EN
The aim of the study was to determine the existence and co-existence patterns of VIP and NPY in neurons and nerve fibers of porcine lumbar-sacral sympathetic chain ganglia. The studied ganglia were fixed with 4% buffered paraformaldehyde (perfusion) and then labeled by means of double-immunofluorescence using a mixture of antibodies cultivated in different species. The highest number of NPY-positive cells was observed in the lumbar ganglia and diminished in the direction of the caudal, where only single neurons were observed. In contrast, a different pattern of distribution was observed for VIP-positive neurons, whose number was higher in the more caudally located ganglia. Two populations of VIP-positive neurons could be distinguished: single, showing strong immunofluorescence and often with visible processes, located in the central part of the ganglia and a second population, composed of clusters of 4-8 cells and often co-localizing NPY. VIP-positive nerve fibers surrounded both NPY+ neurons and neurons lacking either NPY and/or VIP. The presence of a small number of NPY-positive neurons exhibiting very weak immunofluorescence in more caudally located SChG could suggest a "switch" of neuromediators produced there. An increase in the percentage of non-noradrenergic sympathetic neurons in more caudally located SChG may thus be implicative for a specific innervation pattern of target tissues of these ganglia.