NADPH-d cells (mast cells) around and within the autonomic nerves of porcine renal hilus

The enzymehistochemical localization of nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) reactive cells next and within the autonomic nerves in the porcine kidney's hilus, close to renal artery and vein as well as in its adventitia, was studied. It was established that the prevailing part of NADPH-d-reactive cells were distributed next to and within NADPH-d-reactive autonomic fibers around the renal vein. Comparatively small number of reactive cells was found around the renal artery, but single NADPH-d-reactive cells were found in the neighbouring autonomic nerves as well. The cells observed next to nerves had much more expressed reaction (granules) than those, located in the nerves. Toluidine blue staining on frozen and paraffine sections from the same areas showed well-expressed γ-ma metachromasia in mast cells with similar or identical localization. This indicated that observed reactive cells were mast cells.The obtained data convincingly showed that porcine NADPH-d cells may produce nitric oxide and in this way most probably they were involved in the function of autonomic nerves in the renal blood vessels (vasodilatation) and the kidney function, as well.