Organic anion transporter 1 (OAT1) is a mechanism for uptake of mercuric-cyanide complexes into proximal tubular cells.

The processing of gold ore with both mercury (Hg) and cyanide (-CN) leads to widespread environmental contamination. Hg and its related compounds form complexes with -CN in the environment, which may result in human exposure through ingestion of contaminated food or water. The kidney is a significant site of Hg accumulation, but the mechanisms by which mercuric cyanide (Hg(CN)n2-n) and methylmercuric cyanide (H3CHg(CN)n1-n) complexes are taken up by renal tubular cells are unknown. We hypothesized that the organic anion transporter (OAT1) is involved in the uptake of these complexes. To test this hypothesis, the time course, temperature-dependence, saturation kinetics, and substrate specificity of Hg uptake were examined in human embryonic kidney cells stably transfected with OAT1. Our data show that these complexes are taken into proximal tubular cells via OAT1. These data are the first to identify a mechanism involved in the uptake of mercuric-cyanide species into proximal tubular cells.