Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Two different ionotropic receptors are activated by ATP in rat microglia
Autore:
Visentin, S; Renzi, M; Frank, C; Greco, A; Levi, G;
Indirizzi:
Ist Super Sanita, Lab Pathophysiol, I-00161 Rome, Italy Ist Super Sanita Rome Italy I-00161 ab Pathophysiol, I-00161 Rome, Italy Ist Super Sanita, Pharmacol Lab, I-00161 Rome, Italy Ist Super Sanita Rome Italy I-00161 , Pharmacol Lab, I-00161 Rome, Italy
Titolo Testata:
JOURNAL OF PHYSIOLOGY-LONDON
fascicolo: 3, volume: 519, anno: 1999,
pagine: 723 - 736
SICI:
0022-3751(19990901)519:3<723:TDIRAA>2.0.ZU;2-M
Fonte:
ISI
Lingua:
ENG
Soggetto:
EXTRACELLULAR ATP; PLASMA-MEMBRANE; MOUSE-BRAIN; CELLS; CHANNELS; PURINOCEPTOR; P2X(7); MACROPHAGES; MODULATION; MECHANISMS;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
38
Recensione:
Indirizzi per estratti:
Indirizzo: Visentin, S Ist Super Sanita, Lab Pathophysiol, Viale Regina Elena 299, I-00161 Rome, Italy Ist Super Sanita Viale Regina Elena 299 Rome Italy I-00161 ly
Citazione:
S. Visentin et al., "Two different ionotropic receptors are activated by ATP in rat microglia", J PHYSL LON, 519(3), 1999, pp. 723-736

Abstract

1. Our aim was to assess whether ATP-induced inward currents in microglia are due to a single or more than one purinergic receptor. The ATP dose-response curve showed two components, whose presence might be due to the activation of high and low affinity receptors.2. The P2Z/P2X7 specific receptor agonist benzoylbenzoyl-ATP (Bz-ATP) and some P2 receptor agonists were tested. The rank order of potency was Bz-ATP>> ATP = 8-methylthio-ATP (2-MeSATP) > alpha,beta-methylene ATP (alpha,beta-meATP) greater than or equal to ADP. beta,gamma-MethyleneATP (beta,gamma-meATP), UTP and adenosine were ineffective.3. The non-specific P2 receptor antagonist suramin antagonized by 92 +/- 2% the inward current induced by 100 mu M ATP, and by 51 +/- 8 and 68 +/- 6%those induced by 3 mM ATP and 100 mu M Bz-ATP, respectively. The P2Z/P2X7 antagonist oxidized ATP (oATP) almost abolished the inward current induced by 3 mw ATP or Bz-ATP, but was ineffective against 100 mu M ATP.4. Inward currents induced by low ATP concentrations (less than or equal to 100 mu M) were generally followed by an almost complete and irreversible desensitization, while those elicited by ATP greater than or equal to 1 mM showed only a partial decline. Interestingly,, the inward current induced by 100 mu M 2-MeSATP showed a large desensitization, while that induced by Bz-ATP did not.5. In voltage-ramp experiments, the 100 mu M ATP-induced current exhibiteda slight inward rectification more risible at negative potentials, while the 3 mM ATP-induced current did not.6. ATP induced a fast and large increase in [Ca2+] that promptly recoveredin the continuous presence of low ATP doses, but did not recover in high ATP doses. As with desensitization, the response to Bz-ATP mimicked that of high doses of ATP.7. When Ca2+ mobilization due to P2Y receptors was blocked by thapsigargin-induced Ca2+ depletion or by pertussis toxin treatment, 10 mu M nl ATP wasstill able to induce a Ca2+ transient, which represented the contribution of the Ca2+ influx induced by P2X receptors.8. In conclusion, the inward currents and a fraction of the Ca2+ transients induced by ATP in microglia are due to at least two ATP-sensitive receptor channel types, whose different proper ties and sensitivity to ATP may be associated with different functional roles.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 28/11/20 alle ore 08:41:09