Patterns of expression of TRPM7, the major cellular magnesium transporters in neurons of the hypothalamic region and hippocampus, were studied immunohistochemically. Multidirectional nature and different levels of the expression of the above antigen were revealed during modeled magnesium deficiency with regard to structural and functional features of neuron organization in the hypothalamic paraventricular and supraoptic nuclei as well as hippocampal field CA1 and CA3. Changes in the structural characteristics of neurons in the studied areas (absolute and relative indicators) and TRPM7 expression patterns were quantitatively analyzed considering the data on the role of the studied antigen in magnesium homeostasis, cell damage, and compensation.