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Updated: Jun 9, 2026

Use of Label-free Optical Biosensors to Detect Modulation of Potassium Channels by G-protein Coupled Receptors
Published on: February 10, 2014
Modulation of potassium channels via the α1B-adrenergic receptor in human osteoblasts
Daisuke Kodama1, Akifumi Togari
1Department of Pharmacology, School of Dentistry, Aichi-Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya 464-8650, Japan.
Abstract:
Recent studies have demonstrated the involvement of the sympathetic nerve system in bone metabolism. We have previously demonstrated the expression of adrenergic receptors in the human osteoblast SaM-1 cell line. The aim of this study was to reveal the function of these receptors in osteoblasts using electrophysiological methods. During whole-cell patch clamp recording, the application of noradrenaline reduced the currents induced by a voltage ramp, and the effect was larger in the positive potential range. Pretreatment with the selective α(1B)-adrenergic receptor antagonist chloroethylclonidine eliminated the inhibitory effect of noradrenaline. Using Cs-based pipette solution to block potassium channels, the inhibitory effect of noradrenaline disappeared. In contrast, the effect was unaffected in the presence of tetraethylammonium (TEA), a potassium channel blocker. These results suggest that noradrenaline suppresses Cs-sensitive and TEA-insensitive potassium channels via the α(1B)-adrenergic receptor in human osteoblasts.
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