Significance of the neuropeptide ghrelin system in mecha-nisms of adaptation after experimental stress

The work is devoted to the analysis of indicators of the reactivity of the ghrelin system in the model of psychogenic stress. In recent years, it has been shown that the significance of the ghrelin system of the brain is not limited to the regulation of energy balance and eating behavior. It has been established that short-term stress experience is expressed by erosive inflammation of the mucous membrane, the death of many mucous cells, as well as an increase in the degree of mucoid cell differentiation of exocrinocytes. Along with other peptide regulatory systems, it plays an important role in the mechanisms of stress, reinforcement and addiction. Therefore, it is advisable to consider the elements of this system, first of all, as molecular targets of pharmacological action in order to correct the states of addiction and post-stress disorders. Using histological, immunohistochemical and morphometric methods, reactive changes in ghrelin-producing endocrinocytes of the stomach and hypothalamus, as well as elements of the inner part of the gastric mucosa, were established in the model of psychogenic stress and after replacement therapy. The short-term experience of psychogenic stress in the experimental model is expressed by persistent degenerative changes in GPEC (ghrelin-producing endocrine cells), erosive inflammation of the gastric mucosa, the death of many mucous cells, and an increase in mucus production in viable epithelial cells. Neuropeptide regulatory systems (ghrelin, kisspeptins, orexins, dynorphin, and others) are increasingly involved in physiological and pharmacological experiments on modeling the development of an organism at different levels of its organization and a number of major functional disorders (memory, satiety, stress, addictions). The adaptive changes observed in the gastric mucosa after stress and ghrelin replacement therapy may be due to the modulating effect of ghrelin on corticoliberin-producing neurons. Meanwhile, information about their functional morphology is just beginning to accumulate.

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