STUDY OF INTERACTION BETWEEN L-GLUTAMATE AND HUMAN BLOOD-LYMPHOCYTES

The presence of specific glutamate receptors on T lypmphocytes separat ed from normal human blood was investigated. Upon study of T lymphocyt es interaction with [H-3]glutamate the last one was found: to bind spe cifically to these cells, K-d= 2.36 x 10(-7) M. Thirteen unlabelled co mpounds were tested as potential glutamate competitors. II was shown t hat only quisqualate (a structural analogue of glutamate) and dipeptid es Ala-Glu, Glu-Ala, Glu-Glu competited with [H-3]glutamate in binding to a common binding site. The experiments on binding of labelled and unlabelled glutamate bulky conjugates with dextran have demonstrated t hat both conjugated and free glutamate interacted with the common bind ing sites on the outer cell membrane. By this means it was shown that T lymphocytes exposed quisqualate-sensitive glutamate receptors on the outer surface of the plasma membrane. (C) 1997 Elsevier Science B.V.