IMMUNOHISTOCHEMICAL LOCALIZATION OF NEUROPEPTIDES IN THE PORCINE THORACOLUMBAR PARAVERTEBRAL GANGLIA

The existence and distribution pattern of neuropeptide Y, Met5-enkepha lin-Arg6-Gly7-Leu8, vasoactive intestinal polypeptide, calcitonin gene -related peptide, substance P and bombesin/gastrin releasing peptide i n the neuronal elements of the thoracolumbar paravertebral ganglia (T4 -L6) were studied immunohistochemically in sexually immature female pi gs. Subpopulations of nerve cell bodies containing immunoreactivity to neuropeptide Y, Met5-enphalin-Arg6-Gly7-Leu8, vasoactive intestinal p olypeptide and calcitonin gene-related peptide were described. However , neurons were non-immunoreactive for substance P and bombesin/gastrin releasing peptide. The solitary small intensely fluorescent cells con tain calcitonin gene-related peptide-, substance P- and Met5-enkephali n-Arg6-Gly7-Leu8-, whereas the some cells in clusters contained only s ubstance P and Met5-enkephalin-Arg6-Gly7-Leu8. Immunoreactivities to a ll studied peptides occured in the nerve fibres within investigated ga nglia. Additionally the number of nerve fibres containing particular p eptides as well as their distribution pattern were found to vary. The results of this study were compared with those of previous investigati ons in other species.