Intracellular electrolytes regulate the volume set point of the organic osmolyte/anion channel VSOAC

被引:52
作者
Emma, F
McManus, M
Strange, K
机构
[1] HARVARD UNIV, CHILDRENS HOSP,SCH MED,CRIT CARE RES LABS, DEPT ANESTHESIA, BOSTON, MA 02115 USA
[2] HARVARD UNIV, CHILDRENS HOSP,SCH MED,CRIT CARE RES LABS,DEPT MED, BOSTON, MA 02115 USA
[3] HARVARD UNIV, CHILDRENS HOSP, SCH MED, DIV NEPHROL, BOSTON, MA 02115 USA
来源
AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY | 1997年 / 272卷 / 06期
关键词
chloride channels; volume regulation; cell swelling; patch clamp;
D O I
10.1152/ajpcell.1997.272.6.C1766
中图分类号
Q2 [细胞生物学];
学科分类号
071009 ; 090102 ;
摘要
Regulation of the volume sensitivity of the swelling-activated organic osmolyte/anion channel VSOAC by intracellular electrolytes was examined in intact and patch-clamped C6 glioma cells. In intact cells, VSOAC activation was monitored by [H-3]taurine efflux measurements, and intracellular electrolyte concentrations were manipulated by acclimation to hypertonic medium for varying periods of time. Hypertonic shrinkage was followed by a rapid and complete regulatory volume increase mediated by electrolyte accumulation that elevated intracellular Na+, K+, and Cl- concentrations. During prolonged (4-48 h) exposure to hypertonicity, electrolyte concentrations decreased gradually as cells accumulated the organic osmolyte myo-inositol. VSOAC activation induced by cell swelling of 35-40% increased as a function of the time of exposure to hypertonicity and was inversely correlated with measured intracellular Na+, K+ and Cl- levels. In patch-clamped cells, swelling-induced Cl- current activation was unaffected by acclimation conditions but was inhibited by increasing the concentration of electrolytes in the patch pipette solution. Quantification of the relationship between VSOAC activation and cell swelling demonstrated that increases in intracellular electrolyte levels increase VSOAC volume set point. Regulation of VSOAC volume sensitivity by electrolytes allows cells to selectively utilize electrolytes or a combination of electrolytes and organic osmolytes for regulatory volume decrease (RVD). Control over the type of solute used for volume regulation is advantageous, allowing cells to control intracellular ionic composition and prevent increases in cytoplasmic ionic strength during RVD.
引用
收藏
页码:C1766 / C1775
页数:10
相关论文
共 20 条
  • [11] OSMOREGULATION OF NA+-INOSITOL COTRANSPORTER ACTIVITY AND MESSENGER-RNA LEVELS IN BRAIN GLIAL-CELLS
    PAREDES, A
    MCMANUS, M
    KWON, HM
    STRANGE, K
    [J]. AMERICAN JOURNAL OF PHYSIOLOGY, 1992, 263 (06): : C1282 - C1288
  • [12] EFFECTS OF IONIC-STRENGTH ON THE REGULATION OF NA/H EXCHANGE AND K-CL COTRANSPORT IN DOG RED-BLOOD-CELLS
    PARKER, JC
    DUNHAM, PB
    MINTON, AP
    [J]. JOURNAL OF GENERAL PHYSIOLOGY, 1995, 105 (06) : 677 - 699
  • [13] STRANGE K, 1994, NEWS PHYSIOL SCI, V9, P223
  • [14] METHODS FOR IMAGING RENAL TUBULE CELLS
    STRANGE, K
    SPRING, KR
    [J]. KIDNEY INTERNATIONAL, 1986, 30 (02) : 192 - 200
  • [15] Cellular and molecular physiology of volume-sensitive anion channels
    Strange, K
    Emma, F
    Jackson, PS
    [J]. AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY, 1996, 270 (03): : C711 - C730
  • [16] SWELLING-ACTIVATED ORGANIC OSMOLYTE EFFLUX - A NEW ROLE FOR ANION CHANNELS
    STRANGE, K
    JACKSON, PS
    [J]. KIDNEY INTERNATIONAL, 1995, 48 (04) : 994 - 1003
  • [17] UP-REGULATION OF INOSITOL TRANSPORT MEDIATES INOSITOL ACCUMULATION IN HYPEROSMOLAR BRAIN-CELLS
    STRANGE, K
    MORRISON, R
    HEILIG, CW
    DIPIETRO, S
    GULLANS, SR
    [J]. AMERICAN JOURNAL OF PHYSIOLOGY, 1991, 260 (04): : C784 - C790
  • [18] VOLUME REGULATION DURING RECOVERY FROM CHRONIC HYPERTONICITY IN BRAIN GLIAL-CELLS
    STRANGE, K
    MORRISON, R
    [J]. AMERICAN JOURNAL OF PHYSIOLOGY, 1992, 263 (02): : C412 - C419
  • [19] WEISSBACH A, 1974, METHOD ENZYMAT AN, P1333
  • [20] Yancey P, 1994, CELLULAR MOL PHYSL C, P81, DOI [10.1201/9780367812140-7, DOI 10.1201/9780367812140-7]