抄録
Localization of SP and VIP in normal, transitional and aganglionic colorectal segments of Hirschsprung's disease was examined by immunohistochemical electronmicroscopy. Following results were obtained. 1. SP- and VIP-immunoreactive nerve cells and nerve endings were observed within the intramural plexuses of the normal colonic segment. Immunoreactive nerve fibers were also oberved in the muscular layers, especially in the circular layer, and VIP-immunoreactive nerve endings showed neuromuscular junction-like structures in the circular layer. 2. In the transitional segment SP-immunoreactive nerve cells and nerve fibers were found to disappear within the muscular layers, but VIP-immunoreactive nerve fibers were still observed there. 3. In the narrow segment neither SP・VIP-immunoreactive nerve cells nor fibers were observed in the muscular layers. Very few nerve fibers were found in the submucosal or subserosal layers and were considered to be originating from extraneous nerves. 4. In the lower recto-sigmoid narrow segment many SP・VIP-immunoreactive nerve fibers were observed in the muscular layers, but no neuromuscular connection-like structure was found there. These results suggested that SP- and VIP-mediated intrinsic neurons have some participations in the normal colonic movements and their absence in the narrow segment was supposed to contribute to causation of aperistalsis and narrowing there. In the lower recto-sigmoid aganglionic segment many extraneous SP・VIP-immunoreactive nerve fibers were observed, but no apparent neuromuscular connection-like structure was found there.
