Effect of Quinine Solutions on Intracellular Ca~(2+) Levels in Neuro-2a Cells-Conventional Physiological Method for the Evaluation of Bitterness-

摘要

The purpose of the present study was to examine the effect of quinine on intracellular Ca~(2+) ([Ca~(2+)]_i) levels in cultured neuro-2a cells, and to investigate the possibility of using [Ca~(2+)]_i levels to predict the bitterness of quinine solutions. [Ca~(2+)]_i levels in neuro-2a cells increased following stimulation by quinine in a concentration-related manner. There was a good linear correlationship between the quinine-induced increase in [Ca~(2+)]_i levels increase and the bitterness scores of the quinine solutions as assessed in human gustatory sensation tests (r~2 = 0.918). The quinine-induced increase in [Ca~(2+)]_i levels was inhibited by thapsigargin (an inhibitor of the Ca~(2+) pump into intracellular stores), U73122 (an inhibitor of phospholipase C) and ω-conotoxin (an N-type Ca~(2+)-channel blocker), but not by nifedipine (an L-type Ca~(2+)-channel blocker).