Hypoxia activates a background conductance in freshly isolated pulmonary arterial endothelial cells of the rat.
Utilising the patch-clamp recording technique we have demonstrated for the first time the effects of hypoxia on the background current in pulmonary arterial endothelial cells. Electrophysiological studies revealed the presence of a novel oxygen-sensitive, non-selective cation conductance (I(NSC)) in these cells. The inward component of I(NSC) was significantly potentiated by hypoxia. Both the inward and outward components of I(NSC) were inhibited by both La(3+) and Gd(3+). Hypoxic activation of I(NSC) may provide an important Ca(2+) influx pathway essential for the release of a pulmonary-selective vasoconstrictor pivotal to the sustained phase of hypoxic pulmonary vasoconstriction.
Hogg
Dayle S
DS
Department of Pharmacology, School of Medical Sciences, University of Bristol, University Walk, UK.
Kozlowski
Roland Z
RZ
D000584:Amiloride / Q000031:analogs & derivatives / Q000494:pharmacology; D000818:Animals; D015687:Cell Hypoxia; D002478:Cells, Cultured; D004594:Electrophysiology; D004730:Endothelium, Vascular / Q000166:cytology; D005682:Gadolinium / Q000494:pharmacology; D007811:Lanthanum / Q000494:pharmacology; D008297:Male; D010100:Oxygen / Q000378:metabolism*; D015221:Potassium Channels / Q000187:drug effects / Q000502:physiology*; D011651:Pulmonary Artery / Q000166:cytology; D051381:Rats; D017208:Rats, Wistar; D019831:Sodium-Calcium Exchanger / Q000037:antagonists & inhibitors
D015221:Potassium Channels; D019831:Sodium-Calcium Exchanger; D007811:Lanthanum; D000584:Amiloride; C064515:2',4'-dichlorobenzamil amiloride; D005682:Gadolinium; D010100:Oxygen