Identification and characterization of two novel cannabinoid receptors

描述（由申请人提供）：到1993年，已经确定了两种已知的大麻素受体。从那以后，一个关键问题一直萦绕在大麻素领域：这是所有的大麻素受体，还是还有其他的大麻素受体有待发现？间接证据支持海马体中有多达三种额外的“大麻素”受体，但没有受体被分子识别。如果有可能清楚地识别和分离介导非cb1大麻素反应的神经元，那么利用现有技术识别和克隆受体应该是可能的。克隆一种新的大麻素受体将是大麻素领域的重大发展。在研究培养的自适应海马神经元（DSE）内源性大麻素可塑性的过程中，我已经确定了五个兴奋性神经元亚群，其中两个亚群对大麻素表现出不同的反应，即使在缺乏CB1受体的情况下。由于自适应神经元是孤立的，因此可以提取几乎完整的整个细胞群。因此，我能够在药理学上识别和分离两个神经元亚群的例子，每个亚群都表达不同的非cb1大麻素受体。该建议的具体目的是：1。表征大麻素样反应在两个神经元亚群使用电生理方法。这构成了大部分拟议的实验，并且在很大程度上独立于特定目标#2（但将大大增强）。2. 鉴定两种新型大麻素受体。这将通过从每个亚群中提取和扩增RNA，然后使用基因阵列和候选基因方法克隆受体来完成。发现两种新的大麻素受体将对健康产生重大影响。大麻是一种主要的滥用药物，通过大麻素受体起作用。了解所有大麻素受体的身份和功能是了解大麻如何影响身体的关键。

DESCRIPTION (provided by applicant): By 1993, both known cannabinoid receptors had been identified. Since then, a key question has hovered over the cannabinoid field: is that all there is or do additional cannabinoid receptors remain to be discovered? Indirect evidence supports as many as three additional 'cannabinoid' receptors in the hippocampus, but no receptors have been molecularly identified. If it were possible to clearly identify and isolate a neuron mediating a non-CB1 cannabinoid response, then it should be possible using existing technologies to identify and clone the receptor. The cloning of a novel cannabinoid receptor would be a major development in the cannabinoid field. In the process of studying endocannabinoid plasticity in cultured autaptic hippocampal neurons (DSE) I have identified five subpopulations of excitatory neurons, two of which exhibit distinct responses to cannabinoids, even in the absence of CB1 receptors. Because autaptic neurons are solitary it is possible to extract the entire cell mass nearly intact. Thus I am in a position to pharmacologically identify and isolate examples of two neuronal subpopulations each expressing a distinct non-CB1 cannabinoid receptor. The specific aims of the proposal are to: 1. Characterize the cannabinoid-like response in both neuronal subpopulations using electrophysiological methods. This constitutes the bulk of proposed experiments and is largely independent of (but would be greatly enhanced by) Specific Aim #2. 2. Identify the two novel cannabinoid receptors. This will be done by extracting and amplifying RNA from each subpopulation, and then cloning the receptor using gene array and candidate gene approaches. Discovery of two new cannabinoid receptors would have considerable health implications. Marijuana is a major drug of abuse, acting via cannabinoid receptors. Knowing the identity and function of all cannabinoid receptors is key to understanding how marijuana affects the body.