Effects of Sub-toxic Heavy Metals on Dopamine Transporter Function

Abstract

The results from the LDH assays determined there was a significant effect of time, concentration, and time X concentration interaction on cell viability when SK-N-SH cells were treated for 24-96 hours with HgCl2 (0.1-50M) or MnCl2 (1-10 M). Caspase-3/7 activity and [3H]GBR-12,935 binding was not different in either the HgCl2 or MnCl2 groups compared to controls. [3H]GBR-12,935 saturation curves revealed there was no difference in Bmax or KD values following 48 or 96 hour HgCl2 or MnCl2 exposure. However, a trend for increased Bmax after 48 hour HgCl2 exposure was observed. [3H]DA uptake assays determined there was a significant difference between HgCl2 (decreased uptake) and MnCl2 (increased uptake) compared to controls after 48 hours. Uptake values were not different between treatment and controls at 96 hours. From these studies, it is concluded that DAT functionality is affected by 1.0M HgCl2 or 10.0M MnCl2 treatment in SK-N-SH cells.