Nicotinic acetylcholine receptors (nAChRs) in the ventral tegmental area (VTA) and their effects on signaling in the nucleus accumbens (NAc) are important for the behavioral actions of nicotine related to addiction. Our hypothesis is that there is a dissociation between nicotine reward and locomotor activation. We hypothesize that nicotine reward necessitates activation of D1 receptors and increased CREB activity in the NAc shell, whereas DA receptor activation in the NAc core is sufficient for locomotor activation, and CREB activity is not necessary. We have used transgenic mice with expression of the beta2-subunit of the nAChR on VTA neurons that project to the NAc core to test the idea that these receptors are sufficient for nicotine-dependent locomotor activation. Preliminary studies show that these mice show relatively normal nicotine-dependent locomotor activation but do not show a place preference for nicotine or activation of CREB in the NAc core.
Aim 1 of this project will be to determine whether CREB activity in the NAc shell, but not core, is critical for nicotine reward using viral-mediated gene transfer and complementary pharmacological approaches. In addition we will determine whether the balance between D1 vs. D2 signaling is important for CREB activity in the NAc shell or core, and nicotine reward.
Aim 2 will determine whether DA release in the NAc core and not the shell is sufficient for nicotine-mediated locomotor activation, and determine the subsequent effects on CREB activation in the NAc. These experiments are significant because they could explain the very sharp dose-response function for nicotine reward and may provide new points of intervention to support smoking cessation. They will help identify the molecular mechanisms and signaling pathways involved in nicotine locomotion and reward, and determine the role of D1 and D2 receptor activation in these behaviors. These studies will test the hypothesis that CREB activity in the NAc shell integrates D1 and D2 signaling and is a critical output underlying nicotine reward.
We know that nicotine is the primary agent in tobacco that leads to addiction. Nicotine changes the strength of communication between nerve cells and this is thought to be responsible for the long-term changes in behavior that results from smoking, including long-lasting increases in cigarette craving and the likelihood to relapse. We have shown that activity of CREB, a molecule that is known to be important for changing the connections between nerve cells, is necessary for nicotine to be rewarding in mice. We have also shown using genetically-manipulated mice that nicotine receptors on a group of nerve cells in the brain's reward center that communicate with what is called the core of the nucleus accumbens are sufficient for the ability of nicotine to act as a stimulant, but not nicotine reward. We believe that nicotine receptors on nerve cells that communicate with the nucleus accumbens shell are important for nicotine reward, whereas nicotine receptors on nerve cells that communicate with the nucleus accumbens core are important for nicotine's stimulant properties. These two pathways can be distinguished genetically, but may also be sensitive to different drugs. We propose that targeting the molecules that lead to long- lasting changes in the communication between nerve cells in the nucleus accumbens shell could lead to new therapies for smoking cessation.
|Li, Daniel; Musante, Veronica; Zhou, Wenliang et al. (2018) Striatin-1 is a B subunit of protein phosphatase PP2A that regulates dendritic arborization and spine development in striatal neurons. J Biol Chem 293:11179-11194|
|Lewis, Alan S; van Schalkwyk, Gerrit Ian; Lopez, Mayra Ortiz et al. (2018) An Exploratory Trial of Transdermal Nicotine for Aggression and Irritability in Adults with Autism Spectrum Disorder. J Autism Dev Disord 48:2748-2757|
|Calarco, Cali A; Li, Zhiying; Taylor, Seth R et al. (2018) Molecular and cellular characterization of nicotinic acetylcholine receptor subtypes in the arcuate nucleus of the mouse hypothalamus. Eur J Neurosci :|
|Jung, Yonwoo; Lee, Angela M; McKee, Sherry A et al. (2017) Maternal smoking and autism spectrum disorder: meta-analysis with population smoking metrics as moderators. Sci Rep 7:4315|
|Roberts, Walter; Verplaetse, Terril L; Moore, Kelly et al. (2017) Effects of varenicline on alcohol self-administration and craving in drinkers with depressive symptoms. J Psychopharmacol 31:906-914|
|Jung, Yonwoo; Hsieh, Lawrence S; Lee, Angela M et al. (2016) An epigenetic mechanism mediates developmental nicotine effects on neuronal structure and behavior. Nat Neurosci 19:905-14|
|Esterlis, Irina; Hillmer, Ansel T; Bois, Frederic et al. (2016) CHRNA4 and ANKK1 Polymorphisms Influence Smoking-Induced Nicotinic Acetylcholine Receptor Upregulation. Nicotine Tob Res 18:1845-52|
|McClure-Begley, Tristan D; Esterlis, Irina; Stone, Kathryn L et al. (2016) Evaluation of the Nicotinic Acetylcholine Receptor-Associated Proteome at Baseline and Following Nicotine Exposure in Human and Mouse Cortex. eNeuro 3:|
|Lewis, Alan S; Oberleitner, Lindsay M S; Morgan, Peter T et al. (2016) Association of Cigarette Smoking With Interpersonal and Self-Directed Violence in a Large Community-Based Sample. Nicotine Tob Res 18:1456-62|
|Park, Joongkyu; Chávez, Andrés E; Mineur, Yann S et al. (2016) CaMKII Phosphorylation of TARP?-8 Is a Mediator of LTP and Learning and Memory. Neuron 92:75-83|
Showing the most recent 10 out of 77 publications