The excitotoxic effect of NMDA on human lymphocyte immune function.

N-Methyl-d-aspartate (NMDA)-activated glutamate receptors are expressed in lymphocytes, but their roles have not yet been defined. We show that incubation of human peripheral blood lymphocytes with NMDA resulted in increased intracellular calcium and reactive oxygen species (ROS) levels through effects on NMDA-activated glutamate receptors. In terms of ROS production, T cells were most affected, followed by NK cells, whereas B cell ROS levels were not increased.

Erythrocyte and plasma protein modification in alcoholism: a possible role of acetaldehyde.

Analysis of the oxidative modification of plasma and erythrocyte ghost proteins of chronic alcoholic subjects and healthy non-alcoholics has been performed. It was found that increased levels of protein carbonyls in both plasma and erythrocyte ghosts from alcoholic subjects occurred in comparison to the levels found in preparations from non-alcoholics. Plasma proteins from alcoholic subjects did not show evidence of cross-linking, although plasma protein concentration and composition were changed.

Rodent lymphocytes express functionally active glutamate receptors.

RT-PCR demonstrated that ionotropic (iGluR NR1) and metabotropic (mGluR Group III) glutamate receptors are expressed in rodent lymphocytes. Flow cytometry showed that activation of iGluR NR1 by N-methyl-D-aspartate (NMDA) increased intracellular free calcium and reactive oxygen species (ROS) levels and activated caspase-3. The latter effect was attenuated by the NMDA antagonist, 5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine (MK-801), by the antioxidant N-acetylcysteine and by cyclosporin A.