MERCURY AND METHALLOTHIONEIN-LIKE PROTEINS IN THE PARTICULATE CELL FRACTION OF HUMAN CEREBELLAR NUCLEUS DENTATUS
I. Falnoga, M. Tušek-Žnidariè, R. Milaèiè Jožef Stefan Institute, Jamova 39, 1111 Ljubljana, Slovenia
The particulate fraction (pellet) of human cerebellar nucleus dentatus from a retired mercury mine worker with a high mercury and selenium content (2.35 ìg/g, 1.02 ìg/g) was subjected to mild extraction of Hg binding proteins with a buffer containing 10% mercaptoethanol (ME). The amount of mercury solubilised in this procedure was very low, about 3% of the pellet Hg content. Nevertheless, in the ME extract the presence of metallothionein-like proteins (MT-LP) were found by Sephadex G-75 gel chromatography and subsequent metal analysis. They were detected as Cu, Zn, Pb, Hg MT-LP, where the binding of Cu was much the highest and Hg was present only in traces. These data indicate that in accordance with literature discussions MT in nucleus dentatus could be involved in Cu metabolism and in short term heavy metal detoxification (Pb, Hg).