The effects of methylmercury on endogenous dopamine efflux from mouse striatal slices

• Published in: Toxicology letters Vol. 89; no. 1; pp. 43 - 49
• Main Authors: Kalisch, Bettina E., Racz, William J.
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 01-12-1996; Amsterdam Elsevier Science
• Subjects: Animals; Biological and medical sciences; Calcium-Transporting ATPases - drug effects; Calcium-Transporting ATPases - metabolism; Chemical and industrial products toxicology. Toxic occupational diseases; Corpus Striatum - drug effects; Corpus Striatum - metabolism; Dopamine; Dopamine - metabolism; Dose-Response Relationship, Drug; Efflux; H(+)-K(+)-Exchanging ATPase - drug effects; H(+)-K(+)-Exchanging ATPase - metabolism; In Vitro Techniques; Male; Medical sciences; Methylmercury; Methylmercury Compounds - toxicity; Mice; Striatal slices; Toxicology; Various organic compounds; Efflux; Dopamine; Methylmercury; Striatal slices; Toxicity; Rodentia; Catecholamine; In vitro; Pollutant; Dopaminergic transmission; Vertebrata; Mammalia; Mouse; Animal; Central nervous system disease; Neurotransmitter; Mercury Organic compounds; Brain (vertebrata)
• ISSN: 0378-4274; 1879-3169
• DOI: 10.1016/S0378-4274(96)03787-3

The present study investigated the effects of in vitro methylmercury (MeHg) exposure on endogenous dopamine (DA) efflux from mouse striatal slices. MeHg produced a concentration-dependent increase in the spontaneous efflux of DA which was independent of the availability of Ca
2+ in the superfusion medium. The Ca
2+-dependent K
+-evoked release of DA was significantly enhanced by 50 and 100 μM MeHg. This increase could not be solely accounted for by the MeHg-induced increase in spontaneous DA efflux. The K
+-stimulated efflux of DA was enhanced by MeHg m both the presence and absence of Ca
2+in the superfusion medium, suggesting that under depolarizing conditions, DA efflux induced by MeHg has a Ca
2+-independent component. The alterations in DA efflux occurred at concentrations of MeHg previously found in the CNS of animals exhibiting symptoms of MeHg intoxication suggesting that alterations in DA neurotransmission in the striatum may contribute to the symptoms of MeHg toxicity.