CELLULAR NEUROBIOLOGY RESEARCH PROJECT

描述（由申请人提供）：本项目建议继续对神经递质及其受体在酒精中毒和成瘾中的作用进行细胞研究，其基本原理是突触是乙醇作用的最敏感部位，特别是由谷氨酸、GABA和神经肽释放介导的突触。我们过去的研究使我们假设“代谢型”受体和突触后NMDA和GABAA受体在乙醇中毒和依赖中的作用。第二个理由是基于行为研究结果，表明扩展杏仁核是包括酒精在内的几种药物成瘾特性的关键系统，并且可能涉及几种递质，神经肽和内源性大麻素。杏仁核与动机行为和焦虑状态有关。应激源和焦虑激发刺激可能会引发人类酗酒者的复发，乙醇戒断与啮齿动物焦虑样行为和乙醇自我管理的增加有关。因此，我们假设，在延长杏仁核的电路内的相同的神经药理学系统介导焦虑状态的增加和在从慢性乙醇戒断期间发生的乙醇自我给药， 我们提出了以下3组细胞研究来检验这一假设：1）检验急性和慢性乙醇给药、早期戒断和长期戒断对中央杏仁核（CeA）神经元CRF效应的影响和相互作用。2)研究急性和慢性乙醇给药、早期戒断和禁欲对CeA神经元中神经肽Y（NPY）作用的影响。3)测试急性和慢性乙醇，早期戒断和禁欲对CeA和NAcc（NAcc）中内源性大麻素作用的影响。在所有3个目标中，受试者将是假手术（对照）雄性大鼠或通过乙醇蒸汽吸入和/或通过自我给药接受慢性乙醇的大鼠，在停药后1- 1 - 2小时或1-2周对它们的CeA或NAcc切片并进行研究。我们将用细胞内（电流和电压灯）记录杏仁核和NAcc脑切片。 和“膜片”全细胞钳方法。红外DIC-视频显微镜方法将是 用于识别形态上不同的细胞类型，以比较电生理和 药理学特性我们将记录诱发的、药理学隔离的单突触电流或电位，以及自发和微型突触事件，以更好地测试乙醇和配体的特异性和作用部位。我们相信，这些研究将提供重要的新信息，在细胞水平上的酒精中毒的可能后遗症，并凭借控制，慢性和长期禁欲模型中的乙醇和肽/大麻素的相互作用的分析，也将提供线索，乙醇依赖的细胞和离子通道相关。

DESCRIPTION (provided by applicant): This project proposes to continue cellular studies of the role of neurotransmitters and their receptors in alcohol intoxication and addiction, with the rationale that the synapse is the most sensitive site of ethanol action, and particularly those synapses mediated by glutamate, GABA, and neuropeptide release. Our past studies led us to hypothesize a role for 'metabotropic' receptors and postsynaptic NMDA and GABAA receptors in ethanol intoxication and dependence. A second rationale is based on behavioral findings suggesting that the extended amygdala is a key system in the addictive properties of several drugs, including alcohol, and that several transmitters, neuropeptides, and endocannabinoids may be involved there. The amygdala has been implicated in motivated behaviors and anxiety states. Stressors and anxiety-provoking stimuli may trigger relapse in human alcoholics, and ethanol withdrawal is associated with increases both in anxiety-like behavior and in ethanol self-administration in rodents. Therefore, we hypothesize that the same neuropharmacological systems within the extended amygdala's circuitry mediate increases in anxiety state and in ethanol self-administration that occur during withdrawal from chronic ethanol, and we propose the following 3 sets of cellular studies to test this hypothesis: 1) Examination of the effects and interactions of acute and chronic ethanol administration, early withdrawal and protracted abstinence on CRF effects in central amygdala (CeA) neurons. 2) Examination of the effects of acute and chronic ethanol administration, early withdrawal and abstinence on neuropeptide Y (NPY) effects in CeA neurons. 3) Testing the effects of acute and chronic ethanol, early withdrawal and abstinence on endocannabinoid effects in CeA and nucleus accumbens (NAcc). In all 3 of these aims, subjects will be sham (control) male rats or those receiving chronic ethanol either via ethanol vapor inhalation and/or via self-administration, and their CeA or NAcc sliced and studied 1-12 hours or 1-2 weeks after withdrawal. We will record from amygdala and NAcc brain slices with intracellular (current- and voltageclamp) and "patch-slice" whole-cell clamp methods. The infrared DIC-videomicroscopic method will be used to identify morphologically distinct cells types for comparison of electrophysiological and pharmacological properties. We will record evoked, pharmacologically-isolated monosynaptic currents or potentials, and spontaneous and miniature synaptic events, to better test the specificity and site of action of ethanol and ligands. We believe these studies will provide important new information on possible sequelae of ethanol intoxication at the cellular level, and, by virtue of analyses of ethanol and peptide/cannabinoid interactions in control, chronic and protracted abstinence models, will also provide clues as to the cellular and ion channel correlates of ethanol dependence.