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Pflügers Archiv

, Volume 406, Issue 1, pp 69–72 | Cite as

Ensemble noise and current relaxation analysis of K+ current in single isolated salivary acinar cells from rat

  • Y. Maruyama
  • A. Nishiyama
  • T. Izumi
  • N. Hoshimiya
  • O. H. Petersen
Transport Processes, Metabolism and Endocrinology; Kidney, Gastrointestinal Tract, and Exocrine Glands

Abstract

The K+ channel in rat parotid gland acinar cells were investigated by ensemble current noise analysis in single isolated cells employing the giga-seal whole cell current recording mode. Sets of 20–40 identical de- and hyperpolarization voltage steps were applied and the resultant current records were processed by computer to obtain the mean and the variance of the current. The time-course of the mean current could be fitted by the sum of two exponentials, suggesting a 3-state model. The simplest plausible hypothesis is a model with one open and two closed states. Assuming this model, the relationship between the variance (σ2) and the mean current (I) could be fitted by the function σ2/I=i−I/N. The estimated single channeli/V-relations were similar to those taken from single channel current recordings, and the size of the population of channels per cell (N) was 76±26 (n=12). The validity of the model was tested by a successful simulation of the time-course of the variance.

Key words

K+ channels Acinar cells Ensemble noise analysis Current relaxation Patch-clamp whole cell recording 

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Copyright information

© Springer-Verlag 1986

Authors and Affiliations

  • Y. Maruyama
    • 1
  • A. Nishiyama
    • 1
  • T. Izumi
    • 2
  • N. Hoshimiya
    • 2
  • O. H. Petersen
    • 3
  1. 1.Department of PhysiologyTohoku University School of MedicineSendaiJapan
  2. 2.R.I.A.E. Hokkaido UniversitySapporoJapan
  3. 3.MRC Secretory Control Group, Physiological LaboratoryUniversity of LiverpoolLiverpoolUK

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