[The effect of neurotropic preparations on the sensitivity of the hypothalamo-hypophyseal system to the inhibiting action of dexamethasone].

The effect of 10 neurotropic drugs with the known mechanism of action on the cortisol level was studied in 220 patients with effective psychoses before and after administration of 0.5 mg of dexamethasone. The use of the tranquilizer phenazepam, alpha-adrenoblockers pyrroxane and phentolamine and a new generation antidepressant mianserin blocking alpha-adrenoreceptors, improved considerably the results of a dexamethasone test. Pharmacological enhancement of serotoninergic processes with alpha-tryptophan either increased or decreased the inhibitory effect of dexamethasone with relation to the initial response to glucocorticoid administration. Dopamine-mimetics alpha-DOPA and bromocriptine improved the results of the test in patients who were resistant to dexamethasone action before the initiation of therapy. Disorder of the homeostatic regulation of corticosteroid secretion of feed-back type is mainly caused by chronic stress and increased influence of noradrenaline on alpha-adrenoreceptors of the cerebral structures responding to feedback signals. Serotonin- and dopamine-mimetics make a normalizing effect on the mechanism of self-regulation of glucocorticoid secretion.