Biochemical and histopathological alterations in kidney of rats chronically exposed to mild silver protein

Chronic administration to Wistar rats of Mild Silver Protein (MSP) to a dose of 222 mg Ag/kg/day in the drinking water for six months showed that the MSP produces argyria, with histopathological lesions in the kidney, the organ where silver accumulates. The histopathology of the kidney showed capillary damage, with alteration of the vascular wall, increased perivascular cellularity and area with focal haemorrhage. The studies in 'open field' were carried out after one, three and six months of treatment and did not show modifications in the pattern of spontaneous locomotor activity. Parameters such as uremia, creatininemia, phosphatemia, alkaline phosphatase, aspartate aminotransferase, alanino–aminotransferase, gamma–glutamyl transpeptidase and lactate dehydrogenase registered in plasma displayed normal values showing normal renal and hepatic functionality. The present results encourage the need for future research to elucidate the molecular pathophysiology and potential functional alterations sustained by the morphological changes found.

Keywords: MSP exposure, mild silver protein, oral chronic silver toxicity, kidney alteration, biochemical alterations, histopathological alterations, capillary damage