LACK OF A DOCKING MECHANISM FOR NEUROTRANSMITTER RELEASE IN THE AGANGLIONIC SEGMENT OF BOWEL IN PATIENTS WITH HIRSCHSPRUNGS-DISEASE

We examined immunohistochemically the expression and localisation of s ynapse-associated proteins, syntaxin (SNT) and synaptotagmin (STG) in the entire resected specimens of colon obtained at the time of pull-th rough operation from 15 patients with Hirschsprung's disease (HD) and 6 age-matched controls. Both antibodies showed a similar pattern of st aining. In the normal colon and ganglionic colon from HD, there was st rong reactivity in the submucous and myenteric plexuses in addition to staining of nerve fibres in the smooth-muscle layers. In the aganglio nic colon, there was an absence or marked decrease in SNT and STG-posi tive nerve fibres in the smooth-muscle layers and in hypertrophic nerv e trunks. Our data indicate that important proteins necessary for the docking of synaptic vesicles at the presynaptic plasma membrane are lo st in fibres innervating the smooth muscle of HD and suggest that abno rmal neurotransmission may have a. role in the maintenance of muscle s pasticity.