EVALUATION OF THE EFFECTS OF CHRONIC ALCOHOL AND WITHDRAWAL ON IMMUNOREACTIVE SEROTONERGIC CELLS IN THE DORSAL RAPHE NUCLEUS IN FEMALE RATS
Alcohol; Withdrawal; Central Nervous System; Serotonin; Dorsal Raphe Nucleus; Emotional Disorders
Chronic alcohol use may cause adaptive changes in neural cells, modifying signal transmission and release of neurotransmitters, and impairing the normal functioning of the central nervous system. It has been observed that the serotonergic system is affected by the action of alcohol, being dysfunctional both during chronic use and alcohol withdrawal, which favours the development of emotional disorders, such as anxiety and depression. Women constitute a risk group for these emotional disorders, so that in this study it was evaluated whether chronic consumption and withdrawal of alcohol promoted changes in serotonergic cell density in the dorsal raphe nucleus of Wistar female rats. The animals were submitted to increasing concentrations of alcohol (2%, 4% and 6%) as the unique source of liquid diet for 21 days or water (control group). Both groups had free access to the food. For the withdrawal protocol, on the 21st day of consumption, alcohol was replaced with water and the animals were submitted to transcardiac perfusion and brain removal 72 hours after replacement by water (short-term withdrawal group) or 21 days after replacement by water (long-term withdrawal group). Immunohistochemical analysis for the detection of serotonin immunoreactive cells in the dorsal (DDR) and caudal (CDR) parts of the dorsal raphe nucleus showed that short- and long-term alcohol withdrawal increased the density of immunolabelled cells in DDR. In addition, chronic exposure, as well as short- and long-term withdrawal periods increased immunostaining in CDR, when compared to control animals.