Effects of Fluoxetine,Indomethacine and Placebo on 3α, 5α Tetrahydroprogesterone (THP) Plasma Levels in Uncomplicated Alcohol Withdrawal

Summary

Objective: The purpose of this study was to investigate the effects of fluoxetine (F) and indomethacine (I), two drugs that regulate the synthesis of the GABAergic neurosteroid 3α, 5α tetrahydroprogesterone (allopregnanolone, THP) on THP plasma levels and on symptoms of anxiety and depression in alcoholics during ethanol withdrawal.

Method: Patients who met DSM-IV criteria for alcohol abuse were randomly assigned to treatment with F (40 mg/day) plus misoprostol (M) (500 mg/day) or I (100 mg/day) plus M or placebo (PL) plus M. Patients were rated with the Hamilton Anxiety (14-HAS) and Depression (17-HDS) scales on days 1, 5, 7, 15 and 28 of ethanol withdrawal and with a Visual Analogue Scale for Depression (VASD) and a Visual Analogue Scale for Anxiety (VASA) on days 1, 2, 4, 5, 7, 15 and 28 of withdrawal. On the same days a plasma sample was collected to measure the concentrations of THP by means of a very sensitive gas chromatographic mass spectrometric method.

Results: During withdrawal at days 1, 2, 4 and 5, THP plasma values were lower and symptoms of anxiety and depression were significantly higher compared to the late withdrawal phase at days 15 and 28. In the F or I treatment, the depression and anxiety score, measured by VASD and VASA, decreased significantly at day 5-7 whereas THP plasma levels significantly increased compared to PL condition.

Conclusions: Treatment of alcohol withdrawal either with F or I reduced the extent of anxiety and depression and normalised THP plasma levels that were decreased during withdrawal.     

Adolescent intermittent ethanol exposure diminishes anhedonia during ethanol withdrawal in adulthood

Adolescent alcohol use may interfere with neurodevelopment, increasing the likelihood of adult alcohol use disorders (AUDs). We investigated whether adolescent intermittent ethanol (AIE) exposure alters the adult reward response to ethanol. Adolescent rats were administered ethanol once (moderate exposure; Cohort 1) or three times per day (severe exposure; Cohort 2) in a 2 days on/2 days off pattern. In adulthood, subjects responded for electrical stimulation directed at the posterior lateral hypothalamus in a discrete-trial intracranial self-stimulation (ICSS) procedure that provides current-intensity thresholds as a measure of brain reward function. The effects of ethanol administration and withdrawal were assessed. Control rats showed dose-dependent threshold elevations after acute ethanol, indicating reward deficits. A majority of moderately AIE-exposed rats (Cohort 1) showed threshold lowering after ethanol, suggesting ethanol-induced reward enhancement in this sub-set of rats. Rats exposed to severe AIE (Cohort 2) showed no threshold elevation or lowering, suggesting a blunted affective ethanol response. Daily ethanol induced threshold elevations 24 h after administration in control rats but not in either group of AIE-exposed rats, suggesting decreased sensitivity to the negative affective state of ethanol withdrawal. Withdrawal from a 4-day ethanol binge produced robust and enduring threshold elevations in all rats, although threshold elevations were diminished in rats exposed to severe AIE. These results indicate that AIE exposure diminished reward deficits associated with ethanol intoxication and withdrawal and may have increased ethanol-induced reward enhancement in a sub-set of rats. In humans, enhanced ethanol reward accompanied by reduced withdrawal severity may contribute to the development of AUDs.     

Acute effects of alcohol on brain perfusion monitored with arterial spin labeling magnetic resonance imaging in young adults

While a number of studies have established that moderate doses of alcohol increase brain perfusion, the time course of such an increase as a function of breath alcohol concentration (BrAC) has not yet been investigated, and studies differ about regional effects. Using arterial spin labeling (ASL) magnetic resonance imaging, we investigated (1) the time course of the perfusion increase during a 15-minute linear increase of BrAC up to 0.6 g/kg followed by a steady exposure of 100 minutes, (2) the regional distribution, (3) a potential gender effect, and (4) the temporal stability of perfusion effects. In 48 young adults who participated in the Dresden longitudinal study on alcohol effects in young adults, we observed (1) a 7% increase of global perfusion as compared with placebo and that perfusion and BrAC are tightly coupled in time, (2) that the increase reaches significance in most regions of the brain, (3) that the effect is stronger in women than in men, and (4) that an acute tolerance effect is not observable on the time scale of 2 hours. Larger studies are needed to investigate the origin and the consequences of the effect, as well as the correlates of inter-subject variations.     

Mifepristone in the Central Nucleus of the Amygdala Reduces Yohimbine Stress-Induced Reinstatement of Ethanol-Seeking

Chronic ethanol exposure leads to dysregulation of the hypothalamic-pituitary-adrenal axis, leading to changes in glucocorticoid release and function that have been proposed to maintain pathological alcohol consumption and increase vulnerability to relapse during abstinence. The objective of this study was to determine whether mifepristone, a glucocorticoid receptor antagonist, plays a role in ethanol self-administration and reinstatement. Male, Long–Evans rats were trained to self-administer either ethanol or sucrose in daily 30 min operant self-administration sessions using a fixed ratio 3 schedule of reinforcement. Following establishment of stable baseline responding, we examined the effects of mifepristone on maintained responding and yohimbine-induced increases in responding for ethanol and sucrose. Lever responding was extinguished in separate groups of rats and animals were tested for yohimbine-induced reinstatement and corticosterone release. We also investigated the effects of local mifepristone infusions into the central amygdala (CeA) on yohimbine-induced reinstatement of ethanol- and sucrose-seeking. In addition, we infused mifepristone into the basolateral amygdala (BLA) in ethanol-seeking animals as an anatomical control. We show that both systemic and intra-CeA (but not BLA) mifepristone administration suppressed yohimbine-induced reinstatement of ethanol-seeking, while only systemic injections attenuated sucrose-seeking. In contrast, baseline consumption, yohimbine-induced increases in responding, and circulating CORT levels were unaffected. The data indicate that the CeA plays an important role in the effects of mifepristone on yohimbine-induced reinstatement of ethanol-seeking. Mifepristone may be a valuable pharmacotherapeutic strategy for preventing relapse to alcohol use disorders and, as it is FDA approved, may be a candidate for clinical trials in the near future.