ATP regulates sodium channel kinetics in pancreatic islet beta cells

Abstract

Pancreatic beta cells act as glucose sensors, in which intracellular ATP ([ATP](i)) are altered with glucose concentration change. The characterization of voltage-gated sodium channels under different [ATP](i) remains unclear. Here, we demonstrated that increasing [ATP](i) within a certain range of concentrations (2-8 mM) significantly enhanced the voltage-gated sodium channel currents, compared with 2 mM cytosolic ATP. This enhancement was attenuated by even high intracellular ATP (12 mM). Furthermore, elevated ATP modulated the sodium channel kinetics in a dose-dependent manner. Increased [ATP](i) shifted both the current-voltage curve and the voltage-dependent inactivation curve of sodium channel to the right. Finally, the sodium channel recovery from inactivation was significantly faster when the intracellular ATP level was increased, especially in 8 mM [ATP](i), which is an attainable concentration by the high glucose stimulation. In summary, our data suggested that elevated cytosolic ATP enhanced the activity of Na(+) channels, which may play essential roles in modulating cell excitability and insulin release when blood glucose concentration increases.

Keywords

Langerhansovi otočki;trebušna slinavka;

Data

Language:	English
Year of publishing:	2013
Typology:	1.01 - Original Scientific Article
Organization:	UM MF - Faculty of Medicine
UDC:	612.349.7
COBISS:	512288568
ISSN:	0022-2631
Views:	1463
Downloads:	191
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	Unknown
Secondary keywords:	Islets of Langerhans;Pancreas;physiology;
URN:	URN:SI:UM:
Type (COBISS):	Not categorized
Pages:	str. 101-107
Volume:	ǂVol. ǂ246
Issue:	ǂiss. ǂ2
Chronology:	2013
Keywords (UDC):	applied sciences;medicine;technology;uporabne znanosti;medicina;tehnika;medical sciences;medicina;physiology;human and comparative physiology;fiziologija;fiziologija človeka in primerjalna fiziologija;alimentation;eating;digestion;nutrition;prehranjevanje;hranjenje;prebava;nutracija;
DOI:	10.1007/s00232-012-9506-7
ID:	1439898