title: Inhibition of vascular smooth muscle cell migration by elevation of extracellular potassium concentration.
abstract: The effect of potassium on the migration of vascular smooth muscle cells was analyzed in media made with extracellular potassium concentrations of 3, 4, 5, and 6 mmol/L. The migration of cultured porcine coronary artery cells was stimulated with platelet-derived growth factor (PDGF)-BB. In the first study, cells were exposed to PDGF-BB at concentrations of 0, 10, or 20 ng/mL for 5 hours with the use of a Boyden chamber. Cells were quiescent overnight in 0.5% fetal bovine serum in Dulbecco's modified Eagle's medium with an extracellular potassium concentration of 4 mmol/L. With increasing potassium concentration, migration was significantly inhibited (P<0. 02, 2-way ANOVA). In the cells exposed to 10 ng/mL PDGF-BB, migration ranged from 500+/-86% to 294+/-44% (value in wells with 0 ng/mL PDGF-BB and 4 mmol/L potassium concentration=100%) in medium containing 3 to 6 mmol/L extracellular potassium concentration (P<0. 03). Long-term potassium exposure was investigated in cells grown in 5% serum in Dulbecco's modified Eagle's medium with an extracellular potassium concentration of 3, 4, 5, or 6 mmol/L for 3 to 4 weeks. Migration was assessed with 0 or 20 ng/mL PDGF-BB. Migration was significantly inhibited by the elevation of extracellular potassium concentration (P<0.01, 2-way ANOVA). With 20 ng/mL PDGF-BB, the migration rates ranged from 152+/-11% in medium with 3 mmol/L potassium to 69+/-5% in 6 mmol/L potassium (P<0.01). Increases in extracellular potassium concentration within the physiological range significantly and directly inhibit vascular smooth muscle cell migration.
authors.affiliation: Department of Physiology and Biophysics , University of Mississippi Medical Center, Jackson, MS 39216-4505, USA.
authors.forename: G
authors.initials: G
authors.lastname: Ma
authors.forename: D P
authors.initials: DP
authors.lastname: Mason
authors.forename: D B
authors.initials: DB
authors.lastname: Young
mesh_terms: D000818:Animals; D000077214:Becaplermin; D002417:Cattle; D002455:Cell Division; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D009131:Muscle, Smooth, Vascular / Q000378:metabolism* / Q000473:pathology*; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism* / Q000494:pharmacology; D020574:Proto-Oncogene Proteins c-sis; D013552:Swine; D013997:Time Factors
chemical_list: D010982:Platelet-Derived Growth Factor; D020574:Proto-Oncogene Proteins c-sis; D000077214:Becaplermin; D011188:Potassium