## Abstract A physiological concentration of extracellular ATP stimulated biphasic Ca^2+^ signal, and the Ca^2+^ transient was decreased and the Ca^2+^ sustain was eliminated immediately after removal of ATP and Ca^2+^ in RBAβ2 astrocytes. Reintroduction of Ca^2+^ induced Ca^2+^ sustain. Stimulatio
Functional characterization of P2Y and P2X receptors in human eosinophils
β Scribed by Marco Idzko; Stefan Dichmann; Elisabeth Panther; Davide Ferrari; Yared Herouy; Christian Virchow; Jr.; Werner Luttmann; Francesco Di Virgilio; Johannes Norgauer
- Publisher
- John Wiley and Sons
- Year
- 2001
- Tongue
- English
- Weight
- 193 KB
- Volume
- 188
- Category
- Article
- ISSN
- 0021-9541
- DOI
- 10.1002/jcp.1129
No coin nor oath required. For personal study only.
β¦ Synopsis
Activation of purinoceptor by ATP induces in eosinophils various cell responses including calcium transients, actin polymerization, production of reactive oxygen metabolites, CD11b-expression, and chemotaxis. Here, the effect of ion channel-gated P2X and/or G protein-coupled P2Y receptor agonists ATP, ATPgammaS, alpha,beta-meATP, 2-MeSATP, BzATP, ADP, CTP, and UTP on the intracellular Ca(2+)-mobilization, actin polymerization, production of reactive oxygen metabolites, CD11b expression and chemotaxis of human eosinophils were measured and the biological activity was analyzed. Although all tested nucleotides were able to induce all these cell responses, the biological activity of the analyzed nucleotides were distinct. Agonists of the G protein-coupled P2Y receptors such as 2-MeSATP, UTP, and ADP have a higher biological activity for production of reactive oxygen metabolites, actin polymerization and chemotaxis in comparison to the ion channel-gated P2X agonists alphabeta-meATP, BzATP, and CTP. In contrast, P2Y and P2X agonist showed similar potencies in respect to intracellular calcium transient and CD11b up-regulation. This conclusion was further supported by experiments with receptor iso-type antagonist KN62, EGTA or with the G(i) protein-inactivating pertussis toxin. These findings indicate participation of different purinorecptors in the regulation of cell responses in eosinophils.
π SIMILAR VOLUMES
Since the identification of a P2X receptor-mediated central synapse in 1992 and the initial cloning of the P2X receptors in 1994 there has been great interest in the possible functions of P2X receptors in the CNS. The purpose of this review is not to detail every study but to highlight recent advanc
## Abstract ATP is the dominant messenger for astrocyteβtoβastrocyte calciumβmediated communication. Definition of the exact ATP/P2 receptors in astrocytes and of their coupling to intracellular calcium ([Ca^2+^]~i~) has important implications for brain physiology and pathology. We show that, with