The hypothalamopituitary-adrenal axis and alcohol preference

Effects of alterations in stress hormones and their actions were investigated on alcohol preference, by intraperitoneal administration of RU38486 (a Type II glucocorticoid receptor antagonist, also given by the intracerebroventricular route), spironolactone (a Type I glucocorticoid receptor antagonist), metyrapone (a corticosterone synthesis inhibitor), corticosterone, adrenocorticotropin (ACTH1-39), or intracerebroventricular injection of corticotropin releasing factor (CRF) or a CRF antagonist (alpha-helical CRF9-41). Intracerebroventricular or intraperitoneal administration of RU38486 did not alter the alcohol consumption of mice with high preference for alcohol, or, on first administration, the intake of those with low alcohol preference. When given by repeated intraperitoneal injection however this drug prevented the increase in alcohol consumption seen in "low preference" mice after 3 weeks vehicle injections. Spironolactone did not alter alcohol preference when given by intracerebroventricular or intraperitoneal routes. Repeated, but not single, administration of metyrapone reduced alcohol preference in both high and low preference animals and prevented the increase from low alcohol preference caused by repeated vehicle injections. ACTH1-39 or corticosterone administered by single or repeated intraperitoneal injection, or CRF given i.c.v., did not alter alcohol preference, but the CRF antagonist, alpha-helical CRF9-41, caused a transient increase from low alcohol preference. Blood corticosterone concentrations prior to preference measurements did not correlate with the alcohol preference of the mice. The results indicate that delayed consequences of corticosterone acting on Type II glucocorticoid receptors may be involved in the increases in alcohol preference after injection stress. They also suggest that central actions of CRF may influence the low alcohol consumption of the low alcohol-preferring mice.