IMMUNOHISTOCHEMICAL COLOCALIZATION OF MET(5)-ENKEPHALIN-ARG(6)-GLY(7)-LEU8 WITH TYROSINE-HYDROXYLASE IN NEURONS OF THE PORCINE INFERIOR MESENTERIC AND CELIAC-SUPERIOR MESENTERIC GANGLIA

The localization and distribution of the proenkephalin A-derived octap eptide Met(5)-enkephalin-Arg(6)-Gly(7)-Leu(8) (MEAGL) was studied in t he porcine sympathetic prevertebral ganglia by using the indirect immu nofluorescence technique. In the inferior mesenteric ganglion, a small population of principal neurons and SIF cells contained intense MEAGL immunoreactivity. A very dense plexus of MEAGL-immunoreactive nerve f ibers was distributed in different parts of the ganglion. A low number of MEAGL- immunoreactive principal ganglion cells and SIF cells, as w ell as numerous nerve fibers were also present in the coeliac-superior mesenteric ganglion. Double staining experiments indicated that the M EAGL-immunoreactive principal neurons in the inferior mesenteric and c oeliac-superior mesenteric ganglia also contained tyrosine hydroxylase immunoreactivity.