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NIDA - Director's Report - September, 2009 NIDA Home > Publications > Director's Reports Director's Report to the National Advisory Council on Drug Abuse - September, 2009 Index Research Findings Multi-Division Research Basic Neurosciences Research Basic Behavioral Research Behavioral and Brain Development Research Clinical Neuroscience Research Epidemiology and Etiology Research Prevention Research Research on Behavioral and Combined Treatments for Drug Abuse Research on Pharmacotherapies for Drug Abuse Research on Medical Consequences of Drug Abuse and Co-Occurring Infections (HIV/AIDS, HCV) Services Research Clinical Trials Network Research International Research Intramural Research Program Activities Extramural Policy and Review Activities Congressional Affairs International Activities Meetings and Conferences Media and Education Activities Planned Meetings Publications Staff Highlights Grantee Honors https://archives.drugabuse.gov/DirReports/DirRep909/Default.html[11/17/16, 11:20:48 PM] NIDA - Director's Report - September, 2009 Archive Home | Accessibility | Privacy | FOIA (NIH) | Current NIDA Home Page The National Institute on Drug Abuse (NIDA) is part of the National Institutes of Health (NIH) , a component of the U.S. Department of Health and Human Services. Questions? _ See our Contact Information. https://archives.drugabuse.gov/DirReports/DirRep909/Default.html[11/17/16, 11:20:48 PM] NIDA - Director's Report - September, 2009 NIDA Home > Publications > Director's Reports > September, 2009 Index Director's Report to the National Advisory Council on Drug Abuse - September, 2009 Index Research Findings - Basic Neuroscience Research Research Findings Toll-Like Receptor-3 Activation in Human Neuronal Cells Induces Basic Neurosciences Interferon-λ Expression Research Basic Behavioral Research Interferon lambda (IFN-λ) belongs to the type III family of IFNs which when activated exerts antiviral, antitumor and immunoregulatory activities. Toll-like Behavioral and Brain receptors (TLRs) are a family of receptors that mediate innate immune Development Research responses to stimuli from pathogens and endogenous signals. It has been Clinical Neuroscience shown that agonists of TLR-3 can induce IFN-λ production in macrophages or Research plasmacytoid dendritic cells. Little is known about IFN-λ expression in human Epidemiology and Etiology neuronal cells and whether IFN-λ expression in human neuron relies on the TLR Research ligand activation. Human neuronal cells expressed endogenous IFN-λ1, but not IFNλ2/3, however upon activation of TLR-3 in neuronal cells all three Prevention Research structurally related cytokines were significantly induced. Activation of TLR-3 Research on Behavioral and also exhibited antiviral activity against pseudotyped HIV-1 infection of the Combined Treatments for neuronal cells. Human neuronal cells also expressed functional IFN-λ receptors Drug Abuse which when activated inhibited pseudotyped HIV-1 infection and induced Research on APOBEC 3G/3F, anti-HIV-1 cellular factors. This paper provides compelling Pharmacotherapies for Drug evidence that there is intracellular expression and regulation of IFN-λ in human Abuse neuronal cells, which may have a major role in the innate neuronal protection Research on Medical against viral infections in the CNS. Zhou L, Wang X, Wang YJ, Zhou Y, Hu S, Ye Consequences of Drug L, Hou W, Li H, Ho WZ. Activation of Toll-Like receptor-3 induces interferon-λ Abuse and Co-Occurring expression in human neuronal cells. Neuroscience. 2009 Mar 17;159(2):629- Infections (HIV/AIDS, HCV) 637. Services Research Chronic Cocaine Enhances Stress-Induced Potentiation of Clinical Trials Network Excitatory (Glutamatergic) Neurotransmission in Dopamine Research Neurons within the VTA International Research Intramural Research Current concepts suggest that stress-induced release of neuromodulators such as corticotropin-releasing factor (CRF) can drive drug-dependent behaviors. Program Activities Furthermore, prior drug exposure can enhance behavioral and neurochemical responses to stress. Previously, it had been shown that CRF can enhance Extramural Policy and NMDA-type glutamatergic transmission. This paper now shows that after Review Activities repeated cocaine exposure, the magnitude and duration of the CRF-induced potentiation of NMDA receptor-mediated neurotransmission is significantly Congressional Affairs increased within ventral tegmental area (VTA) dopamine neurons, a key locus of drug- and stress-induced neuroadaptation. Furthermore, although CRF itself International Activities does not enhance AMPA-type glutamatergic transmission, CRF did enhance AMPA receptor-mediated transmission in mice that were exposed to chronic Meetings and Conferences cocaine. Importantly, pharmacological experiments revealed that CRF receptor 1 and protein kinase A pathways were newly recruited after repeated cocaine Media and Education for the enhancement of CRF-induced NMDAR potentiation and the appearance Activities of AMPAR potentiation. Thus, enhanced CRF-induced potentiation of excitatory https://archives.drugabuse.gov/DirReports/DirRep909/DirectorReport1.html[11/17/16, 11:20:52 PM] NIDA - Director's Report - September, 2009 synaptic transmission onto VTA dopamine neurons after cocaine preexposure is Planned Meetings likely to produce an abnormal increase in dopamine release during stressful events and could augment activation of addictive behaviors in response to Publications stress. Hahn J, Hopf FW, Bonci A. Chronic cocaine enhances corticotropin- releasing factor-dependent potentiation of excitatory transmission in ventral Staff Highlights tegmental area dopamine neurons. J Neurosci. 2009 May 20;29(20):6535- 6544. Grantee Honors Impaired Synaptic Plasticity Following Chronic Cocaine Dr. Peter Kalivas and colleagues have been providing novel evidence that chronic drug abuse results in future deficits in the ability to generate synaptic plasticity (for review, see Kalivas PW. Nat Rev Neurosci. 2009 Aug;10(8):561- 572). In the present study, his group sought to determine whether withdrawal from repeated cocaine administration can alter the capacity of a subsequent cocaine injection to elicit morphological, biochemical, and physiological plasticity. Three weeks after termination of chronic daily cocaine or saline administration, the researchers filled neurons in the nucleus accumbens with the lipophilic dye, DiI. They observed a shift to larger diameter spines in the daily cocaine-pretreated rats. During the first 2 hours after an acute cocaine challenge, a bidirectional change in spine head diameter and increase in spine density was measured in the daily cocaine-pretreated animals. In contrast, no change in spine diameter or density was elicited by a cocaine challenge in daily saline animals during the first 2 hours after injection. However, spine density was elevated at 6 hours after a cocaine challenge in daily saline-pretreated animals. The time-dependent profile of proteins in the postsynaptic density subfraction of neurons elicited by a cocaine challenge in daily cocaine- pretreated subjects indicated that the changes in spine diameter and density were associated with a deteriorating actin cytoskeleton and a reduction in glutamate signaling-related proteins. Correspondingly, the amplitude of field potentials in accumbens evoked by stimulating prefrontal cortex was reduced for up to 6 hours after acute cocaine in daily cocaine-withdrawn animals. These data indicate that daily cocaine pretreatment dysregulates dendritic spine plasticity elicited by a subsequent cocaine injection. In humans, the altered drug experience caused by previous drug abuse may underlie diminishing behavioral control and contribute to a progressively deteriorating disorder. Shen H, Toda S, Moussawi K, Bouknight A, Zahm DS, Kalivas PW. Altered dendritic spine plasticity in cocaine-withdrawn rats. J Neurosci. 2009 Mar 4;29(9):2876-2884. Optical Fluorescent Tool Monitors Dopamine Release From Single Presynaptic Terminals Investigators at Columbia University have designed optical tracers of monoaminergic neuro-transmitters, or false fluorescent neurotransmitters, which are taken up by secretory vesicles (VMAT2) and released after stimulation as if they were native transmitters. This has allowed the researchers to examine transmitter accumulation and exocytosis from single presynaptic terminals in the striatum and to make observations relevant to stimulation-dependent synaptic plasticity. They found a relatively low percentage of vesicles fusing to the plasma membrane with each stimulus, and that the release of transmitter differed across separate terminals. That is, some terminals were more active than others; additionally, transmitter release from each terminal also depended on the frequency of stimulation. Further, when the presynaptic autoreceptors on neurons were blocked, release was inhibited from two-thirds of the terminals, which were the terminals that were least active. Thus, activity-dependent terminal heterogeneity is associated with receptor-mediated responses and underscores the presence of frequency- dependent coding that may determine how particular synapses are activated during important functions such as decision-making and learning. Gubernator https://archives.drugabuse.gov/DirReports/DirRep909/DirectorReport1.html[11/17/16, 11:20:52 PM] NIDA - Director's Report - September, 2009 NG, Zhang H, Staal RGW, Mosharov EV, Pereira DB, Yue M, Balsanek V, Vadola PA, Mukerjee B, Edwards RH, Sulzer D, Sames