Light microscopic identification of vagal nerve innervation of the rat stomach using methylene blue.

Using a methylene blue staining techique, the innervation in the rat stomach has been studied. Several distinctive patterns of beaded and unbeaded nerves were seen. Axons in the muscle coat gave branches which ramified in connective tissue and were occasionally related to blood vessels. Further nerve fibres passed directly between the muscularis mucosae and muscle coat whilst others ran between the epithelium and muscularis mucosae. A few fine terminal axons were observed close to cells throughout the epithelial layer. This method of identifying nerves will be useful in studying the consequences of vagal denervation and reinnervation following vagotomy in man and animals.