The effect of a glucocorticoid on olfactory response of isolated mouse olfactory cells

Oral administration and nasal instillation of glucocorticoids are currently being conducted and are producing satisfactory results for the treatment of olfactory dysfunctions. However, there are still many unanswered questions about the actions of glucocorticoids on the olfactory cells. In the present study, the effects of glucocorticoids on the olfactory response in mouse olfactory cells were examined by measuring changes in the intracellular Ca2+ concentration. The olfactory cells isolated from the BALB/c female mouse mucosa were stained with a Fura-2/AM and the changes in the intracellular Ca2+ concentration were observed by using a fluorescent microscopic image processing device, ARGUS50. The cells were exposed to the following olfactory stimuli, 3-ethoxy-4-hydroxy-benzaldehyde, caprylic acid, nonanoic acid, phenethyl alcohol and n-amyl acetate. When 0.1 and 0.01% betamethasone was applied to the olfactory cells for short periods(1 or 3 minutes), no changes were observed. However, long-term(7 minutes) application of 0.1 and 0.01% (but not 0.001 and 0.0001%) betametathone significantly decreased intracellular Ca2+ concentration, which was increased by olfactory stimulation. The inhibitory effect of betamethasone on Ca2+ influx into olfactory cells was attenuated by pre-treatment olfactory cells with RU486, a glucocorticoid receptor antagonist.