Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
???displayArticle.abstract???
Extracellular adenosine triphosphate (ATP) participates in maintaining the vascular tone in the CNS, particularly in the retina, via the tonic activity of ligand gated activated P2X1 receptors. P2X1 receptors are characterized by their high affinity for ATP and their strong desensitization to concentrations of ATP that are 200-fold lower than their EC50. The mechanism behind P2X1 tonic activity remains unclear. In this study, we expressed human P2X1 (hP2X1) homomeric receptors in Xenopus oocytes to explore the relationship between ATP release from oocytes at rest, hP2X1, and Ca2+-activated Cl- channels. Our results indicate that Xenopus oocytes release ATP at rest via vesicular exocytosis, and this process is a constitutive phenomenon independent of extracellular Ca2+. Our results also indicate that hP2X1 receptors are able to sustain a tonic activity of Ca2+-activated Cl- channels. In the presence of extracellular Ca2+ the activity of hP2X1 receptors is greatly amplified by its coupling with Ca2+-activated Cl- channels. Future studies addressing the relationship between hP2X1 receptors and Ca2+-activated Cl- channels in vascular smooth muscle cells should provide information about additional mechanisms that regulate the vascular tone and their potential as pharmaceutical targets. This article is part of a Special Issue entitled: Honoring Ricardo Miledi - outstanding neuroscientist of XX-XXI centuries.
Aleu,
Release of ATP induced by hypertonic solutions in Xenopus oocytes.
2003, Pubmed,
Xenbase
Aleu,
Release of ATP induced by hypertonic solutions in Xenopus oocytes.
2003,
Pubmed
,
Xenbase
Arellano,
Novel Cl- currents elicited by follicle stimulating hormone and acetylcholine in follicle-enclosed Xenopus oocytes.
1993,
Pubmed
,
Xenbase
Arellano,
Functional interaction between native G protein-coupled purinergic receptors in Xenopus follicles.
2009,
Pubmed
,
Xenbase
Bahima,
Endogenous hemichannels play a role in the release of ATP from Xenopus oocytes.
2006,
Pubmed
,
Xenbase
Berridge,
Caffeine inhibits inositol-trisphosphate-induced membrane potential oscillations in Xenopus oocytes.
1991,
Pubmed
,
Xenbase
Bodas,
ATP crossing the cell plasma membrane generates an ionic current in xenopus oocytes.
2000,
Pubmed
,
Xenbase
Bulley,
TMEM16A/ANO1 channels contribute to the myogenic response in cerebral arteries.
2012,
Pubmed
Burnstock,
Purinergic signalling: from discovery to current developments.
2014,
Pubmed
Evans,
Ionic permeability of, and divalent cation effects on, two ATP-gated cation channels (P2X receptors) expressed in mammalian cells.
1996,
Pubmed
Fabbro,
Quantal release of ATP from clusters of PC12 cells.
2004,
Pubmed
Fields,
ATP: an extracellular signaling molecule between neurons and glia.
2000,
Pubmed
Grote,
Nanomolar ambient ATP decelerates P2X3 receptor kinetics.
2008,
Pubmed
Heinze,
Disruption of vascular Ca2+-activated chloride currents lowers blood pressure.
2014,
Pubmed
Hollins,
Heterologous expression of a P2x-purinoceptor in rat chromaffin cells detects vesicular ATP release.
1997,
Pubmed
Jin,
Activation of the Cl- channel ANO1 by localized calcium signals in nociceptive sensory neurons requires coupling with the IP3 receptor.
2013,
Pubmed
Kur,
Purinergic control of vascular tone in the retina.
2014,
Pubmed
Kusano,
Cholinergic and catecholaminergic receptors in the Xenopus oocyte membrane.
1982,
Pubmed
,
Xenbase
Lazarowski,
Vesicular and conductive mechanisms of nucleotide release.
2012,
Pubmed
Limon,
Dipicrylamine Modulates GABAρ1 Receptors through Interactions with Residues in the TM4 and Cys-Loop Domains.
2016,
Pubmed
,
Xenbase
Lohman,
Mechanisms of ATP release and signalling in the blood vessel wall.
2012,
Pubmed
Maroto,
Brefeldin A block of integrin-dependent mechanosensitive ATP release from Xenopus oocytes reveals a novel mechanism of mechanotransduction.
2001,
Pubmed
,
Xenbase
McDonald,
Potent desensitization of human P2X3 receptors by diadenosine polyphosphates.
2002,
Pubmed
,
Xenbase
Miledi,
Effects of defolliculation on membrane current responses of Xenopus oocytes.
1989,
Pubmed
,
Xenbase
Miledi,
Chloride current induced by injection of calcium into Xenopus oocytes.
1984,
Pubmed
,
Xenbase
Miledi,
A calcium-dependent transient outward current in Xenopus laevis oocytes.
1982,
Pubmed
,
Xenbase
Nakamura,
P2Y1 purinergic receptors in sensory neurons: contribution to touch-induced impulse generation.
1996,
Pubmed
,
Xenbase
Ni,
Activation and inhibition of TMEM16A calcium-activated chloride channels.
2014,
Pubmed
Oh,
Development of selective blockers for Ca²(+)-activated Cl channel using Xenopus laevis oocytes with an improved drug screening strategy.
2008,
Pubmed
,
Xenbase
Praetorius,
ATP release from non-excitable cells.
2009,
Pubmed
Rettinger,
Desensitization masks nanomolar potency of ATP for the P2X1 receptor.
2004,
Pubmed
,
Xenbase
Rettinger,
Activation and desensitization of the recombinant P2X1 receptor at nanomolar ATP concentrations.
2003,
Pubmed
,
Xenbase
Saldaña,
Native ion current coupled to purinergic activation via basal and mechanically induced ATP release in Xenopus follicles.
2009,
Pubmed
,
Xenbase
Saldaña,
Epithelium and/or theca are required for ATP-elicited K+ current in follicle-enclosed Xenopus oocytes.
2005,
Pubmed
,
Xenbase
Samways,
Principles and properties of ion flow in P2X receptors.
2014,
Pubmed
Shuai,
The number and spatial distribution of IP3 receptors underlying calcium puffs in Xenopus oocytes.
2006,
Pubmed
,
Xenbase
Soto,
Antagonistic properties of the suramin analogue NF023 at heterologously expressed P2X receptors.
1999,
Pubmed
,
Xenbase
Tigyi,
A serum factor that activates the phosphatidylinositol phosphate signaling system in Xenopus oocytes.
1990,
Pubmed
,
Xenbase
Valera,
A new class of ligand-gated ion channel defined by P2x receptor for extracellular ATP.
1994,
Pubmed
,
Xenbase
Vial,
Differential sensitivity of human platelet P2X1 and P2Y1 receptors to disruption of lipid rafts.
2006,
Pubmed
Zampighi,
Functional and morphological correlates of connexin50 expressed in Xenopus laevis oocytes.
1999,
Pubmed
,
Xenbase
Zampighi,
A method for determining the unitary functional capacity of cloned channels and transporters expressed in Xenopus laevis oocytes.
1995,
Pubmed
,
Xenbase
