[Spatial organization and morphometric characteristic of histaminergic neurons of the rat brain].

The aim of the study was the estimation of the spatial organization, the density of distribution, number, sizes and shape of histaminergic neurons of the rat hypothalamus. The investigation was carried out in 50 adult Wistar rats, using the methods of histochemistry, morphometry, computer image analysis and 3D reconstruction of hypothalamic histaminergic nuclei. It was found that the total bilateral volume of rat brain histaminergic nuclei was equal to 0.5 mm3 : E2 nucleus occupied 40% of their total volume, while E4 occupied 35%, E3 - 13%, E5 - 9% and E1 - 3%. The density of distribution of monoamineoxidase B-positive neurons was decreased in a series E1 > E3 > E2 (compact nuclei) > E4 (intermediate nucleus) > E5 (diffuse part). The average number of histaminergic neurons in rat hypothalamus was equal to (372 +/- 28) x 10(2): E2 nucleus contained 54% of that amount, E3 - 23%, E4 - 16%, E1 - 7%, E5 - 0.32%. In E1-E3 nuclei, small and medium neurons round in shape were prevalent, while in E5 these were medium and large neurons of fusiform shape. The subpopulation of giant histaminergic neurons was found in E4-E5.