title: Renal P2 receptors and hypertension.
abstract: The regulation of extracellular fluid volume is a key component of blood pressure homeostasis. Long-term blood pressure is stabilized by the acute pressure natriuresis response by which changes in renal perfusion pressure evoke corresponding changes in renal sodium excretion. A wealth of experimental evidence suggests that a defect in the pressure natriuresis response contributes to the development and maintenance of hypertension. The mechanisms underlying the relationship between renal perfusion pressure and sodium excretion are incompletely understood. Increased blood flow through the vasa recta increases renal interstitial hydrostatic pressure, thereby reducing the driving force for transepithelial sodium reabsorption. Paracrine signalling also contributes to the overall natriuretic response by inhibiting tubular sodium reabsorption in several nephron segments. In this brief review, we discuss the role of purinergic signalling in the renal control of blood pressure. ATP is released from renal tubule and vascular cells in response to increased flow and can activate P2 receptor subtypes expressed in both epithelial and vascular endothelial/smooth muscle cells. In concert, these effects integrate the vascular and tubular responses to increased perfusion pressure and targeting P2 receptors, particularly P2X7, may prove beneficial for treatment of hypertension.
authors.affiliation: University/British Heart Foundation, Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK; MRC Institute for Genetics and Molecular Medicine, The University of Edinburgh, Edinburgh, UK.
authors.forename: R I
authors.initials: RI
authors.lastname: Menzies
authors.forename: R J
authors.initials: RJ
authors.lastname: Unwin
authors.forename: M A
authors.initials: MA
authors.lastname: Bailey
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology*; D006801:Humans; D006973:Hypertension / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism*; D018048:Receptors, Purinergic P2 / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*
chemical_list: D018048:Receptors, Purinergic P2
keywords: P2X4; P2X7; inflammation; kidney disease; macrophage; vascular tone