Contrasting effects of adolescent and early-adult ethanol exposure on prelimbic cortical pyramidal neurons

• Published in: Drug and alcohol dependence Vol. 216; p. 108309
• Main Authors: Galaj, Ewa, Guo, Changyong, Huang, Donald, Ranaldi, Robert, Ma, Yao-Ying
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 01.11.2020; Elsevier Science Ltd
• Subjects: Adolescence; Adolescents; Adults; Age Factors; Alcohol use; Amplitudes; Animals; Binge drinking; Brain; Child development; Chronic intermittent ethanol; Cortex; Cytology; Dendritic spine; Dendritic spines; Density; Developmental stages; Drinking behavior; Drinking water; Early-adulthood; Ethanol; Ethanol - administration & dosage; Excitability; Excitatory post-synaptic current; Intermittent; Intrinsic excitability; Male; Morphology; Neurons; Neurons - drug effects; Neurons - physiology; Organ Culture Techniques; Prefrontal Cortex - drug effects; Prefrontal Cortex - growth & development; Prelimbic cortex; Pyramidal cells; Pyramidal Cells - drug effects; Pyramidal Cells - physiology; Rats; Rats, Sprague-Dawley; Spine; Teenagers; Young adults; Intrinsic excitability; Excitatory post-synaptic current; Adolescence; Chronic intermittent ethanol; Early-adulthood; Dendritic spine; Prelimbic cortex
• ISSN: 0376-8716; 1879-0046; 1879-0046
• DOI: 10.1016/j.drugalcdep.2020.108309

•Layer 5 (L5) but not layer 2 (L2) pyramidal neurons in the prelimbic cortex (PrL) were modified by chronic intermittent ethanol (CIE).•No changes in PrL-L5 neurons were detected 2 days after either adolescent or early-adult CIE.•Intrinsic excitability of PrL-L5 was increased by adolescent CIE, but decreased by early-adult CIE after a protracted withdrawal period.•Synaptic transmission and dendritic spines in PrL-L5 were decreased 21 days after adolescent CIE, but increased 21 days after early-adult CIE. Adolescence and early-adulthood are vulnerable developmental periods during which binge drinking can have long-lasting effects on brain function. However, little is known about the effects of binge drinking on the pyramidal cells of the prelimbic cortex (PrL) during early and protracted withdrawal periods. In the present study, we performed whole-cell patch clamp recordings and dendritic spine staining to examine the intrinsic excitability, spontaneous excitatory post-synaptic currents (sEPSCs), and spine morphology of pyramidal cells in the PrL from rats exposed to chronic intermittent ethanol (CIE) during adolescence or early-adulthood. Compared to chronic intermittent water (CIW)-treated controls, the excitability of PrL-L5 pyramidal neurons was significantly increased 21 days after adolescent CIE but decreased 21 days after early-adult CIE. No changes of excitability in PrL Layer (L) 5 were detected 2 days after either adolescent or early-adulthood CIE. Interestingly, decreases in sEPSC amplitude and increases in thin spines ratio were detected 2 days after adolescent CIE. Furthermore, decreased frequency and amplitude of sEPSCs, accompanied by a decrease in the density of total spines and non-thin spines were observed 21 days after adolescent CIE. In contrast, increased frequency and amplitude of sEPSCs, accompanied by increased densities of total spines and non-thin spines were found 21 days after early adult CIE. CIE produced prolonged neuronal and synaptic alterations in PrL-L5, and the developmental stage, i.e., adolescence vs. early-adulthood when subjects receive CIE, is a key factor in determining the direction of these changes.