Toxic effects of metals:: modulation of intracellular calcium homeostasis

Metals and metalloids with their organic derivatives are part of the environment occurring naturally or being introduced upon human activity (e.g. industry, agriculture or medicine). Even if they are useful for humans, these chemicals could be highly toxic (e.g. mercury, lead, arsenic, tin) acting as neurotoxins or carcinogens. Several human cases of metal derived intoxication have been documented resulting in health complications or ending with death. The mechanisms of toxicity are not well understood. Since calcium is a universal second messenger in all cell types it is a good candidate to investigate how changes in the intracellular calcium homeostasis are involved in metal(loid) toxicity. In this mini-overview the interaction of metallic species with channel proteins at the outer cell membrane, as well as with calcium release sides from the calcium stores and the impairment with calcium extrusion mechanism is discussed.