Down-regulation of dopamine1 (D1) receptors by chronic imipramine is species-specific.
Chronic treatment with imipramine (15 mg/kg, twice daily for 14 days) induces a down-regulation of limbic D1 receptors in rats but not in mice. In this mouse strain, both chronic and acute imipramine treatment have been shown to produce clear behavioral effects in the forced swim test. While the data presented here are consistent with previously reported findings in rats, they demonstrate that the down-regulation of D1 receptors by chronic antidepressant treatment is species-specific. This phenomenon indicates that D1 receptor down-regulation is not critical to the therapeutic mechanism of action of antidepressants.
Nowak
G
G
Laboratory of Neuroscience, National Institute of Diabetes, Digestive, and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892.
Skolnick
P
P
Paul
I A
IA
D000818:Animals; D001552:Benzazepines / Q000494:pharmacology; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism; D015536:Down-Regulation / Q000187:drug effects*; D007099:Imipramine / Q000494:pharmacology*; D008032:Limbic System / Q000187:drug effects / Q000378:metabolism; D008297:Male; D051379:Mice; D011869:Radioligand Assay; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000187:drug effects*; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D013045:Species Specificity
D001552:Benzazepines; D011954:Receptors, Dopamine; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D007099:Imipramine