Open AccessSystemic Modulation of Serotonergic Synapses via Reuptake Blockade or 5HT1A Receptor Antagonism Does Not Alter Perithreshold Taste Sensitivity in Rats
Author(s) -
Clare M. Mathes,
Alan C. Spector
Publication year - 2014
Publication title -
chemical senses
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.856
H-Index - 100
eISSN - 1464-3553
pISSN - 0379-864X
DOI - 10.1093/chemse/bju028
Subject(s) - serotonin , serotonergic , taste , paroxetine , endocrinology , medicine , agonist , psychology , reuptake inhibitor , pharmacology , autoreceptor , chemistry , receptor , neuroscience
Systemic blockade of serotonin (5HT) reuptake with paroxetine has been shown to increase sensitivity to sucrose and quinine in humans. Here, using a 2-response operant taste detection task, we measured the effect of paroxetine and the 5HT1A receptor antagonist WAY100635 on the ability of rats to discriminate sucrose, NaCl, and citric acid from water. After establishing individual psychometric functions, 5 concentrations of each taste stimulus were chosen to represent the dynamic portion of the concentration-response curve, and the performance of the rats to these stimuli was assessed after vehicle, paroxetine (7mg/kg intraperitoneally), and WAY100635 (0.3mg/kg subcutaneously; 1mg/kg intravenously) administration. Although, at times, overall performance across concentrations dropped, at most, 5% from vehicle to drug conditions, no differences relative to vehicle were seen on the parameters of the psychometric function (asymptote, slope, or EC50) after drug administration. In contrast to findings in humans, our results suggest that modulation of 5HT activity has little impact on sucrose detectability at perithreshold concentrations in rats, at least at the doses used in this task. In the rat model, the purported paracrine/neurocrine action of serotonin in the taste bud may work in a manner that does not impact overt taste detection behavior.