Cerebral Cortical Morphology and Behavior in Rats Following Acute Prenatal Ethanol Exposure

Abstract

Cerebral cortical morphology and early motor development were evaluated in offspring from ethanol-exposed mothers, pairfed control mothers and ad libitum control rats. Ethanol-exposed rats received a total dose of 18 g/kg of ethanol by intubation on gestational Days 14 and 15, a critical period of development of the cerebral cortex. Pairfed control mothers received isocaloric sucrose on gestational Days 14 and 15 and were pairfed to ethanol-exposed animals from gestational Day 12 through gestational Day 20. Ethanol-exposed offspring weighed significantly less than control offspring from postnatal Day 7 through postnatal Day 28. Ethanol-exposed offspring also showed significant delays in reflex suspension (time an animal maintained its grip on a crossbar) and continuous corridor (number of turns in 5 min). The thickness of the cerebral cortex of ethanol-exposed offspring was significantly different from ad libitum and pairfed control offspring on postnatal Day 1. However, only Layer V and total cortical thickness were affected in ethanol-exposed offspring on postnatal Day 28. The results of this study indicate that ethanol exposure during a critical period of development causes alterations in central nervous system development and developmental delays.

Prenatal Alcohol Exposure is Associated with Regionally Thinner Cortex During the Preadolescent Period

“…Like Zhou et al (2011) we found thinner cortex in right superior parietal and middle temporal fusiform, calcarine, and lingual gyri. These findings are also consistent with the animal studies showing thinner cortex in alcohol-exposed animals relative to controls (Miller and Dow-Edwards 1988;Norton et al 1988;Kotkoskie and Norton 1989;Leigland et al 2013). Previous studies of cortical thickness in FASD have assessed samples that included both preadolescent and adolescent subjects.…”

“…Prenatal exposure to teratogens, such as maternal cigarette smoking (Derauf et al 2012;El Marroun et al 2013), cocaine (Liu et al 2013), opiates (Walhovd et al 2007), and organosphate pesticide (Rauh et al 2012) has also been associated with thinner cortex. In animal studies, rats prenatally exposed to alcohol have shown thinner cortex relative to controls (Miller and Dow-Edwards 1988;Norton et al 1988), particularly in layer V (Kotkoskie and Norton 1989), which persists through multiple postnatal time-points (Leigland et al 2013), particularly in primary sensory areas. Similarly, in adults one of the effects of excessive alcohol consumption is a reduction in cortical thickness compared with healthy controls (Durazzo and Tosun 2011;Fortier and Leritz 2011;Momenan et al 2012).…”

Chromatin Switches during Neural Cell Differentiation and Their Dysregulation by Prenatal Alcohol Exposure

“…During the neurogenic period, alcohol causes a decrease in a variety of neuronal populations including hippocampal CA1 pyramidal cells [102,103,104,105,106,107,108,109,110,111], cerebellar Purkinje cells [112,113,114,115], and cerebral cortical neurons [116,117]. These effects may be caused by both a disruption of neuronal generation when exposure occurs earlier in gestation, and neuronal apoptosis when exposure occurs later in gestation during defined sensitive periods [103,116,118,119,120,121,122]. …”

Modeling the Impact of Alcohol on Cortical Development in a Dish: Strategies from Mapping Neural Stem Cell Fate

“…An early study by Barnes and Walker (37) reported a loss of hippocampal neurons from a second-trimester equivalent alcohol exposure, and significant work from Miller's lab showed alcohol-induced changes in cortical neuronogenesis (38)(39)(40). Others have shown that rats exposure to ethanol over a 2-d window from, G. D.14-15 exhibit an immediate enlargement of the, S.V.Z, suggesting, N.S.C/NPC maturation (41), disorganized cortical architecture at the end of the neuronogenic period (42), and a persistent thinning of lamina V of the rodent cerebral cortex (43), suggesting that the effects of second-trimester ethanol exposure are persistent.…”