Stimulatory action of endothelin-1 on membrane Na+ transport in vascular smooth muscle cells in culture.
Endothelin-1 was able to induce an immediate and transient increase in cytosolic free Ca2+ concentrations in the A10 cell line of vascular smooth muscle. This was associated with a strong stimulation of the Na+:H+ exchange, the Na+, K+ pump and the [Na+,K+,Cl-]-cotransport system. Pump stimulation appeared to be secondary to sodium entry through Na+:H+ exchange because it was absent in Na+ loaded cells and in the presence of ethyl-isopropyl-amiloride. Cotransport stimulation was blocked by indomethacin, suggesting the involvement of a cyclooxygenase product. In conclusion, the monovalent ionic perturbations associated to the vasoconstrictor and mitogenic actions of endothelin-1 are counterbalanced by activation of the Na+,K+ pump and the [Na+,K+,Cl-]-cotransport system.
Rosati
C
C
INSERUM U7/CNRS UA 318, Hôpital Necker, Paris, France.
Jeanclos
E
E
Cavalier
S
S
Chabrier
P E
PE
Hannaert
P
P
Braquet
P
P
Garay
R
R
D000818:Animals; D001692:Biological Transport / Q000187:drug effects / Q000502:physiology; D002118:Calcium / Q000032:analysis; D002352:Carrier Proteins / Q000502:physiology; D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects / Q000502:physiology; D002463:Cell Membrane Permeability / Q000187:drug effects* / Q000502:physiology; D002478:Cells, Cultured; D003600:Cytosol / Q000737:chemistry; D016232:Endothelins / Q000494:pharmacology*; D006801:Humans; D009131:Muscle, Smooth, Vascular / Q000166:cytology* / Q000502:physiology / Q000648:ultrastructure; D012964:Sodium / Q000493:pharmacokinetics*; D017923:Sodium-Hydrogen Exchangers; D028021:Sodium-Potassium-Chloride Symporters
D002352:Carrier Proteins; D016232:Endothelins; D017923:Sodium-Hydrogen Exchangers; D028021:Sodium-Potassium-Chloride Symporters; D012964:Sodium; D002118:Calcium