Immunohistochemical and electron-microscopic identification of neuroendocrine cells in the stomach of uremic rats.

Many disturbances in electrolyte and hormonal balance in the body induced by functional impairment of renal parenchyma may affect the activity of amine precursor uptake and decarboxylation (APUD) cells, which constitute a very important link in the regulation of homeostasis. The aim of the present study was the morphological, immunohistochemical and ultrastructural estimation of enteroendocrine cells in the stomach of uremic rats. Fragments of gastric pylorus were collected 1, 2 and 4 weeks after nephrectomy. Paraffin embedded sections were stained with H + E and by silver impregnation. For identification of neuroendocrine cells, immunohistochemical reactions were performed using specific antibodies against somatostatin, synaptophysin, neuron-specific enolase and anti-calcitonin gene related peptide. The analysis showed an increased number of APUD cells in the stomach of uremic rats compared to control rats, which may be a morphological expression of their hyperfunction in the functional impairment of renal parenchyma. These results suggest that chronic renal failure can modulate the secretory processes of APUD cells.