Immunohistochemical distribution of some regulatory peptides in the rat stomach

Abstract EN

The innervation of the rat stomach has been re-analyzed using immunohistochemical localization of cholinergic markers.

These include the common type of choline acetyltransferase (cChAT) and the peripheral type (pChAT), which is the product of a splice variant of ChAT mRNA and preferentially localized to peripheral cholinergic nerves.

In addition we studied the immunolocalization of vesicular acetylcholine transporter (VAChT), neuronal nitric oxide synthase (nNOS) and tyrosine hydroxylase (TH).

Paraffin embedded tangential sections from the rat stomach were used to demonstrate the immunolocalization of cholinergic and nitrergic neurons and nerve fibers in the rat stomach using antibodies to pChAT, cChAT, VAChT and nNOS.

A ganglionated submucosal plexus (SP) was almost absent from the gastric wall, apart from some scattered neurons.

Most myenteric plexuses (MP) in the rat stomach showed positive immunostaining for pChAT, cChAT and nNOS only, whereas VAChTand TH-immunoreactivities (IR) were observed in the form of varicose nerve fibers and nerve terminals in the rat gastric wall.

These results indicate that in the rat gastric wall, submucosal and myenteric nerve fibers showed heterogeneous staining with regard to the examined regulatory peptides and transmitters.

The submucosal neurons were almost absent, while the myenteric neurons showed only pChAT, cChAT and nNOS immunostaining suggesting morphological evidence for the roles of cholinergic, nitrergic and adrenergic mechanisms in stomach secretory and motor functions.