Decrease of catecholamine and neuropeptide Y-like immunoreactivity in the glycerol-induced acute renal failure of rats

Abstract

Changes of catecholamine and neuropeptide Y (NPY) were investigated in experimental acute renal failure (ARF) of rats. Concentrations of noradrenaline (NA) and dopamine (DA) were determined by chromatographic analysis using electrochemical detection. Renal content of NPY, identified by radioimmunoassay, was expressed as NPY-like immunoreactivity (NPY-LI). All animals with a plasma urea value higher than 200 mg/dl induced by injection of glycerol were employed as ARF subjects for the experiment. Formation of ARF was also confirmed by histological findings showing diffused necrosis of tubular epithelia. In ARF rats, renal contents of NA and DA decreased markedly (P less than 0.001), NA (ng/g wet tissue) decreased from 186.3 +/- 19.6 to 2.81 +/- 0.67 (n = 8), and DA (ng/g wet tissue) decreased from 14.69 +/- 4.97 to 4.05 +/- 2.66 (n = 8). Similarly, NPY-LI (pg/g wet tissue) in ARF was reduced significantly (P less than 0.001) from 435.23 +/- 35.82 to 4.61 +/- 0.52 (n = 8). The decrease of NA in ARF was obtained parallel to the change of NPY-LI; degeneration of adrenergic nerve fibers was confirmed by immunohistochemical observation. Results obtained suggest damage to the adrenergic and the dopaminergic innervation in the kidneys during ARF.