Neurosteroid correlates of emotional behavior in alcohol dependence

Abstract

The aim of the study was to determine neurosteroid correlates of emotional behavior of animals under conditions of alcohol dependence. Ethological testing made it possible to identify rats with basic different types of emotional behavior in the general pool of animals: zoocentric, dominant or submissive and to track their change under the influence of prolonged (30 days) alcoholization with 15 % ethanol solution. It was found that hypothalamic testosterone, hippocampal progesterone and amygdala dehydroepiandrosterone are associated with the basic emotional behavior of animals. Chronic alcoholism caused a decrease in the concentration of sex steroids (testosterone and estradiol), dehydroepiandrosterone and cortisol in the hypothalamus and an increase in the content of progesterone in it; a decrease in the level of all studied neurosteroids in the hippocampus, while in the amygdala these indicators increased (with the exception of dehydroepiandrosterone). It was shown that the basic emotional behavior of rats that chose water in the two-bottle test was significantly different from that of rats that preferred ethanol solution: first of all, this was related to animals with dominant and submissive behavior, in which the level of testosterone in the hypothalamus increased significantly, in contrast to zoocentric rats. The individual dose of ethanol consumed in animals that chose water in the two-bottle test was almost two times less than the individual dose in rats that preferred ethanol solution, which was associated with cortisol levels in the hippocampus and hypothalamus of the brain of animals after 30 days alcoholization. Consequently, long-term alcohol consumption led to the involvement of a pool of neurohormones (hypothalamic progesterone, dehydroepiandrosterone, estradiol, and cortisol; hippocampal testosterone and amygdala progesterone, dehydroepiandrosterone, and cortisol) to regulate emotional behavior. In addition, neuroactive steroids of the peripheral circulation, such as the sex hormones testosterone and estradiol and progesterone, also had a certain effect.