Advances in research on constitutive activity and inverse agonists of G protein-coupled receptors

G protein-coupled receptors(GPCR)belong to a superfamily of receptors and have numerous members.The activation of GPCR contributes to the most of physiological functions.In recent years,accumulative evidence confirms the occurrence of constitutive activity of GPCR in the absence of agonist stimulation.A new concept of inverse agonists is raised and accepted for some compounds.It can inversely activate GPCR by decreasing the constitutive activity.The new progress in the research on the constitutive activity and inverse agonists of GPCR displays an important significance in application of the receptor theory,and practical values for drug development.