Manganese interactions with dopaminergic system.

Manganese is a trace element with important involvement in the central nervous system functioning. The effects of manganese excess on central dopaminergic system in case of both basal nuclei and reward system are linked to important pathologic states such as Parkinsonism and cognitive impairment. Our data show that Mn2+ reduces the intensity of experimental morphine addiction in rats (manganese chloride unequally decreases several symptoms of opioid withdrawal syndrome - signs such as compulsive mastication, grooming and teeth chattering being particularly affected). Manganese chloride, administered during conditioning acquisition phase in rats, significantly reduces the intensity of morphine conditioned place preference. We believe that manganese interaction with dopaminergic circuits in the brain reward system represents one of the most important aspects of the action of bivalent cations at central nervous system level.