ATP-SENSITIVE K+-CHANNEL RUN-DOWN IS MG2+ DEPENDENT

被引:76
作者
KOZLOWSKI, RZ [1 ]
ASHFORD, MLJ [1 ]
机构
[1] UNIV CAMBRIDGE, DEPT PHARMACOL, CAMBRIDGE CB2 1QJ, ENGLAND
来源
PROCEEDINGS OF THE ROYAL SOCIETY SERIES B-BIOLOGICAL SCIENCES | 1990年 / 240卷 / 1298期
关键词
D O I
10.1098/rspb.1990.0044
中图分类号
Q [生物科学];
学科分类号
07 ; 0710 ; 09 ;
摘要
ATP- sensitive K+-channel currents were recorded from isolated membrane patches and voltage-clamped CRI-G1 insulin-secreting cells. Internal Mg2+ ions inhibited ATP-K+ channels by a voltage-dependent block of the channel current and decrease of open-state probability. The rundown of ATP-K+ channel activity was also shown to be [Mg2+](i) dependent, being almost abolished in Mg2+-free conditions. Substitution of Mn2+ for Mg2+ did not prevent run-down, nor did the presence of phosphate-donating nucleotides, a protease or phosphatase inhibitor or replacement of Cl- by gluconate.
引用
收藏
页码:397 / 410
页数:14
相关论文
共 38 条
  • [1] VOLTAGE-ACTIVATED CALCIUM CHANNELS THAT MUST BE PHOSPHORYLATED TO RESPOND TO MEMBRANE DEPOLARIZATION
    ARMSTRONG, D
    ECKERT, R
    [J]. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1987, 84 (08) : 2518 - 2522
  • [2] ASHCROFT FM, 1987, J PHYSIOL-LONDON, V390, pP72
  • [3] EFFECTS OF 2-KETOISOCAPROATE ON INSULIN RELEASE AND SINGLE POTASSIUM CHANNEL ACTIVITY IN DISPERSED RAT PANCREATIC BETA-CELLS
    ASHCROFT, FM
    ASHCROFT, SJH
    HARRISON, DE
    [J]. JOURNAL OF PHYSIOLOGY-LONDON, 1987, 385 : 517 - 529
  • [4] ASHCROFT FM, 1988, ANNU REV NEUROSCI, V11, P97, DOI 10.1146/annurev.ne.11.030188.000525
  • [5] ADENOSINE-5'-TRIPHOSPHATE-SENSITIVE ION CHANNELS IN NEONATAL RAT CULTURED CENTRAL NEURONS
    ASHFORD, MLJ
    STURGESS, NC
    TROUT, NJ
    GARDNER, NJ
    HALES, CN
    [J]. PFLUGERS ARCHIV-EUROPEAN JOURNAL OF PHYSIOLOGY, 1988, 412 (03): : 297 - 304
  • [6] RUN-DOWN OF THE CA CURRENT DURING LONG WHOLE-CELL RECORDINGS IN GUINEA-PIG HEART-CELLS - ROLE OF PHOSPHORYLATION AND INTRACELLULAR CALCIUM
    BELLES, B
    MALECOT, CO
    HESCHELER, J
    TRAUTWEIN, W
    [J]. PFLUGERS ARCHIV-EUROPEAN JOURNAL OF PHYSIOLOGY, 1988, 411 (04): : 353 - 360
  • [7] CALCIUM CURRENTS IN INTERNALLY PERFUSED NERVE-CELL BODIES OF LIMNEA-STAGNALIS
    BYERLY, L
    HAGIWARA, S
    [J]. JOURNAL OF PHYSIOLOGY-LONDON, 1982, 322 (JAN): : 503 - 528
  • [8] CARRINGTON CA, 1988, J ENDOCRINOL, V109, P193
  • [9] AN ENZYMATIC MECHANISM FOR CALCIUM CURRENT INACTIVATION IN DIALYZED HELIX NEURONS
    CHAD, JE
    ECKERT, R
    [J]. JOURNAL OF PHYSIOLOGY-LONDON, 1986, 378 : 31 - 51
  • [10] Dempster J, 1988, MICROCOMPUTERS PHYSL, P51