Renal handling of inorganic mercury in mice. The early excretion phase following a single intravenous injection of mercuric chloride studied by the Silver Amplification method.

The early renal excretion of mercuric mercury was studied in male BALB/c mice between 15 seconds and 30 min following a single intravenous injection of 3 mg HgCl2/kg body weight. The cytochemical Silver Amplification method applied at the light and electron microscopical levels showed mercury to be excreted by glomerular filtration and reabsorbed by proximal tubular epithelial cells by means of adsorptive endocytosis. Mercury was rapidly demonstrated in the lysosomal vacuome of proximal tubular epithelial cells. No uptake was observed from the peritubular side, and there was no evidence of tubular secretion of mercury. It is proposed that mercury is excreted in the form of mercury-protein complexes, assisted by the physiological proteinuria in mice, which is enhanced by mercury-induced damage to the glomerular structures.