Effect of polidan on ultrastructural changes in the cerebral cortex and hippocampus of rats.

Electron microscopy and morphometry of neurons in layer V of the somatosensory area in the neocortex and CA3 field in the dorsal hippocampus showed that single and 5-fold intraperitoneal injection of Polidan was followed by ultrastructural and metabolic changes in neurons reflecting activation of protein synthesis. The number of free ribosomes decreased; the number of polysomes and count of ribosomes in polysomes and tubules of the granular endoplasmic reticulum increased. Study of mitochondria and neuropil showed that Polidan activates synthetic processes in the neocortex and hippocampus. It should be emphasized that single treatment with Polidan led to functional activation of synthetic processes, while 5-fold injection of Polidan was followed by hyperactivation of synthetic processes and depletion of ultrastructures in the neocortex and hippocampus.

Morphofunctional changes in neurons of hippocampal fields and neocortical layers in rats treated with Polydan.

Light microscopy revealed four types of neurons differing by staining intensity and size in each of the pyramidal neuron populations in the dorsal hippocampal fields and layer V of the neocortical somatosensory area and in granular cells of the dentate fascia and stellate cells of layer II of the same cerebrocortical area in rats. Treatment with Polydan according to different protocols led to redistribution of these types of cells, which attests to stimulation of synthetic processes in these brain areas, rather than to similar sequence of the involvement of different brain areas in this process. Polydan promoted the increase in the mean number of nucleoli in the nuclei of neurons of all types, the degree of this increase being different for each type. It seems that morphological signs (staining intensity and number and size of nucleoli in the nuclei) reflect certain functional states of the neurons in the homogeneous populations. Presumably, various factors can stimulate transition of neurons from one morphofunctional status into another.