DISTRIBUTION OF ENTERIC NEURONS SHOWING IMMUNOREACTIVITY FOR SUBSTANCE-P IN THE GUINEA-PIG ILEUM

Abstract

Substance P-like immunoreactivity has been localized in whole mount preparations of the isolated layers of the guinea-pig ileum. Axons containing substance P formed dense networks around the nerve cells and ran in the primary, secondary and tertiary nerve bundles of the myenteric plexus. 3.6% of the nerve cell bodies of the myenteric plexus and 11.3% of the cell bodies in the submucous plexus showed immunoreactivity for substance P. Axons ran in fine nerve bundles parallel to the longitudinal muscle, between this muscle and the myenteric plexus. Axons containing substance P also ran in small nerve trunks parallel to the circular muscle throughout its thickness and in the deep muscular plexus..