William Paterson University, Wayne NJ and Molecular Neurobiology Branch, National Institute on Drug Abuse, NIH, Baltimore, USA.
Curr Neuropharmacol. 2011 Mar;9(1):205-8. doi: 10.2174/157015911795017416.
Cannabinoids are the constituents of the marijuana plant (Cannabis sativa). There are numerous cannabinoids and other natural compounds that have been reported in the cannabis plant. The recent progress in marijuana-cannabinoid research include the discovery of an endocannabinoid system with specific genes coding for cannabinoid receptors (CBRs) that are activated by smoking marijuana, and that the human body and brain makes its own marijuana-like substances called endocannabinoids that also activate CBRs. This new knowledge and progress about cannabinoids and endocannabinoids indicate that a balanced level of endocannabinoids is important for pregnancy and that the breast milk in animals and humans has endocannabinoids for the growth and development of the new born. There are two well characterized cannabinoid receptors termed CB1-Rs and CB2-Rs and these CBRs are perhaps the most abundant G-protein coupled receptors that are expressed at high levels in many regions of the mammalian brain. The expression of CB1-Rs in the brain and periphery and the identification of CB2-Rs in immune cells and during inflammation has been extensively studied and characterized. However, the expression of functional neuronal CB2-Rs in the CNS has been much less well established and characterized in comparison to the expression of abundant brain CB1-Rs and functional neuronal CB2-Rs has ignited debate and controversy. While the issue of the specificity of CB2-R antibodies remains, many recent studies have reported the discovery and functional characterization of functional neuronal CB2-Rs in the CNS beyond neuro-immuno cannabinoid activity.
大麻素是大麻植物（Cannabis sativa）的组成部分。大麻植物中已经报道了许多大麻素和其他天然化合物。最近在大麻素研究方面的进展包括发现了一个内源性大麻素系统，该系统具有特定的基因，可编码大麻素受体（CBRs），这些受体可被吸食大麻激活，并且人体和大脑会产生自身类似大麻的物质，称为内源性大麻素，也可激活 CBRs。关于大麻素和内源性大麻素的这些新知识和进展表明，内源性大麻素的平衡水平对妊娠很重要，并且动物和人类的母乳中含有内源性大麻素，以促进新生儿的生长和发育。有两种特征明确的大麻素受体，称为 CB1-Rs 和 CB2-Rs，这些 CBRs 可能是表达水平最高的 G 蛋白偶联受体之一，在哺乳动物大脑的许多区域都有高表达。CB1-Rs 在大脑和外周组织中的表达，以及 CB2-Rs 在免疫细胞和炎症期间的表达，已经得到了广泛的研究和描述。然而，与在大脑中丰富表达的 CB1-Rs 相比，功能性神经元 CB2-Rs 在中枢神经系统中的表达和功能特性的研究还远不充分，并且功能性神经元 CB2-Rs 的表达引发了争议。尽管 CB2-R 抗体的特异性问题仍然存在，但许多最近的研究报告了在中枢神经系统中发现和功能性表征功能性神经元 CB2-Rs 的情况，而不仅仅是神经免疫大麻素活性。
