The contribution of a Ca(2+)-activated Cl(-) conductance to amino-acid-induced inward current responses of ciliated olfactory neurons of the rainbow trout.
The contribution of a Ca(2+)-activated Cl(-) conductance to amino-acid-induced inward current responses of ciliated olfactory neurons of the rainbow trout.
复制标题
Ca(2)激活的Cl(-)电导对氨基酸诱导的虹鳟纤毛嗅神经元内向电流反应的贡献。
DOI:
10.1242/jeb.203.2.253
复制
发表时间:
2000
期刊:
影响因子:
--
通讯作者:
N. Suzuki
中科院分区:
文献类型:
--
作者:
K. Sato;N. Suzuki
To determine whether amino-acid-induced inward currents of ciliated olfactory receptor neurons (ORNs) in rainbow trout (Oncorhynchus mykiss) include a Ca(2+)-activated Cl(-) conductance, we first studied changes in reversal potential and the current/voltage relationships of the responses of ORNs to an amino acid mixture (l-alanine, l-arginine, l-glutamate and l-norvaline; all 10 mmol l(-)(1)) with different concentrations of Na(+) and Cl(-) in the perfusion and recording pipette solutions. We also examined the effects of six different Cl(-) channel blockers on the responses of ORNs using a conventional whole-cell voltage-clamp technique. The amino acid mixture and one blocker were applied focally to the cilia of ORNs using a double-barrelled micropipette and a pressure ejection system. The expected shifts in reversal potential, indicating the contribution of the Ca(2+)-activated Cl(-) conductance, occurred in both positive and negative directions depending on the external and internal Na(+) and Cl(-) concentrations. Niflumic acid, flufenamic acid, NPPB [5-nitro-2-(3-phenylpropylamino)-benzonate] and DCDPC (3', 5-dichlorodiphenylamine-2-carboxylate), at 0.5 mmol l(-)(1), reversibly blocked both the amino-acid-induced inward currents and the background activity in most ORNs. The effectiveness of these blocking agents varied from 77 to 91 % for ORNs perfused externally with standard Ringer's solution. SITS (4-acetamido-4'-isothiocyanatostilbene-2,2'-disulphonate), at 5.0 mmol l(-)(1), irreversibly inhibited the physiological response (100 % inhibition), whereas DIDS (4,4'-diisothiocyanatostilbene-2, 2'-disulphonate), at 5.0 mmol l(-)(1), had the smallest effect (45 %) of the inhibitors tested. The dose of niflumic acid inducing 50 % inhibition (IC(50)), determined specifically for the current component of the Ca(2+)-activated Cl(-) channels, was 70 micromol l(-)(1). Our results suggest that these blockers are not specific for Ca(2+)-activated Cl(-) channels and that the density of these channels varies between individual ORNs. Our results also show that the Ca(2+)-activated Cl(-) conductance plays an important role in olfactory transduction and allows fishes to adapt to various ionic environments.
登录
查看更多内容
DOI:
10.1242/jeb.195.1.307
发表时间:
1994
期刊:
The Journal of experimental biology
影响因子:
--
作者:
Kleene,SJ;Gesteland,RC;Bryant,SH
通讯作者:
Bryant,SH
DOI:
10.1152/jn.1995.74.1.479
发表时间:
1995
期刊:
Journal of neurophysiology.
影响因子:
--
作者:
Zhainazarov,AB;Ache,BW
通讯作者:
Ache,BW
影响因子:
56.9
作者:
RESTREPO, D;MIYAMOTO, T;TEETER, JH
通讯作者:
TEETER, JH
影响因子:
2.5
作者:
Okada,Y;Teeter,JH;Restrepo,D
通讯作者:
Restrepo,D
DOI:
10.1242/jeb.199.5.1115
发表时间:
1996
期刊:
The Journal of experimental biology
影响因子:
--
作者:
Corotto,FS;Piper,DR;Chen,N;Michel,WC
通讯作者:
Michel,WC