and release of dopamine as well as firing rates of dopaminergic neurons are controlled by stimulation of autoreceptors via a negative feedback regulation. Investigations on therapeutic effects of autoreceptor-nonselective dopamine agonists in schizophrenia have yielded inconsistent results. Dopamine autoreceptor agonists like pramipexole, roxindole, talipexole and OPC-4392 as well as partial agonists like . Consequently, a nonselective dopamine agonistic action could be effective in some negative symptoms. Current evidence from several open and one placebo-controlled clinical trial suggests that some dopamine autoreceptor agonists like pramipexole, roxindole and talipexole may produce a mild improvement of symptoms like affective flattening, depressed mood, alogia and avolition. Nevertheless, these findings do
Endocrine characterization of the new dopamine autoreceptor agonist roxindole. Roxindole (5-Hydroxy-3-(4-phenyl-1,2,3,6-tetrahydropyridil-(1)-butyl)-indol) is a newly developed compound with a high dopamine autoreceptor agonistic potency at D2 receptors. Evaluation of roxindole for clinical purposes in psychiatric patients revealed that the substance has contrary to expectation merely negligible antipsychotic but considerable antidepressive effects. Interestingly it is nearly devoid of any side effects. To further characterize the endocrine effects, 1 mg roxindole was applied at 09:00 to 6 male volunteers and the effects compared to placebo. From 08:00 to 13:00 blood samples were drawn every 30 min. No effect on adrenocorticotropin and cortisol secretion was observed, neither mean plasma
Roxindole, a dopamine autoreceptor agonist, in the treatment of major depression. Roxindole is a potent autoreceptor-"selective" dopamine agonist originally developed for the treatment of schizophrenic syndromes. The drug also inhibits 5-HT uptake and has 5-HT1A agonistic actions. In this open clinical trial 12 in-patients suffering from a major depressive episode (DSM-III-R) were treated with roxindole for 28 days in a fixed dosage of 15 mg per day. A reduction of at least 50% in HAMD-17 total scores was observed in 8 out of 12 patients after 4 weeks (mean HAMD-17 reduction of 56% in all patients), while 4 patients did not respond to roxindole treatment. Half of the patients showed a complete psychopathological remission (HAMD-17 < 8). Roxindole's onset of antidepressant action was remarkably