Haloperidol-desipramine interaction in mice, rats and man

Different effects of serotonin (5-HT) uptake blockers in caudate nucleus and hippocampus of the rabbit: role of monoamine oxidase in dopaminergic terminals

Slices of rabbit hippocampus or caudate nucleus were incubated with [3H]-5-HT (0.1 microM, 60 min) or with [3H]-DA. In hippocampal tissue, the 5-HT uptake blockers chlorimipramine, fluvoxamine, and 6-nitroquipazine (0.1, 1, 10 microM) reduced the percentage content of [3H]-5-HT in a concentration dependent manner. The degree of inhibition of [3H]-5-HT content produced by the 5-HT uptake inhibitors was not affected by the MAO inhibitors pargyline or amezinium (which by themselves enhanced [3H] loading) or the catecholamine uptake inhibitor nomifensine (which by itself did not affect [3H] loading). In caudate nucleus tissue, however, the [3H]-5-HT accumulation was reduced only at the highest concentration of the 5-HT uptake blockers (10 microM). In the additional presence of the MAO inhibitors or nomifensine (which by themselves increased or diminished, respectively, the [3H] labelling) the 5-HT uptake inhibitors became more potent in reducing the percentage [3H]-5-HT accumulation of caudate nucleus slices. These results indicate (1) that a false labelling of [3H]-5-HT into dopaminergic terminals in the caudate nucleus can be prevented by nomifensine, (2) that the 5-HT uptake blockers seem to accumulate within the dopaminergic terminals, where they may display a MAO inhibitory property. The 5-HT uptake blockers were ineffective on the percentage tritium accumulation of caudate nucleus slices incubated with [3H]-DA, regardless of the presence of pargyline or nomifensine. Tritiated DA and deaminated [3H]-metabolites were separated in the superfusate of [3H]-DA-release experiments in caudate nucleus tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-depressive treatment in Parkinson's disease. A controlled trial of the effect of nortriptyline in patients with Parkinson's disease treated with L-DOPA

Nineteen patients with L-DOPA treated parkinsonism involving depressive symptoms, the therapeutic effect of nortriptyline was compared to placebo in a controlled trial. The depressive and neurological symptoms were evaluated by rating scales. Nortriptyline had a clinical significant effect with regard to the depressive symptoms, whereas the neurological parameters were unchanged. The authors suggest the depression in Parkinson's disease to be of both reactive and endogenous origins.

Effect of neuroleptics and tricyclic antidepressants upon d-amphetamine discrimination

After rats were trained to differentiate between the effects of intraperitqoneal administration of 0.6 mg/kg d-amphetamine and saline, pretreatment with various neuroleptic drugs was observed to significantly inhibit d-amphetamine discrimination. Thus, trifluoperazine, haloperidol, fluphenazine, chlorpromazine and thioridazine, but not clozapine, decreased d-amphetamine-induced control of discriminative performance. The ED50s of the effective neuroleptics for this inhibition were similar to those reported for antagonism of amphetamine-induced stereotypic behavior in the rat and the slopes of the dose-response curves were parallel indicating a common site and mechanism of action, presumably blockade of postsynaptic dopaminergic receptors. In contrast, pretreatment with the tricyclic antidepressant agents, imipramine, nortryptiline and desipramine had no significant effect on the discrimination of a dose of d-amphetamine which produced a low degree of discriminative control. The results are viewed in relation to the "dopamine hypothesis" of schizophrenia and affective disorders and the use of this animal behavioral method for determining brain dopamine interactions is discussed.

Effects of thymoleptics on behaviour associated with changes in brain dopamine. I. Potentiation of dopa-induced gnawing of mice

The thymoleptics imipramine, desipramine, protriptyline, nortriiptyline, chlorimipramine and amitriptyline all potentiate gnawing of mice induced by Dopa following decarboxylase inhibitior Ro 4-4602. The gnawing behavior is probably associated with the increase in brain dopamine resulting from this treatment. Thymoleptics also affect other types of behaviour associated with brain dopamine. The relevance of these effects to clinical antidepressive effect and their possible utilization for preclinical screening tests is discussed.