Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
EARLY ACTION-POTENTIAL SHORTENING IN HYPOXIC HEARTS - ROLE OF CHLORIDE CURRENT(S) MEDIATED BY CATECHOLAMINE RELEASE
Autore:
PETRICH ER; ZUMINO AP; SCHANNE OF;
Indirizzi:
UNIV SHERBROOKE,FAC MED,DEPT PHYSIOL & BIOPHYS SHERBROOKE PQ J1H 5N4 CANADA
Titolo Testata:
Journal of Molecular and Cellular Cardiology
fascicolo: 2, volume: 28, anno: 1996,
pagine: 279 - 290
SICI:
0022-2828(1996)28:2<279:EASIHH>2.0.ZU;2-S
Fonte:
ISI
Lingua:
ENG
Soggetto:
PIG VENTRICULAR MYOCYTES; TRANSIENT OUTWARD CURRENT; SENSITIVE K+ CHANNELS; CARDIAC MYOCYTES; METABOLIC INHIBITION; CONTRACTILE FAILURE; RABBIT MYOCARDIUM; ATP; MODULATION; TIME;
Keywords:
HYPOXIA; ACTION POTENTIAL SHORTENING; CHLORIDE CURRENTS; ANION TRANSPORT BLOCKERS; ENDOGENOUS CATECHOLAMINE RELEASE;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
51
Recensione:
Indirizzi per estratti:
Citazione:
E.R. Petrich et al., "EARLY ACTION-POTENTIAL SHORTENING IN HYPOXIC HEARTS - ROLE OF CHLORIDE CURRENT(S) MEDIATED BY CATECHOLAMINE RELEASE", Journal of Molecular and Cellular Cardiology, 28(2), 1996, pp. 279-290

Abstract

We tested the hypothesis that the early action potential shortening induced by hypoxia in perfused hearts is attributable to chloride currents activated or modulated by endogenous catecholamine release, Rabbithearts perfused at 33 degrees C and paced at 2.5-2.8 Hz were used formembrane potential recordings with microelectrodes. Catecholamine depletion was induced with reserpine treatment. The effects of nadolol (10 mu M), the stilbenedisulfonic acid derivatives DIDS (10 mu M) and SITS (1 mM), and diphenylamine-2 carboxylate (DPC, 100 mu M) on action potential characteristics were determined at different times during hypoxia, The effect of chloride transport blockers on the outward currents induced by 200 nM carbonyl cyanide (CCCP) or by 1 mu M isoproterenolin isolated cells was also tested, In control hearts, action potential duration (APD) at 25 and 95% repolarization decreased by 50 +/- 9% and 32 + 7% respectively after 5 min of hypoxia, This effect was fully antagonized by reserpine pretreatment, by respiratory acidosis, and bynadolol when present from the beginning of hypoxia. None of these agents affected action potential characteristics in normoxia and nadolol had no effect when added after 15 min of hypoxia. Lowering the chloride concentration to 17.5 mM reproduced the effects of nadolol and reserpine, DIDS and SITS lengthened APD in normoxia and attenuated the early APD shortening in hypoxia. DPC had no effect in normoxia but fully counteracted APD shortening produced by isoproterenol or early hypoxia,In isolated cells, DIDS did not affect the glibenclamide sensitive outward current induced by CCCP and DPC blocked the isoproterenol induced current, The data suggest that in whole hearts, chloride currents mediated by endogenous catecholamine release are involved in the early action potential shortening induced by hypoxia with preservation of glycolysis. (C) 1996 Academic Press Limited

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 05/12/20 alle ore 20:08:57