Adult-onset methylmercury (MeHg) exposure is thought to result primarily in sensory and motor deficits but effects on learning are poorly understood. One mechanism by which chronic MeHg may exert its neurotoxicity is via sustained disruption of intracellular calcium homeostasis, with a consequent increase of intracellular Ca(2+) ions in vulnerable neurons. A biochemically heterogeneous group of...

Methylmercury (MeHg) is a persistent environmental pollutant whose adverse effects on the human health manifest as impairments to the nervous system. The molecular basis of the damage caused is not yet understood but preliminary experimental data from rat neural stem cells studies suggest that some toxic effects arise through the interference of MeHg with the activity of the ligand-dependent gl...

INTRODUCTION Exposure to methylmercury (MeHg) before birth can adversely affect children's neurodevelopment. The most common form of prenatal exposure is maternal fish consumption, but whether such exposure harms the fetus is unknown. We aimed to identify adverse neurodevelopmental effects in a fish-consuming population. METHODS We investigated 779 mother-infant pairs residing in the Republic...

With seasonal wetting and drying, and high biological productivity, agricultural wetlands (rice paddies) may enhance the conversion of inorganic mercury (Hg(II)) to methylmercury (MeHg), the more toxic, organic form that biomagnifies through food webs. Yet, the net balance of MeHg sources and sinks in seasonal wetland environments is poorly understood because it requires an annual, integrated a...

A series of severe droughts during the course of a long-term, atmospheric sulfate-deposition experiment in a boreal peatland in northern Minnesota created a unique opportunity to study how methylmercury (MeHg) production responds to drying and rewetting events in peatlands under variable levels of sulfate loading. Peat oxidation during extended dry periods mobilized sulfate, MeHg, and total mer...

The effects of methylmercury (MeHg) on components of the cholinergic system were evaluated in captive mink (Mustela vison). Cholinergic parameters were measured in brain regions (occipital cortex, cerebellum, brain stem, basal ganglia) and blood (whole blood, plasma, serum) following an 89 d exposure to MeHg at dietary concentrations of 0, 0.1, 0.5, 1, and 2 ppm (n = 12 animals per treatment). ...

The physical factors controlling total mercury (HgT) and methylmercury (MeHg) concentrations in lakes and streams of northeastern USA were assessed in a regional data set containing 693 HgT and 385 corresponding MeHg concentrations in surface waters. Multiple regression models using watershed characteristics and climatic variables explained 38% or less of the variance in HgT and MeHg. Land cove...

The use of phytochemicals has been widely used as inexpensive approach for prevention of diseases related to oxidative damage due to its antioxidant properties. One of dietary flavonoids is chrysin (CR), found mainly in passion fruit, honey, and propolis. Methylmercury (MeHg) is a toxic metal whose main toxic mechanism is oxidative damage. Thus, the study aimed to evaluate the antioxidant effec...

Zinc (Zn), aluminium (Al), mercury (Hg), methylmercury (MeHg) and lead (Pb) extracellulary applied reduce voltage-activated calcium channel currents (VACCCs); Pb and Al also reduce N-methyl-D-aspartate (NMDA)-activated channel currents (NACCs). Pb is most effective in reducing VACCCs, with an IC50 of 0.46 microM, followed by Hg (IC50 = 1.1 microM) and MeHg (IC50 = 2.6 microM). Zn and Al were le...

Methylmercury (MeHg) mediated cytotoxicity is associated with loss of intracellular calcium (Ca²⁺) homeostasis. The imbalance in Ca²⁺ physiology is believed to be associated with dysregulation of Ca²⁺ intracellular stores and/or increased permeability of the biomembranes to this ion. In this paper we summarize the contribution of glutamate dyshomeostasis in intracellular Ca²⁺ overload and highl...