儿茶酚胺类通过与靶细胞膜表面的特异肾上腺素受体相互作用而发挥效应。按其对不同肾上腺素能激动剂和颉抗剂的敏感性的差异,可将这类受体分成两类:α和β受体。α受体又进一步分为α_1和α_2受体。传统上,这种亚分类是根据解剖学观点作出的,即α_2位于突触前膜,α_1位于突触后膜。但这种分法已不再正确,尤其对CNS以外的组织而言。在这些组织中,按其药理特点对α受体进行分类可能更为有用。至今,鉴别α_1 Catecholamines exert their effect by interacting with specific adrenergic receptors on the surface of the target cell membrane. Depending on their sensitivity to different adrenergic agonists and antagonists, these receptors fall into two categories: alpha and beta receptors. Alpha receptors are further divided into alpha 1 and alpha 2 receptors. Traditionally, this sub-classification is based on the anatomical point of view that α_2 is located at the presynaptic membrane and α_1 is located at the postsynaptic membrane. However, this method is no longer correct, especially for organizations other than CNS. In these organizations, classification of alpha receptors by their pharmacological traits may be more useful. So far, identify α_1