Brain tryptophan hydroxylase activity decreases within 15 min after a single administration of 3,4-methylenedioxymethamphetamine. In the present study, the effect of body temperature on this acute decrease of tryptophan hydroxylase activity was examined. 2 h after a single dose of 3,4-methylenedioxymethamphetamine (20 mg/kg, s.c.), rats exhibited hyperthermia (38.7 degrees C) or hypothermia...
The concentration of serotonin (5-HT) measured in rat striatum was reduced to 75% of control 1 week after a single subcutaneous administration of dl-3,4-methylenedioxymethamphetamine (MDMA, 20 mg/kg). This decrease was prevented by pretreating the animals with ritanserin. Eighteen hours after MDMA (20 mg/kg), striatal concentrations of neurotensin-like immunoreactivity (NTLI) and of dynorphin...
The long-term effects of three metabolites of 3,4-methylenedioxymethamphetamine (MDMA) on the central monoaminergic systems of the rat were examined. Seven days after the intracerebroventricular administration of 0.25 and 0.5 mumol 2,4,5-trihydroxyamphetamine, hippocampal tryptophan hydroxylase (TPH) activity was reduced to 5 and 1% of control, respectively, while norepinephrine (NE)...
The effect of calcium channel blockers on the decrease in central tryptophan hydroxylase (TPH) activity and serotonin (5-HT) concentration induced by repeated large doses of methamphetamine (METH) or 3,4-methylenedioxymethamphetamine (MDMA) was evaluated. Rats received four or five injections of METH (10 or 15 mg/kg) or MDMA (10 mg/kg) at 6-h intervals, and were sacrificed 18 to 20 h or 1 week...
The influence of N-ethyl-3,4-methylenedioxyamphetamine (MDE) on the central serotonergic and dopaminergic systems of the rat after a single or multiple injections was studied. MDE (10 mg/kg) produced a significant decrease in the concentration of 5-hydroxytryptamine (5-HT) 1 hr later in the frontal cortex and the hippocampus without affecting the concentration of 5-hydroxyindoleacetic acid...
Three psychoactive amphetamine congeners were evaluated for their ability to cause long-term changes in several neurochemical parameters indicative of central serotonergic function. Two weeks after multiple doses (10 mg/kg) of 3,4-methylenedioxyamphetamine (MDA) or its N-methylated derivative, 3,4-methylenedioxymethamphetamine (MDMA), selective and dramatic decreases were observed in regional...