The effect of alcohol on testosterone and corticosterone levels in alcohol-preferring and non-preferring rat lines
Year: 2008
Type: article
Abstract: The large individual variation in the disposition of alcohol dependence has been explained by a combination of a range of both environmental and genetic factors. One possible genetic factor is the steroid hormone testosterone, or more precisely, differences in the concentrations of this hormone. A subgroup of alcoholics has been described to possess characteristics, which also have been associated with high testosterone levels. Furthermore, this subgroup generally begins drinking in early adolescence, which is when testosterone levels increase in boys. Briefly, this could explain why alcoholism is more common among men than women. Male rats of AA and ANA rat lines, developed for high and low alcohol preference respectively, were used in this study. The AA rats represent an animal model of human alcoholics and large-scale consumers, while the ANA rats are comparable to abstainers and individuals consuming very small amounts of alcohol. The development of these rat lines was based solemnly on the animals’ free will to drink alcohol, and therefore, any differences between the lines ought to be connected to alcohol drinking. The aims of this study were to investigate if the AA and ANA rat lines differ in control and/or alcohol-induced levels of testosterone and corticosterone, and if a mildly stressful situation affects the alcoholinduced changes in testosterone. Stress has been reported to induce alcohol drinking although alcohol drinking per se has been shown to increase stress hormone levels. Half of the experimental animals of each rat line were housed in groups of four and half were housed individually. All animals were subjected to all treatment groups, which varied by alcohol dose (control, 0.75g/kg, 1.5g/kg alcohol) and time of day (morning and afternoon). Blood samples were collected before as well as 1, 2 and 3 hours post injection of the control or alcohol dose. Testosterone and corticosterone levels were measured from serum samples using radioimmunological techniques. The AA rats were shown to have higher testosterone levels than the ANA rats. The high alcohol dose reduced testosterone levels of group-housed rats of both rat lines, while the low dose only had a reducing effect in the ANA rats. Social isolation attenuated the effects of alcohol on testosterone. In isolated rats, the only testosterone-reducing effect of alcohol was following the high dose in the ANA rats in the afternoon session. The results of this study support a role of testosterone in alcohol drinking, although this role seems to be complex. The role of testosterone in alcohol drinking may be enhanced in individuals with a genetic disposition for becoming dependent on alcohol and modulated by stress.
Author: Susanna Apter
Language: English
Subfield: Behavioral Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W834686984