摘要篇首： During the last decade, much progress has been made in exploring the mechanisms of alterations elicited by foreign compounds in xeno- and endobiotic metabolism regulated by the human nuclear pregnane X receptor (PXR). PXR, identified as a human nuclear receptor in 1998 and generally regarded as a sensor activated by exogenous and endogenous chemicals,regulates a large number of enzymes and transporters involved in the response of mammals to their chemical environment) PXR activation is ligand dependent.Following ligand binding, PXR forms a heterodimer with the retinoid X receptor (RXR) that binds to PXR response dements, resulting in their transcriptional activation. PXR is mainly associated with the cellular response to xenobiotics, including induction of enzymes involved in drug oxidation and conjugation, as well as induction of xenobiotic and endobiotic transporters. Unlike other nuclear receptors such as the steroid receptors that interact selectively with their physiological ligands, PXR ligands are structurally diverse and include prescription drugs,herbal medicines, dietary supplements, environmental pollutants, and endobiotics. PXR exhibits the ability to bind multiple ligands, and each receptor's ligand specificity is species-dependent. The detailed information of PXR was summarized (Table 1). The purpose of this review is to highlight the promiscuous ligand-binding properties of PXR, its positive effect in regulation of the body's garbage-disposal system and negative effect in harmful drug-drug interactions and endocrine disruption.