IN VITRO MODELS FOR ETHANOL EFFECTS ON RECEPTORS

我们工作的一个主要重点是评估急性和 酒精对中枢神经系统的慢性影响。 然而，大脑 表示细胞类型的异质集合，并且 乙醇的直接和间接影响的区别， 难 我们正在开发体外器官和组织培养 可用于监测特定的直接影响的系统 乙醇，用于与 脑组织和体内。 我们培养了一种 小脑颗粒细胞，其中β-肾上腺素能受体和 可以测量激动剂刺激的环AMP产生; 神经胶质和神经元成分在这些反应中的作用正在被研究， 分析了 刺激小脑环鸟苷酸的产生 颗粒细胞也在测定中。 乙醇似乎抑制了 这种刺激，类似于大脑中报告的结果。 乙醇 增强异丙肾上腺素刺激的环磷酸腺苷和褪黑激素 在培养中由松果体产生。 这些发现增强了 受体-效应器偶联与我们报道的相似 在某些大脑区域，并允许和调查的影响， 乙醇对受体的生理后果 activation. 乙醇似乎也能增强环磷酸腺苷 在嗜铬细胞瘤（PC 12）细胞中产生，这些细胞是 其特征在于刺激环AMP 产生血管活性肠肽，腺苷和 毛喉素 在PC 12细胞中，我们还发现， 浓度的乙醇（25 mM）抑制毒蕈碱-和 去极化诱导的去甲肾上腺素释放。 在前 在这种情况下，乙醇似乎调节毒蕈碱刺激的肌醇 三磷酸盐的产生，从而钙的动员。 这些系统允许对现场进行详细检查， 乙醇的作用机制和生物化学的变化 在体内可能与乙醇耐受性相关的系统 身体依赖。

A major focus of our work involves an evaluation of the acute and chronic effects of ethanol in the CNS. However, the brain represents a heterogeneous collection of cell types, and distinction of direct and indirect effects of ethanol can be difficult. We are developing in vitro organ and tissue culture systems that can be used to monitor specific, direct effects of ethanol, for comparison and contrast with results obtained in brain tissue and in vivo. We have developed a primary culture of cerebellar granule cells in which beta-adrenergic receptors and agonist-stimulated cyclic AMP production can be measured; the role of glial and neuronal elements in these responses is being analyzed. Stimulation of cyclic GMP production in cerebellar granule cells is also being determined. Ethanol appears to inhibit this stimulation, similar to results reported in brain. Ethanol enhances isoproterenol-stimulated cyclic AMP and melatonin production by pineal glands in culture. These findings of enhanced receptor-effector coupling are similar to what we have reported in certain brain areas, and allow and investigation of the effects of ethanol on the physiological consequences of receptor activation. Ethanol also appears to enhance cyclic AMP production in pheochromocytoma (PC12) cells, and these cells are being characterized with respect to stimulation of cyclic AMP production by vasoative intestinal peptide, adenosine and forskolin. In PC12 cells, we have also found that low concentrations of ethanol (25mM) inhibit muscarine- and depolarization-induced norepinephrine release. In the former case, ethanol appears to modulate muscarine-stimulated inositol trisphosphate production, and therefore calcium mobilization. These systems allow for detailed examination of the sites and mechanisms of action of ethanol and of changes in biochemical systems that may, in vivo, be associated with ethanol tolerance and physical dependence.