Effect of a specific 5HT uptake inhibitor (citalopram) on drug accumulation by rat lung slices.

Rat lung slices were used to examine the effects of citalopram, a compound reported to be a specific inhibitor of neuronal uptake of 5-hydroxytryptamine (5HT), on the pulmonary accumulation of 5HT, noradrenaline (NA), imipramine (IP) and paraquat (PQ). 5 X 10(-9) mol/l citalopram inhibited 5HT uptake by 30-40% but NA uptake was not affected at any of the concentrations of citalopram studied. At the highest concentrations of citalopram (10(-5) to 10(-4) mol/l) the accumulation of IP and PQ was reduced by25-30%. It is concluded that at low concentrations, citalopram is a specific and potent inhibitor of 5HT uptake by rat lung slices.