The effect of imiquimod on taste bud calcium transients and transmitter secretion

Abstract

Our results provide evidence that there is a subset of taste cells equipped with a range of intracellular mechanisms that respond to imiquimod. The findings are also consistent with a role of imiquimod as an immune response modifier, which shapes peripheral taste responses via 5-HT signalling.

Substance P as a putative efferent transmitter mediates GABAergic inhibition in mouse taste buds

“…Huang et al, ). The average baseline (resting) Ca 2+ of taste cells in these experiments was 160 ± 42 nM ( n = 39 cells), which corresponds well with values reported previously (Huang et al, ; Huang and Wu, ; ). Our criteria for accepting Ca 2+ responses for analysis are described fully in the previous publications (Huang et al, ; Huang and Wu, ).…”

“…We hypothesize that GABA evoked by SP mediates inhibitory interactions within the taste bud during gustatory stimulation. Previous studies showed that taste stimulation elicits ATP release from intact taste buds isolated from lingual epithelium (Huang et al, ; ; Murata et al, ; Dvoryanchikov et al, ; Huang and Wu, ; ). ATP is believed to be an important excitatory transmitter between taste buds and gustatory sensory afferent fibres (Finger et al, ; Huang et al, ; Vandenbeuch et al, ).…”

“…Dispersed taste buds and taste cells were isolated as described previously (Huang and Wu, ; ). Briefly, we injected an enzyme cocktail containing 1 mg·mL −1 collagenase A (Roche, Indianapolis, IN, USA), 2.5 mg·mL −1 dispase II (Roche), 2 mg·mL −1 elastase (Worthington, Lakewood, NJ, USA) and 1 mg·mL −1 trypsin inhibitor (Sigma, St. Louis, MO, USA) beneath the epithelium surrounding circumvallate papillae and removed the lingual epithelium.…”

“…Moreover, this procedure produced reliable and consistent stimulus‐evoked responses from isolated taste cells, as described in Huang et al . (, ) and Huang and Wu (, ). All experiments were conducted at room temperature.…”

“…Isolated taste buds were fixed in 4% paraformaldehyde in PBS for 10–20 min at 4°C and immunostained following the procedures as described in Huang and Wu (, ). is exclusively expressed in Type I cells in vallate taste buds (Lawton et al, ; Vandenbeuch et al, ; Yoshida et al, ).…”