The designer stimulant 4-methylmethcathinone (mephedrone) is among the most popular of the derivatives of the naturally occurring psychostimulant cathinone. Mephedrone has been readily available for legal purchase both online and in some stores and has been promoted by aggressive Web-based marketing. Its abuse in many countries, including the United States, is a serious public health concern....
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 effects of 3,4-dihydroxymethamphetamine (DHM) and 2,4,5-trihydroxymethamphetamine (THM) on central serotonergic and dopaminergic systems were investigated to determine if these metabolites share the neurochemical properties of 3,4-methylenedioxymethamphetamine. THM (50-200 micrograms) or DHM (135 micrograms) was administered i.c.v. to rats; 5 days later, cortical, striatal and hippocampal...
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...
Abstract: The activity of tryptophan hydroxylase (EC 1.14.16.4) from rat brain was significantly decreased 1 h following a single systemic injection of 3,4‐methylenedioxy‐methamphetamine (MDMA) when assessed ex vivo by ra‐dioenzymatic assay or in vivo by the quantitation of 5‐hy‐droxytryptophan accumulation following central L‐aromatic amino acid decarboxylase inhibition. Recovery of enzymatic...
Similar to other amphetamine analogs 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy"), a currently popular illicit drug, has been characterized recently as a serotonergic neurotoxin due to its ability to cause long-lasting deficits in markers of central serotonergic function in animals. Because the serotonergic toxicity associated with the MDMA analog methamphetamine has been linked...
This study demonstrates that the isomers of 3,4-methylenedioxyamphetamine (MDA) and 3,4-methylenedioxymethamphetamine (MDMA) are different in their ability to induce changes in serotonergic parameters and nigral concentrations of neurotensin-like immunoreactivity. With five successive doses (3.5 mg/kg) the d-MDA isomer was more potent than the l-MDA in its ability to decrease the concentrations...
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...
In the rat, administration of the psychoactive analog of amphetamine 3,4-methylenedioxymethamphetamine (MDMA), causes selective, pronounced decreases in markers of central serotonergic function. The time course of these neurochemical changes was examined in several serotonergic nerve terminal regions of the brain. Fifteen min after subcutaneous injection of MDMA (10 mg/kg), the enzymatic...
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...
The effects of two amphetamine-like designer drugs, 3,4-methylenedioxyamphetamine (MDA) and 3,4-methylenedioxymethamphetamine (MDMA), on dopaminergic and serotonergic systems in the rat brain were investigated and compared to those of methamphetamine (METH). Like METH, single or multiple 10 mg/kg doses of either drug caused marked reductions in both tryptophan hydroxylase (TPH) activity and...