Possible Interaction: Quinine and Serotonin

“For supra-threshold stimuli, acutely reduced serotonin levels significantly enhanced the perceived intensity of both bitter and sour tastes and blunted pleasantness ratings of bitter quinine.”

“As tryptophan is a precursor of the neurotransmitter serotonin (5-HT), here we test the hypothesis that quinine disrupts serotonin function.”

“Furthermore, cells exhibited marked decreases in serotonin production during incubation with quinine.”

“One possible cause of this effect is through inhibition of 5-HT receptor activation by quinine , as we observed here.”

“Measurement of taste function in healthy humans before and after a 5-HT reuptake inhibitor, NA reuptake inhibitor, or placebo showed that enhancing 5-HT significantly reduced the sucrose taste threshold by 27% and the quinine taste threshold by 53%.”

“5‐MT injection into the raphe nuclei of PCPA‐(tryptophan hydroxylase inhibitor)‐pretreated rats increased the tissue concentration of serotonin (from 40 to 90% of the control value, respectively, in the striatum), while the CYP2D inhibitor quinine diminished serotonin level in some brain structures of those animals (Model‐A).”

“Verapamil, apamin, …, quinine and charybdotoxin reduced the contractile responses induced by ACh and 5-HT in ileum from rabbits treated with SWCNTs, indicating that voltage-dependent Ca2+ channels and small, intermediate, and large-conductance Ca(2+)-activated, ATP-sensitive, and voltage-dependent K+ channels are involved in these effects.”

“When combined with QUIN , all drugs that act via inhibition of 5-HT uptake (imipramine, amitriptyline, citalopram, paroxetine, fluoxetine and fluvoxamine) significantly increased the swimming time of mice.”

“The consumption of water, quinine , citric acid or saline was increased by 5-HT , whereas the consumption of sucrose, saccharin or milk was decreased.”

“The continuous intranigral perfusion of the D2-receptor agonist, (-)-quinpirole HCl (1 microM) significantly decreased both DA ad 5-HT release to 71% and 78%, respectively.”

“On the basis of these findings, together with those in the preceding two papers, it is suggested that the effects of rubidium, caesium and quinine , to enhance differentially various aspects of 5-HT function are mediated by actions on 5-HT-modulated K(+)-channels.”

“ Quinine also enhanced the rate of synthesis of 5-HT in the brain of the rat.”

“A few cells were inhibited by 5-HT creatinine sulphate.”