Biochemical and Biophysical Research Communications, Vol.355, No.4, 1019-1024, 2007
Involvement of the calcium channel beta 3 subunit in olfactory signal transduction
Despite the expression of voltage-dependent Ca2+ channels in nasal turbinate epithelium, their role in odorant chemosensation has remained obscure. Therefore, we investigated olfactory neurotransduction in beta 3-deficient mice. RT-PCR and Western blots confirmed the expression of various types of Ca2+ channels in the nasal turbinate. Electrophysiological evaluations revealed that beta 3-null mice had a 60% reduction in the high-voltage-dependent Ca2+ currents in olfactory receptor neurons due to reduced N- and L-type channel currents. The beta 3-null mice showed increased olfactory neuronal activity to triethylamine, and this effect was mimicked by the perfusion of the specific N-type Ca2+ channel inhibitor omega-conotoxin GVIA in the electro-olfactogram. Diluted male urine odors induced higher Fos immunoreactivity in the main olfactory bulbs of beta 3-deficient mice, indicating enhanced signal transduction of odor information in these mice. Our data indicate the involvement of voltage-dependent Ca2+ channels and importance of the beta 3 subunit in olfactory signal transduction. (c) 2007 Elsevier Inc. All rights reserved.