Regulation of sodium influx and sodium, potassium pump activity by a sodium-hydrogen antiport in rat vascular smooth muscle.
1. The effects of Na-H antiport inhibitors on sodium influx, intracellular pH and Na,K-pump activity were examined in vascular smooth muscle from rats. 2. Amiloride and 5-(N-ethyl-N-isopropyl)amiloride inhibited Na accumulation following inhibition of the Na,K-pump. 3. Inhibition of Na influx was associated with a reduction in basal Na,K-pump activity and intracellular pH. 4. It is concluded that a Na-H antiport system in vascular smooth muscle regulates Na influx rate, contributes to intracellular pH regulation and influences basal levels of Na,K-pump activity.
D000584:Amiloride / Q000494:pharmacology; D000818:Animals; D001011:Aorta; D002478:Cells, Cultured; D046508:Culture Techniques; D006863:Hydrogen-Ion Concentration; D007424:Intracellular Fluid / Q000378:metabolism; D007473:Ion Channels; D009131:Muscle, Smooth, Vascular / Q000378:metabolism*; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium; D051381:Rats; D011919:Rats, Inbred Strains; D012964:Sodium; D013050:Spectrometry, Fluorescence
D007473:Ion Channels; D010042:Ouabain; D000584:Amiloride; D012964:Sodium; D011188:Potassium