Neurodegeneration, Neuroprotection, and Disease-Oriented NeuroscienceResearch PaperPeriadolescent ethanol exposure reduces adult forebrain ChAT+IR neurons: correlation with behavioral pathology
Highlights
▶Adolescence ethanol exposure produces disinhibitory behavior at 2 weeks withdrawal. ▶Adolescence ethanol exposure produces depressive-like behavior at 2 weeks withdrawal. ▶Adolescent ethanol exposure reduced cholinergic neurons in basal forebrain. ▶Reduced cholinergic neurons were correlated with more disinhibitory behavior.
Section snippets
Subjects
Male Wistar rats who were received at postnatal day (PD) 23 (n=42; 36 juveniles, six dams, Charles River, USA) were used in this study. The adolescent animals (PD 23) were housed three per cage respectively in standard cages for the duration of the experiment. Animals were kept in a light/dark (12 h light/12 h dark, lights on at 6:00 am) and temperature-controlled environment. Food and water were available ad libitum throughout the experiment, except where noted. All experimental protocols were
Body weight and BACs
As seen in Fig. 1, all rats gained weight over the course of the experiment. Rats grew in both groups from about 50 g at PD 22 to about 360 g being 373.6 (±9.4) and 352.1 (±6.8) for control and ethanol at PD 72 respectively. Ethanol vapor–exposed rats showed parallel increases in weight gain to controls, although ethanol vapor rats had slightly reduced body weights at 3 of the 27 weightings, for example, at ages PD 48, PD 52, and PD 55 (P<0.05) as seen in Fig. 1. Both groups had similar body
Discussion
In the present study, rats were exposed to ethanol vapors during the periadolescent period in order to examine ethanol's effects on cholinergic neurons in the basal forebrain and correlated behavioral changes. Ethanol vapor–exposed rats displayed increased locomotor activity 8 h after the termination of vapor delivery for that 24 h period at day 10 and day 20 of alcohol vapor exposure, significant reductions in the amplitude of their responses to prepulse stimuli during the startle paradigm at
Conclusions
Our data suggest that rats exposed to daily ethanol vapor for 5 weeks over the adolescent period display increased locomotor activity 8 h after the termination of vapor delivery for that 24 h period at day 10 and day 20 of alcohol vapor exposure, significant reductions in the amplitude of their responses to prepulse stimuli during the startle paradigm at 24 h withdrawal, and at 2 weeks following withdrawal, less anxiety-like and/or more “disinhibitory” behavior in the open field conflict, and
Acknowledgments
This study was supported in part by the NADIA Initiative Project of the NIH National Institute on Alcoholism and Alcohol Abuse grants AA019969 (C.L.E.) and AA020022, AA020023 and AA020024 (F.T.C.) and the UNC Bowles Center for Alcohol Studies. The authors thank Greta Berg for her assistance in data collection and Shirley Sanchez for editing the manuscript.
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