反向激动剂的特性和研究进展
The characteristics and research progress of inverse agonists

摘要：反向激动剂是一种新的作用于受体的药物类型，其研究经历了β-卡波啉乙酯的发现、活性研究、概念的提出、二态模型、固有活性几个阶段。多数G蛋白耦联受体具有固有活性，在无激动剂时，部分受体处于活化状态，能主动产生效应。反向激动剂对受体有亲和力，无内在活性，不激动受体，但能拮抗受体的固有活性，产生与激动剂相反的效应。反向激动剂和激动剂均能产生效应，但机制不同，激动剂激动受体，反向激动剂拮抗受体；反向激动剂和拮抗剂均拮抗受体，但反向激动剂拮抗受体的固有活性，而拮抗剂拮抗激动剂的效应。反向激动剂可以治疗受体固有活性增强性疾病，可上调和增敏固有活性受体，内源性反向激动剂可维持特定的生理功能。反向激动剂的研究对于完善受体学说有重要的理论意义，对于固有活性增强性疾病的诊断和治疗具有重要的临床意义。
ABSTRACT: Inverse agonist is a new type of drug acting on receptors. Its research has experienced several stages, including discovery of ethyl β-carboline 3-carboxylate, activity study, proposal of the concept, two-state model, and constitutive activity theory in succession. Most G protein-coupled receptors possess constitutive activity, i.e. a proportion of receptors are in active state and can produce effects without any agonist.Inverse agonist has an affinity to receptors, but no intrinsic activity, so it cannot activate receptors. However, it can antagonize the constitutive activity of receptors, and produce an opposite effect on the corresponding agonist. Both agonist and inverse agonist can produce their effect alone with different mechanisms. Agonist activates its receptors, but inverse agonist antagonizes them. Both inverse agonist and antagonist can antagonize receptors. However, inverse agonist and antagonist antagonize the constitutive activity of receptor and the agonist’s effects, respectively. Inverse agonists can be used to treat diseases with enhanced constitutive activity, up-regulate and sensitize receptors with constitutive activity. Moreover, endogenous inverse agonists can maintain a specific physiological function. The study on inverse agonist has a theoretical significance in perfecting receptor theory as well as a clinical value in diagnosis and treatment of diseases with enhanced constitutive activity