Figure 1
Ethanol intake and BECs increase over weeks of repeated exposure. (a) Schematic diagram of the 6-week long ‘Drinking in the Dark’ protocol with arrows representing 2 h (black) and 4 h (gray) sessions and marking the time for the morphological and electrophysiological studies. (b) Daily ethanol consumption during 2 h and 4 h sessions. (c) Average daily ethanol intake was significantly greater during the last 3 weeks (dark gray) than for the first 3 weeks (light gray) during both the 2-h and 4-h sessions. *Denotes P<0.01. (d) Average BEC recorded after 2 h (black) and 4 h (gray) sessions over the weeks. Dotted line marks 80 mg/dl, the legal limit for intoxication in humans (n=25–29 mice). (e) Top, timeline of the locomotor activity experiments. Mice received water under the DID schedule and were habituated to the beam break recording equipment for 6 weeks before the first ethanol exposure. Left, locomotor activity (mean±SEM beam breaks per 10 min) during DID 2 h sessions with access to water bottles (open circles) and a single 2 h session with access to ethanol (black circles) (n=6 mice). Right, total beam breaks per 2 h session for session with access to water (open) and for sessions with 20% ethanol (solid). (f) Individual variability in average BEC achieved during 2 h and 4 h sessions (n=25–29 mice). Dotted line marks the legal limit for intoxication in humans, 80 mg/dl. (g) Average BEC per mouse plotted as a function of the average ethanol intake for 2 h (black) and 4 h (gray) sessions (n=25–29 mice). Dotted line represents the linear fit (r2=0.14). Markers/bars and lines represent mean±SEM.
