In vivo chronic lead exposure alters [3H]nitrendipine binding in rat striatum

The effect of lead as a neurotoxic agent has been associated with alterations in calcium metabolism. On this line, the present study shows that lead alters the characteristics of [3H]nitrendipine ([ 3H]NDP) binding to rat striatal membranes. In vitro, lead shares the action of calcium in enhancing [3H]NDP binding although it is more potent on a molar basis. In vivo, lead exposure through drinking water enhances [3H]NDP binding to crude synaptosomal membrane preparations. This effect is lost when membranes are washed with EDTA-EGTA, indicating that the increased binding is due to the persistence of lead in the brain of treated rats.