Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
The importance of glycolytically-derived ATP for the Na+/H+ exchange activity in guinea pig ventricular myocytes
Autore:
Sugiyama, S; Satoh, H; Nomura, N; Watanabe, H; Hayashi, H;
Indirizzi:
Hamamatsu Univ, Sch Med, Div Cardiovasc Dis, Hamamatsu, Shizuoka 4313192, Japan Hamamatsu Univ Hamamatsu Shizuoka Japan 4313192 , Shizuoka 4313192, Japan Hamamatsu Univ, Sch Med, Div Pharmacol & Therapeut, Hamamatsu, Shizuoka 4313192, Japan Hamamatsu Univ Hamamatsu Shizuoka Japan 4313192 , Shizuoka 4313192, Japan
Titolo Testata:
MOLECULAR AND CELLULAR BIOCHEMISTRY
fascicolo: 1-2, volume: 217, anno: 2001,
pagine: 153 - 161
SICI:
0300-8177(200101)217:1-2<153:TIOGAF>2.0.ZU;2-Z
Fonte:
ISI
Lingua:
ENG
Soggetto:
CARDIAC PURKINJE-FIBER; CYTOSOLIC FREE MAGNESIUM; ISCHEMIC RAT-HEART; H+ BUFFERING POWER; FLUORESCENT INDICATOR; INTRACELLULAR PH; POSSIBLE INVOLVEMENT; NA+-CA2+ EXCHANGE; CYTOPLASMIC ATP; GROWTH-FACTORS;
Keywords:
myocytes; Na+/H+ exchange; glycolysis; oxidative phosphorylation; intracellular acidosis;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
44
Recensione:
Indirizzi per estratti:
Indirizzo: Satoh, H Hamamatsu Univ, Sch Med, Div Cardiovasc Dis, 3600 Handa Cho, Hamamatsu, Shizuoka 4313192, Japan Hamamatsu Univ 3600 Handa Cho Hamamatsu Shizuoka Japan 4313192 an
Citazione:
S. Sugiyama et al., "The importance of glycolytically-derived ATP for the Na+/H+ exchange activity in guinea pig ventricular myocytes", MOL C BIOCH, 217(1-2), 2001, pp. 153-161

Abstract

The cardiac subtype of Na+/H+ exchanger (NHE-1) plays an important role inthe regulation of intracellular pH (pH(i)) and also can be a major route for Na+ influx. Although intracellular ATP is required for the optimal function of NHE-1, the regulation of the exchanger by ATP is less well characterized. This study was designed to investigate which intracellular ATP generated by oxidative phosphorylation or by glycolysis is dominant for the activation of NHE-1 in intact cardiac myocytes. Isolated guinea pig ventricular myocytes were loaded with the pH(i)-sensitive fluorescent indicator, 2'-7'-bis(carboxyl)-5',6'-carboxy fluorescein (BCECF), and exposed to 20 mM 2-deoxyglucose (2-DG) or 2 mM sodium cyanide (CN) to inhibit glycolysis or oxidative phosphorylation, respectively. The activity of NHE-1 was estimated with pHi recovery following transient application of 15 mM NH4Cl (NH4Cl prepulse). After the NH4Cl prepulse, pH(i) decreased from 7.00 +/- 0.03 (mean +/-S.E.) to 6.60 +/- 0.06 and recovered to 6.94 +/- 0.13 at 10 min (n = 7). The pH(i) recovery was suppressed in the presence of 2-DG (6.67 +/- 0.05, p < 0.01, n = 7), but was not changed in the presence of CN (6.88 +/- 0.18, n= 6). Since there was no difference in the intrinsic H+ buffering power, the estimation of the net acid efflux demonstrated that the activity of NHE-1 was significantly depressed in 2-DG. The inhibitory effect of 2-DG was not due to more extensive depletion of global intracellular ATP or secondary to the change in either intracellular Na+ or Ca2+ concentration. We concluded that ATP generated by glycolysis rather than by oxidative phosphorylation is essential to activate NHE-1 in ventricular myocytes.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 23/01/20 alle ore 04:21:47