Pathway in rat brains under experimental obesity caused long-term progesterone administration

Abstract

Obesity is one of the most common complex health problem. The pathway of serotonin synthesis takes part in neuroendocrine regulation, as well as in the regulation of a number of behavioral functions of the body and fat deposition. Serotonin is a mediator of the amine nature, which functions as a neurotransmitter and tissue hormone. The greatest amount of serotonin is synthesized in the brain and 12 duodenum. As a neurotransmitter, serotonin affects both directly and indirectly on the function of most brain cells. Female hormone progesterone influence on serotonin functions. One of the effect of progesterone is increasing of amount of fat tissue during the pregnancy. Long-term using of progesterone in hormone substitution therapy or as part of contraception also lead to fat accumulation effect. The levels of activity of serotonergic system enzymes, tryptophan hydroxylase, tryptophan decarboxylase and monoamine oxidase (MAO), and tryptophan, 5-hydroxytryptophan, serotonin and 5-hydroxyindoleacetic acid concentrations in the rat brain under obesity conditions caused by prolonged administration of progesterone were determined in this study. Studies have shown that the content of tryptophan, 5-hydroxytryptophan, serotonin and 5-hydroxyindoleacetic acid in the brain of rats under obesity caused by prolonged administration of progesterone increased in comparison with the rats of the control group. The levels of tryptophan hydroxylase and MAO activity decreased, and tryptophan decarboxylase activity levels increased in the rat brain under obesity conditions caused by prolonged administration of progesterone. Thus, as a result of our studies, we found an imbalance in the system of serotonin metabolism in the brain of rats with the development of hormonal obesity induced by prolonged administration of progesterone, which may indicate the involvement of the serotonergic neurotransmitter system in the mechanisms of the development of obesity and concomitant diseases.