312 Neuroscience Letters, 93 (1988) 312--317 Elsevier ScientificPublishers Ireland Ltd. NSL 05635 Effect of antemortem and postmortem factors on [3H]glutamate binding in the human brain Johannes Kornhuber, Wolfgang Retz, Peter Riederer, Helmut Heinsen and Jiirgen Fritze Department of Psychiatry, Clinical Neurochemistry. University of Wiirzburg ( F.R.G. ) (Received 22 April 1988; Revised version received 28 June 1988;Accepted 2 July 1988) Key words: [3H]Glutamate binding; Receptor; Postmortem human brain; Age; Development;Glutamate; N-Methyl-D-aspartate (NMDA) The effect of a number of antemortem and postmortem factors on both N-methyl-o-aspartate (NMDA) sensitive and NMDA insensitive[3H]glutamatebinding was investigated in the frontal cortex and putamen of human brains. There was a high correlation between both binding sites (r=0.86, P<0.001) and both binding sites increased during the early postnatal period reaching a maximum between age 1 and 2 years. After age 10 years NMDA sensitive sites disappeared at 9.2% per decade while the NMDA insensitive sites disappeared at 7.4% per decade only. Therefore, the ratio between NMDA sensitive and NMDA in- sensitive sites changed in favor of the NMDA insensitive site with increasing age. The storage time of brain tissue had a strong reducing effect on both binding sites, again affecting the NMDA sensitive sites more severely. There was no obvious effect of gender, brain weight or postmortem time interval on either binding site. Furthermore, there was no differencebetween frontal cortex and putamen. Both binding sites were bilateral symmetrically distributed in either frontal cortex and putamen. A substantial portion of central mammalian neurons use glutamate as an excita- tory neurotransmitter and a variety of disease states has been associated with an im- pairment of the glutamatergic neurotransmission. Therefore, measurement of gluta- mate receptors has been performed by several groups in postmortem human brains using [3H]glutamate as the ligand [24]. However, problems may arise from the unavoidable delays in processing the tissue for dissection and the necessity for pro- longed storage prior to analysis. The aim of the present investigation was, therefore, to evaluate the effects of age, gender, brain weight, laterality, postmortem interval (time between death and freezing of tissue) and storage time of brain tissue on [3H]glutamate binding in the frontal cortex and putamen of human brains. Tissue was taken at autopsy from subjects with no history of neurological or psy- chiatric disorder (causes of death included sudden infant death syndrome, trauma Correspondence." J. Kornhuber, Klinische Neurochemie, Psychiatrische Klinik der Universit/it Wfirzburg, Ffichsleinstrasse 15, 8700 Wiirzburg, F.R.G. 0304-3940/88/$ 03.50 © 1988 Elsevier ScientificPublishers Ireland Ltd.