Artefactual inhibition of dopamine uptake by psychotropic drugs on striatal synaptosomal preparation.
On striatal synaptosomal preparations, using a double labelling test, numerous antidepressant drugs demonstrated an inhibitory effect on [3H]DA uptake at the same high concentrations producing a [14C]DA release. This releasing effect was also shared by non-antidepressant agents and was observed on synaptosomes preloaded with [3H]5HT. The imipramine-induced release of DA was not modified by increasing concentration of K+, by decreasing concentration of Na+, by deleting Ca2+ from the incubation medium, or by blocking the catecholamine uptake systems with nomifensine or cocaine. The imipramine effect was reversible and was possibly initiated by a transient physico-chemical modification of the synaptosomal membrane. It was concluded that the DA uptake carrier is probably not involved in the effect of these drugs.
D000818:Animals; D000928:Antidepressive Agents / Q000494:pharmacology; D002997:Clomipramine / Q000494:pharmacology; D003342:Corpus Striatum / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism*; D007099:Imipramine / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D011619:Psychotropic Drugs / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism; D013574:Synaptosomes / Q000378:metabolism*
D000928:Antidepressive Agents; D011619:Psychotropic Drugs; D012701:Serotonin; D002997:Clomipramine; D007099:Imipramine; D004298:Dopamine