Reduced presynaptic dopamine receptor density after chronic antidepressant treatment in rats.
Chronic administration of desipramine and nomifensine to rats reduced the number of presynaptic dopamine receptors as labeled by 3H-dopamine in rat striatal tissues, with no change in receptor affinity. This change can only be brought about by continuous daily treatment with antidepressants for a duration of at least 21 days or longer. All antidepressants did not displace 3H-spiperone or 3H-dopamine at low concentrations in vitro, suggesting that the agents may not act on the dopamine receptors directly. A possible interaction between neurotransmitters in the central nervous system for the overall therapeutic effect of antidepressant drugs was proposed.
D000818:Animals; D003342:Corpus Striatum / Q000187:drug effects* / Q000378:metabolism; D003891:Desipramine / Q000494:pharmacology*; D004298:Dopamine / Q000378:metabolism*; D007546:Isoquinolines / Q000494:pharmacology*; D008297:Male; D009627:Nomifensine / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000187:drug effects* / Q000378:metabolism; D013134:Spiperone / Q000378:metabolism; D013569:Synapses / Q000187:drug effects* / Q000378:metabolism
D007546:Isoquinolines; D011954:Receptors, Dopamine; D009627:Nomifensine; D013134:Spiperone; D003891:Desipramine; D004298:Dopamine