ISSN:
1432-1424
Keywords:
Anion channel
;
Chloride channel
;
Growth cone
;
DIDS
;
SITS
;
DNDS
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
Notes:
Abstract Chloride channels were reconstituted into planar lipid bilayers isolated from a preparation of growth cone particles (GCPs) isolated from fetal rat brain. One type of channel was predominantly seen and some of its biophysical and pharmacological properties were studied. The single channel i-V relationship was curvilinear with a chord conductance of 75 pS at +30 mV in symmetric 200 mm NaCl solutions buffered with phosphate. The channel was inactivated by depolarization, and this inactivation was reversed rapidly upon returning to −25 mV. The Cl− channel was significantly permeant to Na+ ions (P Na/P Cl=0.26), and the relative halide permeabilities were determined to be: I(1.92)〉Br(1.73)〉Cl(1.0)〉F(0.34). The channel was inhibited by the common stilbene compounds (DIDS, SITS, DNDS), as well as by Zn2+ ions and an indanyloxyacetic acid derivative. A developmental role for the GCP Cl− channel is suggested by the observation that adult rat brain synaptosomal membranes were nearly devoid of this type of Cl− channel. The authors thank Dr. Donald Landry, Columbia University, for the generous gift of 94-IAA, and Prof. Dale Benos, University of Albama, for helpful suggestions on chloride channel pharmacology made during the experiments. Drs. Stephen Raymond and G.K. Wang of the Anesthesia Research Laboratories of The Brigham and Women's Hospital are acknowledged for providing us with an amplifier and laser printer necessary for the construction of many of the figures. Ms. Ellen Jacobsen helped with the manuscript typing.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00232869
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