Effect of quinine solutions on intracellular Ca2+ levels in neuro-2a cells--conventional physiological method for the evaluation of bitterness.
The purpose of the present study was to examine the effect of quinine on intracellular Ca2+ ([Ca2+]i) levels in cultured neuro-2a cells, and to investigate the possibility of using [Ca2+]i levels to predict the bitterness of quinine solutions. [Ca2+]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 [Ca2+]i levels increase and the bitterness scores of the quinine solutions as assessed in human gustatory sensation tests (r2=0.918). The quinine-induced increase in [Ca2+]i levels was inhibited by thapsigargin (an inhibitor of the Ca2+ pump into intracellular stores), U73122 (an inhibitor of phospholipase C) and omega-conotoxin (an N-type Ca2+-channel blocker), but not by nifedipine (an L-type Ca2+-channel blocker).
Nakamura
Tomoko
T
School of Pharmaceutical Sciences, Mukogawa Women's University, Nishinomiya, Hyogo, Japan.
Akiyoshi
Takeshi
T
Tanaka
Naoko
N
Shinozuka
Kazumasa
K
Matzno
Sumio
S
Nakabayashi
Toshikatsu
T
Matsuyama
Kenji
K
Kashiwayanagi
Makoto
M
Uchida
Takahiro
T
D000328:Adult; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D004341:Drug Evaluation / Q000379:methods; D005260:Female; D006801:Humans; D007424:Intracellular Fluid / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D051379:Mice; D019999:Pharmaceutical Solutions / Q000494:pharmacology; D011803:Quinine / Q000494:pharmacology*; D013649:Taste / Q000187:drug effects* / Q000502:physiology
D019999:Pharmaceutical Solutions; D011803:Quinine; D002118:Calcium