Adult rat cortical thickness changes across age and following adolescent intermittent ethanol treatment. (1st February 2016)

• Record Type: Journal Article
• Authors: Vetreno, Ryan P.; Yaxley, Richard; Paniagua, Beatriz; Johnson, G. Allan; Crews, Fulton T.
• Is Part Of: Addiction biology. Volume 22:Number 3(2017)
• Page Start: 712
• Page End: 723
• Publication Date: 2016-02-01
• Subjects: adolescence -- alcohol -- binge drinking -- cortical thickness -- development; Substance abuse -- Periodicals; Substance abuse -- Physiological aspects -- Periodicals; Substance-Related Disorders -- periodicals; 616.86
• DOI: 10.1111/adb.12364
• Languages: English
• ISSNs: 1355-6215

Abstract

Abstract: Human studies have established that adolescence is a period of brain maturation that parallels the development of adult behaviors. However, little is known regarding cortical development in the adult rat brain. We used magnetic resonance imaging (MRI) and histology to assess the impact of age on adult Wistar rat cortical thickness on postnatal day (P)80 and P220 as well as the effect of adolescent binge ethanol exposure on adult (P80) cortical thickness. MRI revealed changes in cortical thickness between P80 and P220 that differ across cortical region. The adult P220 rat prefrontal cortex increased in thickness whereas cortical thinning occurred in both the cingulate and parietal cortices relative to young adult P80 rats. Histological analysis confirmed the age‐related cortical thinning. In the second series of experiments, an animal model of adolescent intermittent ethanol (AIE; 5.0 g/kg, intragastrically, 20 percent ethanol w/v, 2 days on/2 days off from P25 to P55) was used to assess the effects of alcohol on cortical thickness in young adult (P80) rats. MRI revealed that AIE resulted in region‐specific cortical changes. A small region within the prefrontal cortex was significantly thinner whereas medial cortical regions were significantly thicker in young adult (P80) AIE‐treated rats. The observed increase in cortical thickness was confirmed by histology. Thus, the rat cerebral cortex continues to undergo cortical thickness changes into adulthood, and adolescent alcohol exposure alters the young adult cortex that could contribute to brain dysfunction in adulthood. Abstract : Magnetic resonance imaging and histology was used to determine the effect of ageing and adolescent binge ethanol exposure on cortical thickness in adult rats. We discovered that the cerebral cortex continues to undergo age‐associated cortical thinning and expansion into adulthood, which was altered by prior adolescent binge ethanol exposure. These data reveal that the cerebral cortex continues to undergo refinement into adulthood and that adolescent binge ethanol treatment alters adult cortical thickness that might contribute to behavioural dysfunction.