentials from the lower extremities and anal canal. Stimulation of the posterior tibial nerve produced no significant difference in the parameters of spinal and cerebral evoked potentials between 18 controls and 12 chronically constipated children. However, stimulation of the anal canal resulted in evoked potentials related to the age and/or consciousness level of the control children. Reproducible cerebral responses were obtained only from nine of these control children, all aged over 4 years, who were examined while awake without sedatives. A typical response was characterized by a polyphasic wave occurring with an onset latency of 79.4 +/- 27.7 ms (mean +/- SD). In the 12 chronically constipated children, the 5 sedated patients examined while asleep did not show any reproducible potential, as in the controls. However, in the remaining 7 children examined while awake, the occurrence of the anal canal evoked potential was significantly reduced, and only two exhibited a cerebral response. These findings suggest that rectal mucosal perception of the intraluminal stimuli might be disturbed in some children with chronic constipation.