DIFFERENTIAL GENE EXPRESSION & TOLERANCE TO CANNABINOIDS

长期服用大麻素(德尔塔-9-THC)可导致 L的耐受度，即生理和行为功能恢复到 接近正常(对照)水平，但重要的第二信使通路仍有变化 对细胞机制参与的发展的理解 对长期大麻素治疗的耐受性将提供对治疗过程的洞察 负责对其他经常使用或滥用的药物的耐受性。 对这些过程的调查可以从实施新的 快速检查可能已更改的表达模式的策略 大量的基因，以确定哪些基因可能与 产生容忍度。大规模基因芯片的初步数据 筛选技术显示，有相当数量的基因与 大麻素系统功能的各个方面都表现出变化 在21天的治疗期间的模式。这些模式被分成两个部分进行评估 不同的大脑区域，海马体和小脑，显示出相似的时间 大麻素(CBL)受体和第二信使信号的变化。 假设，共同系统及其各自的分子对应物 可能参与对慢性药物暴露的适应，但这可能在特定的大脑区域和特定的细胞类型之间有所不同。我们建议修改和扩大cDNAs的用途 微阵列进一步描绘基因表达改变的变化 长期接触大麻素。具体目标1将描述 这些脑区和其他3个脑区的差异基因表达模式 在慢性大麻素治疗期间的不同时间点(即天数)。 具体目标2将通过评估以下方面的变化进一步进行分析 慢性催促戒断过程中的基因表达谱 暴露在大麻素中。特定目标3将评估大脑中的特定区域 这些基因表达的变化是利用原位杂交来实现的 确定其表达的基因的区域和细胞分布 在慢性暴露和突然戒断期间发生的变化(具体 目标1和2)。

Chronic administration of cannabinoids (delta 9-THC) result in an unusua l degree of tolerance in which physiological and behavioral functions revert to near normal (control) levels but important second messenger pathways remain altered Understanding of the cellular mechanisms involved in the development of tolerance to chronic cannabinoid treatment will provide insight into processes responsible for tolerance to other frequently administered or abused drugs. Investigation of these processes can benefit from implementation of new strategies to quickly examine potentially altered expression profiles across large numbers of genes in order to determine those that might be involved in producing tolerance. Preliminary data using large scale cDNA microarray screening technology revealed that a significant number of genes related to various aspects of cannabinoid system function showed altered expression patterns across a 21 day treatment period. These patterns were assessed in two different brain regions, hippocampus and cerebellum and revealed similar time courses to cannabinoid (CBl) receptor and second messenger signaling changes. It is hypothesized that, common systems and their respective molecular counterparts may participate in adaptation to chronic drug exposure but this may differ across particular brain regions specific cell types. We propose to adapt and extend use of cDNA microarrays to delineate further the changes in altered gene expression during chronic exposure to cannabinoids. Specific Aim 1 will characterize the differential gene expression patterns in these and 3 other brain regions at different time points (i.e. days) during chronic cannabinoid treatment. Specific Aim 2 will take the analysis one step further by assessing changes in gene expression profiles during precipitated withdrawal from chronic cannabinoid exposure. Specific Aim 3 will assess the specific brain regions in which these gene expression changes occur utilizing in situ hybridization to determine the regional and cellular distribution of genes whose expression is changed during chronic exposure and during precipitated withdrawal (Specific Aims 1 and 2).