DISTRIBUTION OF PEPTIDE-CONTAINING NERVE-FIBERS IN ACHALASIA OF THE ESOPHAGUS

In this study the innervation of the normal human oesophagus was compa red with samples taken from 12 patients undergoing Heller's cardiomyot omy for achalasia. The distribution of all nerve fibres in the oesopha geal wall was subpopulations of nerve fibres were neuropeptide Y, enke phalin and substance P. In healthy oesophagus, many nerve fibres immun oreactive for vasoactive intestinal peptide and neuropeptide Y were pr esent in the circular and longitudinal muscle layers of the oesophagea l wall and in the cardia of the stomach, whereas fibres immunoreactive for enkephalin and substance P were uncommon. Neuropeptide Y-reactive Fibres were commonly seen around blood vessels. In the myenteric plex us cell bodies reactive for vasoactive intestinal peptide and neuropep tide Y were prevalent, as were varicose and non-varicose fibres. In co ntrast, samples from patients with achalasia revealed few nerve fibres immunoreaction for vasoactive intestinal peptide or neuropeptide Y in either circular or longitudinal muscle, suggesting damage to the inhi bitory motor neurons to the muscle layers. Very few fibres were found that were reactive for neuron-specific enolase, indicating that other fibre populations (e.g. excitatory cholinergic motor neurons) are also damaged in achalasia. These abnormalities were observed in biopsies f rom both tile constricted and dilated portions of the oesophagus, but the pattern of innervation in the gastric cardia was normal. Myenteric ganglion cells were seen in the oesophagus in only two patients and v aricose nerve fibres in the myenteric plexus were uncommon. Neuropepti de Y-reactive perivascular nerve fibres were still found in achalasia as well as non-varicose nerve fibres in the myenteric plexus. These fi ndings indicate damage to all intrinsic neurons in the oesophageal wal l in achalasia; however, extrinsic nerve fibres appear to be intact.