[PROSPECTS OF THE NUCLEAR PROTEIN NeuN APPLICATION AS AN INDEX OF FUNCTIONAL STATE OF THE VERTEBRATE NERVE CELLS].

Assessment of safety, viability, and functional state of nerve cells is the major problem in studies of experimental effects on various structures of vertebrate brain and in search for correlation between structural abnormalities and changes in physiological parameters. Such an assessment is possible with applying an immunocytochemical reaction to neuronal nuclear antigen NeuN discovered in 1992. Numerous studies of the protein showed its neural specificity and its amino acid consequence was found to have high interspecies concervatism. This review summarizes and analyzes the available data about the function of the NeuN protein in nerve cells and the results of using this marker for assessment of functional state and viability of CNS neurons in experiments. Particular attention is paid to. the critical analysis of the basic data used for the conclusions on the properties and functions of NeuN. It is stated that there are no satisfactory explanation for lacking the constitutive expression of this marker in some neuronal populations of the mammalian brain and spinal cord. The analysis of our own and literature data presented in the review suggests the future prospects of NeuN labeling for investigation of nerve cell responses to damage including comparative interspecies studies. Key words: brain, neuron, immunocytochemistry, neuronal protein NeuN, vertebrates.