GABA MODULATES CYTOTOXICITY OF IMMUNOCOMPETENT CELLS EXPRESSING GABA(A) RECEPTOR SUBUNITS

C57 black mouse splenic T lymphocytes effector cells were co-cultivate d with Balb/c mouse splenic cells for sensitization; P815 DBA mouse ma stocytoma target cells were then added and specific T cell-dependent c ytotoxicity determined. This cytotoxicity increased after gamma-aminob utyric acid (GABA) treatment of the sensitized effecters, hut decrease d after GABA treatment of the targets. These GABA effects seemed to be specific since they were partially mimicked by linear but not ramifie d GABA analogues. Furthermore, they were likely mediated by GABA(A) re ceptor since GABA(A) receptor subunit mRNAs and protein could be demon strated in effector or target immune specific cells, suggesting that u nder yet to be defined circumstances, GABA may affect T cell functions . (C) 1998 Elsevier, Paris.