METALLOTHIONEIN EXPRESSION DURING LIVER-REGENERATION AFTER PARTIAL-HEPATECTOMY IN CADMIUM-PRETREATED RATS

Metallothionein is a low molecular mass protein inducible mainly by he avy metals, having high affinity for binding cadmium, zinc and copper. In the present study we investigated the expression of metallothionei n in regenerating liver, at different time intervals, in cadmium pretr eated partially hepatectomized rats. Liver metallothionein is highly e xpressed during regeneration induced by partial hepatectomy in rats, p roviding zinc within the rapidly growing tissue. Cadmium pretreatment caused inhibition of the first peak of liver regeneration, while metal lothionein expression was markedly more prominent in the liver residue s of cadmium-pretreated rats. These resuits demonstrate that although metallothionein able to bind temporarily metal ions as zinc and cadmiu m has been highly expressed, the liver regenerative process was inhibi ted possibly due to the effects of cadmium on other pivotal events nec essary to the DNA replication.