Differential effect of immunosympathectomy on the expression of rat enteric neurotransmitters.

The effect of immunosympathectomy on the pattern of distribution of catecholamine- and peptide-containing nerve fibres and neurones in the myenteric and submucous plexuses of rat ileum was investigated. There was an increase in vasoactive intestinal polypeptide (VIP)-, galanin (GAL)- and substance P-like immunoreactivity in the myenteric plexus of ileum from rats treated with nerve growth factor (NGF) antiserum compared with controls. A similar increase in immunoreactivity was observed in VIP-, GAL- and neuropeptide Y (NPY)-containing submucous neurones and nerve fibres. In contrast, the immunosympathectomy had no effect on the pattern of distribution of catecholamine-, calcitonin gene-related peptide (CGRP)- and NPY-containing nerve fibres in the myenteric plexus or on substance P- and CGRP-containing neurones and nerve fibres of the submucous plexus. The findings of the present study suggest that NGF may differentially regulate the expression of enteric neuropeptides at a postnatal stage of development.