Elizabeth J Burnett1, Kathleen A Grant2, April T Davenport3, Scott E Hemby1, David P Friedman4. 1. Neuroscience Program, Wake Forest University School of Medicine, Winston-Salem, NC, USA; Department of Physiology & Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, USA. 2. Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, USA. 3. Department of Physiology & Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, USA. 4. Neuroscience Program, Wake Forest University School of Medicine, Winston-Salem, NC, USA; Department of Physiology & Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, USA. Electronic address: dfriedmn@wakehealth.edu.
Abstract
BACKGROUND: Chronic alcohol consumption reduces brain serotonin and alters the synaptic mechanisms involved in memory formation. Hippocampal 5-HT1A receptors modulate these mechanisms, but the neuroadaptive response of 5HT1A receptors to chronic alcohol self-administration is not well understood. METHODS: Hippocampal tissue from monkeys that voluntarily self-administered ethanol for 12 months (n=9) and accompanying controls (n=8) were prepared for in vitro receptor autoradiography and laser capture microdissection. The 5-HT1A receptor antagonist, [(3)H]MPPF, and the agonist, [(3)H]8-OH-DPAT, were used to measure total and G-protein coupled 5-HT1A receptors respectively. The expression of the genes encoding the 5-HT1A receptor and its trafficking protein Yif1B was measured in microdissected dentate gyrus (DG) granule cells and CA1 pyramidal neurons. RESULTS: An increase in G-protein coupled, but not total, receptors was observed in the posterior pyramidal cell layer of CA1 in ethanol drinkers compared to controls. Chronic ethanol self-administration was also associated with an up-regulation of total and G-protein coupled 5-HT1A receptors in the posterior DG polymorphic layer. Changes in receptor binding were not associated with concomitant changes in 5-HT1A receptor mRNA expression. Chronic ethanol self-administration was associated with a significant increase in Yif1B gene expression in posterior CA1 pyramidal neurons. CONCLUSIONS: Chronic, ethanol self-administration up-regulates hippocampal 5-HT1A receptor density in a region-specific manner that does not appear to be due to alterations at the level of transcription but instead may be due to increased receptor trafficking. Further exploration of the mechanisms mediating chronic ethanol-induced 5-HT1A receptor up-regulation and how hippocampal neurotransmission is altered is warranted.
BACKGROUND:Chronic alcohol consumption reduces brain serotonin and alters the synaptic mechanisms involved in memory formation. Hippocampal 5-HT1A receptors modulate these mechanisms, but the neuroadaptive response of 5HT1A receptors to chronic alcohol self-administration is not well understood. METHODS: Hippocampal tissue from monkeys that voluntarily self-administered ethanol for 12 months (n=9) and accompanying controls (n=8) were prepared for in vitro receptor autoradiography and laser capture microdissection. The 5-HT1A receptor antagonist, [(3)H]MPPF, and the agonist, [(3)H]8-OH-DPAT, were used to measure total and G-protein coupled 5-HT1A receptors respectively. The expression of the genes encoding the 5-HT1A receptor and its trafficking protein Yif1B was measured in microdissected dentate gyrus (DG) granule cells and CA1 pyramidal neurons. RESULTS: An increase in G-protein coupled, but not total, receptors was observed in the posterior pyramidal cell layer of CA1 in ethanol drinkers compared to controls. Chronic ethanol self-administration was also associated with an up-regulation of total and G-protein coupled 5-HT1A receptors in the posterior DG polymorphic layer. Changes in receptor binding were not associated with concomitant changes in 5-HT1A receptor mRNA expression. Chronic ethanol self-administration was associated with a significant increase in Yif1B gene expression in posterior CA1 pyramidal neurons. CONCLUSIONS: Chronic, ethanol self-administration up-regulates hippocampal 5-HT1A receptor density in a region-specific manner that does not appear to be due to alterations at the level of transcription but instead may be due to increased receptor trafficking. Further exploration of the mechanisms mediating chronic ethanol-induced 5-HT1A receptor up-regulation and how hippocampal neurotransmission is altered is warranted.
Authors: Jo Vandesompele; Katleen De Preter; Filip Pattyn; Bruce Poppe; Nadine Van Roy; Anne De Paepe; Frank Speleman Journal: Genome Biol Date: 2002-06-18 Impact factor: 13.583
Authors: Ansel T Hillmer; Dustin W Wooten; Dana L Tudorascu; Todd E Barnhart; Elizabeth O Ahlers; Leslie M Resch; Julie A Larson; Alexander K Converse; Colleen F Moore; Mary L Schneider; Bradley T Christian Journal: Drug Alcohol Depend Date: 2014-08-29 Impact factor: 4.492
Authors: R Cervera-Juanes; L J Wilhem; B Park; R Lee; J Locke; C Helms; S Gonzales; G Wand; S R Jones; K A Grant; B Ferguson Journal: Mol Psychiatry Date: 2015-07-07 Impact factor: 15.992