Structural Organization and Interaction of Intrapancreatic Ganglia with the Myenteric Nerve Plexus of the Duodenum at the Early Stages of Postnatal Ontogeny in Rats

Studies using immunohistochemical markers – synaptophysin (SP), protein gene product 9.5 (PGP 9.5), and tyrosine hydroxylase (TH) – addressed the innervation of the pancreas and the myenteric nerve plexus of the duodenum (duodenum) in neonatal rats (n = 4) and demonstrated a tight link between the nerve plexuses in these organs. Some elements of the myenteric plexus penetrate the pancreas from the walls of the duodenum. Morphological and biochemical similarity was demonstrated between microganglia in the myenteric plexus of the duodenum and pancreas. Most differentiated neurons and bundles of axons in both plexuses were part of the parasympathetic compartment of the autonomic nervous system. There were no catecholaminergic neurons in the pancreas, and bundles of sympathetic fibers entering the organ from outside were few in number and were involved mainly in innervating blood vessels. This is the first report of the use of immunohistochemical reactions for PGP 9.5, SP, and TH to detect two types of nerve fibers in ganglia in the pancreas whose varicose terminals form cholinergic and catecholaminergic synapses around nerve cell bodies. © 2017, Springer Science+Business Media, LLC.