Prenatal ethanol exposure differentially affects hippocampal neurogenesis in the adolescent and aged brain.
Exposure to ethanol in utero is associated with a myriad of sequelae for the offspring. Some of these effects are morphological in nature and noticeable from birth, while others involve more subtle changes to the brain that only become apparent later in life when the individuals are challenged cognitively. One brain structure that shows both functional and structural deficits following prenatal ethanol exposure is the hippocampus. The hippocampus is composed of two interlocking gyri, the cornu ammonis (CA) and the dentate gyrus (DG), and they are differentially affected by prenatal ethanol exposure. The CA shows a more consistent loss in neuronal numbers, with different ethanol exposure paradigms, than the DG, which in contrast shows more pronounced and consistent deficits in synaptic plasticity. In this study we show that significant deficits in adult hippocampal neurogenesis are apparent in aged animals following prenatal ethanol exposure. Deficits in hippocampal neurogenesis were not apparent in younger animals. Surprisingly, even when ethanol exposure occurred in conjunction with maternal stress, deficits in neurogenesis did not occur at this young age, suggesting that the capacity for neurogenesis is highly conserved early in life. These findings are unique in that they demonstrate for the first time that deficits in neurogenesis associated with prenatal ethanol consumption appear later in life.
Division of Medical Sciences, Island Medical Program, University of Victoria, Victoria, British Columbia, Canada. Electronic address: jgil@uvic.ca.
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Gil-Mohapel
Division of Medical Sciences, Island Medical Program, University of Victoria, Victoria, British Columbia, Canada. Electronic address: okayandrea@gmail.com.
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Titterness
Division of Medical Sciences, Island Medical Program, University of Victoria, Victoria, British Columbia, Canada. Electronic address: anna.r.patten@gmail.com.
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Patten
Division of Medical Sciences, Island Medical Program, University of Victoria, Victoria, British Columbia, Canada. Electronic address: slf@uvic.ca.
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Taylor
Division of Medical Sciences, Island Medical Program, University of Victoria, Victoria, British Columbia, Canada. Electronic address: aef@uvic.ca.
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Ratzlaff
Division of Medical Sciences, Island Medical Program, University of Victoria, Victoria, British Columbia, Canada. Electronic address: timothy_ratzlaff@hotmail.com.
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Ratzlaff
Division of Medical Sciences, Island Medical Program, University of Victoria, Victoria, British Columbia, Canada. Electronic address: helferj@gmail.com.
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Helfer
Division of Medical Sciences, Island Medical Program, University of Victoria, Victoria, British Columbia, Canada; The Brain Research Centre and Program in Neuroscience, University of British Columbia, Vancouver, British Columbia, Canada; The Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, British Columbia, Canada. Electronic address: brain64@uvic.ca.
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Christie
D000818:Animals; D002492:Central Nervous System Depressants / Q000097:blood / Q000633:toxicity; D000431:Ethanol / Q000097:blood / Q000633:toxicity; D005260:Female; D063647:Fetal Alcohol Spectrum Disorders / Q000503:physiopathology*; D006624:Hippocampus / Q000187:drug effects / Q000254:growth & development* / Q000503:physiopathology*; D008297:Male; D055495:Neurogenesis / Q000187:drug effects / Q000502:physiology*; D009474:Neurons / Q000187:drug effects / Q000502:physiology; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000503:physiopathology*; D017207:Rats, Sprague-Dawley; D012149:Restraint, Physical; D012727:Sex Characteristics; D013315:Stress, Psychological / Q000503:physiopathology*
D002492:Central Nervous System Depressants; D000431:Ethanol
Fetal Alcohol Spectrum Disorders; adult hippocampal neurogenesis; age; prenatal ethanol exposure; prenatal stress