摘要
The mechanism of action of cadmium in the inductive pathway of metallothionein (MT) synthesis was studied in the rat. Cadmium significantly elevated the MT leve by 872% which was antagonised by coadministration of either verapamil (343.5%) or innophore (570%). The Ca-dependent biomolecules such as cyclic AMP or calmodulin remained depressed in all treatment regimens except calmodulin in the ionophore treated rat. Total Ca2+ showed no increase in its profile except in the ionophore treatments either alone or with CdCl2. The Na+ profile is, however, significantly elevated in all cases except the ionophore treated rat. The present study clearly indicates that (a) Ca2+ has no first messenger role in the schematic events leading to MT synthtsis and (b) Na+ may be regarded as a possible candidate in the molecular events of Cd-induced MT synthesis
The mechanism of action of cadmium in the inductive pathway of metallothionein (MT) synthesis was studied in the rat. Cadmium significantly elevated the MT leve by 872% which was antagonised by coadministration of either verapamil (343.5%) or innophore (570%). The Ca-dependent biomolecules such as cyclic AMP or calmodulin remained depressed in all treatment regimens except calmodulin in the ionophore treated rat. Total Ca2+ showed no increase in its profile except in the ionophore treatments either alone or with CdCl2. The Na+ profile is, however, significantly elevated in all cases except the ionophore treated rat. The present study clearly indicates that (a) Ca2+ has no first messenger role in the schematic events leading to MT synthtsis and (b) Na+ may be regarded as a possible candidate in the molecular events of Cd-induced MT synthesis
