Clozapine reduces alcohol drinking in Syrian golden hamsters.

Alcohol abuse contributes substantially to the overall morbidity of schizophrenia. While typical antipsychotic medications do not limit alcohol use in patients with schizophrenia, emerging data suggest that the atypical antipsychotic clozapine does. To further elucidate the effects of these antipsychotics on alcohol use, we initiated a study in alcohol-preferring rodents. Syrian golden hamsters were given free-choice, unlimited access to alcohol. Nine days of treatment (s.c. injection) with clozapine (2-4 mg/kg/day), but not haloperidol (0.2-0.4 mg/kg/day), reduced alcohol drinking. Clozapine reduced alcohol drinking by 88% (from 11.3+/-1.7 to 1.4+/-0.2 g/kg/day) while increasing both water and food intake. Alcohol drinking gradually (during 24 days) returned toward baseline in the clozapine-treated animals when vehicle was substituted for clozapine. Further increasing the doses of haloperidol (0.6-1.0 mg/kg/day) had no effect on alcohol drinking; moreover, very low doses of haloperidol (0.025-0.1 mg/kg/day) tested in separate groups of hamsters also had no effect on alcohol drinking. This study demonstrates that clozapine, but not haloperidol, can effectively and reversibly decrease alcohol consumption in alcohol-preferring hamsters. The results are compatible with the observations that clozapine, but not haloperidol, limits alcohol use in patients with schizophrenia. These data further suggest that clozapine may serve as a prototype for developing novel treatments for alcohol abuse.

Neuropsychological deficits among patients with late-onset minor and major depression.

Cognitive ability of minor depressed patients (N=28), major depressed patients (N=26) and healthy elderly (N=38) was examined cross-sectionally to determine if cognitive abilities of patients with late-onset depression decrease with increasing severity of disease and if cognitive scores for minor depressed patients fall between those of healthy elderly and major depressed patients. A pooled within-group principal component analysis of cognitive test scores identified five components, three of which showed significant group differences. Verbal Recall and Maintenance of Set separated controls from major depressed patients and minor from major depressed patients. Executive Functioning separated controls from minor depressed patients, and Working Memory was borderline for separating controls from major depressed patients. The component representing Nonverbal Recognition was not statistically significant. Partial correlations controlling for age and education indicate that cognitive performance does decrease as severity of depression increases, and the magnitude of the change varies from a trend to a significant deficit depending on the cognitive domain. This decline in cognitive performance parallels a similar trend observed in neuroanatomical studies in which the volume of the frontal and temporal lobes decrease with increasing severity of depression.