Calcium mediates the activation of the inhibitory current induced by odorants in toad olfactory receptor neurons

FEBS Letters

Bacigalupo, Juan¹  Madrid, Rodolfo¹  Morales, Bernardo¹ 

[1] Departamento de Biologı́a, Facultad de Ciencias, Universidad de Chile, P.O. Box 653, Santiago, Chile

关键词: Calcium;    Ca2+-activated K+ conductance;    Inhibition;    Nifedipine;    Olfactory neurons;   

DOI  :  10.1016/S0014-5793(97)00005-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

In toad olfactory neurons, a putrid odorant mixture inducing inhibitory responses increases Ca²⁺-activated K⁺ conductance, developing a hyperpolarizing receptor potential. Removal of extracellular Ca²⁺ or exposure to nifedipine reversibly reduced the inhibitory response, suggesting that odorants induce a Ca²⁺ influx. We show evidence for an odorant-induced Ca²⁺ current. Using confocal microscopy, it is shown that odorants induce a nifedipine-sensitive elevation of Ca²⁺ in the apical end of the cell. These results suggest an inhibitory mechanism in which an apical Ca²⁺ influx causes an increase in internal Ca²⁺, opening Ca²⁺-activated K⁺ channels that lead to membrane hyperpolarization. © 1997 Federation of European Biochemical Societies. All rights reserved.

【 授权许可】

Unknown