The effect of pargyline and desmethylimipramine on monoamine concentrations and amphetamine-induced glycogenolysis in the mouse brain

Systemic d-amphetamine administration causes a reduction of kynurenic acid levels in rat brain

Tissue levels of the endogenous excitatory amino acid receptor antagonist kynurenic acid (KYNA) and of its bioprecursor L-kynurenine were measured in rats of different ages after d-amphetamine administration. In adult animals, extracellular KYNA concentrations were also determined in vivo by hippocampal microdialysis. In the adult brain, d-amphetamine caused a transient, dose-dependent decrease in tissue content and extracellular levels of KYNA, reaching a nadir of approximately 70% of control values after 1 h at 5 mg/kg. Quantitatively similar decrements were observed in four different brain regions. Seven, 14 and 28-day-old pups were particularly sensitive to the drug, showing a reduction in forebrain KYNA levels to 25%, 40% and 35% of control values, respectively, 1 h after the administration of 5 mg/kg d-amphetamine. Notably, no changes in brain L-kynurenine levels and in liver L-kynurenine and KYNA concentrations were found after d-amphetamine administration. Thus, endogenous monoamines released by d-amphetamine may interfere with the transamination of L-kynurenine to KYNA specifically in the brain. These results suggest that d-amphetamine increases excitatory amino acid receptor function temporarily by reducing the levels of endogenous KYNA.

Changes in body temperature after administration of adrenergic and serotonergic agents and related drugs including antidepressants

This survey, the third in a series, presents extensive tabulations of literature, primarily since 1965, on thermoregulatory effects of adrenergic and serotonergic agonists and their antagonists including ergot alkaloids, amphetamines, tryptamines, monoamine oxidase inhibitors, tricyclic and other antidepressants, a variety of other agents which alter presynaptic aminergic mechanisms including reserpine, 6-hydroxydopamine, p-chlorophenylalanine, alpha-methyltyrosines, cocaine, guanethidine and bretylium. The information listed includes the species used, route of administration and dose of drug, the environmental temperature at which the experiments were performed, the number of tests, the direction and magnitude of body temperature change and remarks on the presence of special conditions, such as age or lesions, or on the influence of other drugs, such as antagonists, on the response to the primary drug.