gastrin-releasing-peptide and Hypertrophy

The distributions of nerve cells and fibers with immunoreactivity for the peptides enkephalin, gastrin-releasing peptide, neuropeptide Y, somatostatin, substance P, and vasoactive intestinal peptide were examined in specimens of myenteric plexus and external muscle from the pylorus of 20 infants with hypertrophic pyloric stenosis. These were compared with peptide distributions in pyloric samples from unaffected infants and adults. In the normal pylorus the circular muscle was richly supplied with fibers reactive for enkephalin, neuropeptide Y, substance P, and vasoactive intestinal peptide. In pyloric stenosis, these immunoreactive fiber bundles were either missing or less than 5% of normal. In contrast, there were reactive cell bodies and nerve fibers in the myenteric plexuses of both normal and affected specimens. In the samples from cases of stenosis, swollen nerve fibers that appeared to be in the process of degeneration were frequently encountered. It is concluded that infantile hypertrophic pyloric stenosis is associated with a loss of peptide immunoreactivity in nerve fibers in the circular muscle, although the same peptides are still revealed in fibers and in nerve cell bodies in the myenteric plexus.

Topics: Enkephalin, Leucine; Female; Gastrin-Releasing Peptide; Humans; Hypertrophy; Infant; Male; Myenteric Plexus; Nerve Fibers; Neuropeptide Y; Peptides; Pyloric Stenosis; Pylorus; Somatostatin; Substance P; Vasoactive Intestinal Peptide

The gastrointestinal tract harbors several populations of peptide containing nerve fibers. Among the gut neuropeptides are vasoactive intestinal peptide (VIP), substance P, enkephalin, and gastrin releasing peptide (GRP). We have examined specimens from five patients with pyloric stenosis and from five controls immunocytochemically with respect to the density of nerve fibers containing VIP, substance P, enkephalin, or GRP. In the control specimens VIP and enkephalin fibers were fairly numerous, whereas substance P and GRP fibers were few. In the pyloric stenosis patients the density of VIP fibers and enkephalin fibers was reduced in the smooth muscle. In the myenteric ganglia there was no such reduction. Substance P and GRP fibers were rare as in controls. The results indicate a reduction of VIP and enkephalin fibers in smooth muscle in pyloric stenosis patients and may be interpreted to support the view that an impaired neuronal function is involved in the pathophysiology of pyloric stenosis.

Topics: Enkephalins; Female; Fluorescent Antibody Technique; Gastrin-Releasing Peptide; Gastrins; Humans; Hypertrophy; Infant; Infant, Newborn; Male; Muscle, Smooth; Nerve Fibers; Peptides; Pyloric Stenosis; Substance P; Vasoactive Intestinal Peptide