THE EXOCYTOTIC FUSION PORE OF SMALL GRANULES HAS A CONDUCTANCE SIMILAR TO AN ION-CHANNEL

被引:109
作者
LOLLIKE, K
BORREGAARD, N
LINDAU, M
机构
[1] MAX PLANCK INST MED RES,DEPT MOLEC CELL RES,D-69120 HEIDELBERG,GERMANY
[2] NATL UNIV HOSP,DEPT INTERNAL MED & HAEMATOL L,GRANULOCYTE RES LAB,DK-2100 COPENHAGEN,DENMARK
关键词
D O I
10.1083/jcb.129.1.99
中图分类号
Q2 [细胞生物学];
学科分类号
071009 ; 090102 ;
摘要
We measured capacitance changes in cell attached patches of human neutrophils using a high frequency lock-in method. With this technique the noise level is reduced to 0.025 fF such that capacitance steps of 0.1 fF are clearly detected corresponding to exo- and endocytosis of single 60 nm vesicles. It is thus possible to detect almost all known exocytotic and endocytotic processes including exocytosis of small neurotransmitter containing vesicles in most cell types as well as endocytosis of coated and uncoated pits. In neutrophils we demonstrate a stepwise capacitance decrease generated by 60-165 nm vesicles as expected for endocytosis of coated and non-coated pits. Following ionomycin stimulation a stepwise capacitance increase is observed consisting of 0.1-5 fF steps corresponding to the different granule types of human neutrophils from secretory vesicles to azurophil granules. The opening of individual fusion pores is resolved during exocytosis of 200 nm vesicles. The initial conductance has a mean value of 150 pS and can be as low as 35 pS which is similar to the conductance of many ion channels suggesting that the initial fusion pore is formed by a protein complex.
引用
收藏
页码:99 / 104
页数:6
相关论文
共 34 条
  • [1] TRANSMITTER RELEASE FROM SYNAPSES - DOES A PREASSEMBLED FUSION PORE INITIATE EXOCYTOSIS
    ALMERS, W
    TSE, FW
    [J]. NEURON, 1990, 4 (06) : 813 - 818
  • [2] EXOCYTOSIS
    ALMERS, W
    [J]. ANNUAL REVIEW OF PHYSIOLOGY, 1990, 52 : 607 - 624
  • [3] 2 ROLES FOR GUANINE-NUCLEOTIDES IN THE STIMULUS-SECRETION SEQUENCE OF NEUTROPHILS
    BARROWMAN, MM
    COCKCROFT, S
    GOMPERTS, BD
    [J]. NATURE, 1986, 319 (6053) : 504 - 507
  • [4] CHEMOATTRACTANT-REGULATED MOBILIZATION OF A NOVEL INTRACELLULAR COMPARTMENT IN HUMAN-NEUTROPHILS
    BORREGAARD, N
    MILLER, LJ
    SPRINGER, TA
    [J]. SCIENCE, 1987, 237 (4819) : 1204 - 1206
  • [5] BORREGAARD N, 1993, EUR J HAEMATOL, V51, P187
  • [6] BOYUM A, 1968, SCAND J CLIN LAB INV, VS 21, P77
  • [7] CURRENTS THROUGH THE FUSION PORE THAT FORMS DURING EXOCYTOSIS OF A SECRETORY VESICLE
    BRECKENRIDGE, LJ
    ALMERS, W
    [J]. NATURE, 1987, 328 (6133) : 814 - 817
  • [8] CALAFAT J, 1993, BLOOD, V81, P3122
  • [9] CURRAN MJ, 1993, J MEMBRANE BIOL, V133, P61
  • [10] A PATCH-CLAMP STUDY OF BOVINE CHROMAFFIN CELLS AND OF THEIR SENSITIVITY TO ACETYLCHOLINE
    FENWICK, EM
    MARTY, A
    NEHER, E
    [J]. JOURNAL OF PHYSIOLOGY-LONDON, 1982, 331 (OCT): : 577 - 597