Anxiolytic effects of diazepam and ethanol in two behavioral models: comparison of males and females.
The present study compared the anxiolytic effects of the benzodiazepine agonist diazepam and ethanol in adult male and female rats. Varying doses of diazepam (1-3 mg/kg) or ethanol (0.5-2.0 g/kg) were tested using both the elevated plus maze and defensive prod-burying models. Two time points following ethanol administration (10 and 30 min) were tested in the plus maze. Sex differences were seen in some anxiety-related behaviors, with females showing greater open arm time and reduced burying behavior than males. Although this suggests females displayed less anxiety-like behavior than males, the differences in the plus maze were not observed in all testing situations. Both diazepam and ethanol dose-dependently increased open arm times in the plus maze and reduced burying behavior in the defensive prod-burying task. The parallel nature of the dose-response curves suggests that both diazepam and ethanol have similar anxiolytic effects in males and females. No sex differences were seen in the brain levels of diazepam-like activity or blood alcohol levels with these treatments. A greater corticosterone response was observed in females than males with these two behavioral tests, but neither diazepam nor ethanol decreased this response. These results suggest a dissociation between the anxiety-reducing influences of these compounds and the changes in stress-related endocrine responses.
Wilson
Marlene A
MA
Department of Pharmacology, Physiology and Neuroscience, University of South Carolina School of Medicine, Building 1, D26 Columbia, SC 29208, USA. marlene@med.sc.edu
Burghardt
Paul R
PR
Ford
Kris A
KA
Wilkinson
Matthew B
MB
Primeaux
Stefany D
SD
D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology*; D001522:Behavior, Animal / Q000187:drug effects*; D003345:Corticosterone / Q000097:blood; D003975:Diazepam / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D000431:Ethanol / Q000494:pharmacology*; D005260:Female; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D051381:Rats; D020318:Rats, Long-Evans; D011963:Receptors, GABA-A / Q000187:drug effects; D012727:Sex Characteristics
D014151:Anti-Anxiety Agents; D011963:Receptors, GABA-A; D000431:Ethanol; D003975:Diazepam; D003345:Corticosterone