A comparison of the effects of caffeine, 8-cyclopentyltheophylline, and alloxazine on sleep in rats. Possible roles of central nervous system adenosine receptors.

The dose-response effects of administration of 8-cyclopentyltheophylline (CPT) (10, 20, and 40 mg/kg intraperitoneally [IP]) and alloxazine (ALX) (12.5, 25, and 50 mg/kg, IP) on sleep and wakefulness in rats were examined and compared to those of caffeine (12.5 mg/kg IP).

Tolerance and cross-tolerance to 3,4-methylenedioxymethamphetamine (MDMA), methamphetamine and methylenedioxyamphetamine.

The effects of (+-)-3,4-methylenedioxymethamphetamine (MDMA) (0.62-20.0 mg/kg), (+)-methamphetamine (MA) (0.

The effects of a D1 and a D2 dopamine antagonist on behavior maintained by cocaine or food.

The purpose of the present experiment was to determine whether a D1 or a D2 dopamine antagonist could alter responding maintained by cocaine at doses that did not affect responding maintained by food. Rhesus monkeys were trained to press a lever in daily experimental sessions under a 3 component multiple schedule of reinforcement. In the first and third components, food was available under a fixed-ratio 30/time-out 2 min (FR30/TO 2) schedule.

Dose-response effects of 8-cyclopropyltheophylline on sleep and wakefulness in rats.

The dose-response effects of the substituted xanthine 8-cyclopropyltheophylline (CPRT) on sleep and wakefulness (W) after intraperitoneal administration to rats were examined by means of simultaneous electroencephalographic (EEG) and electromyographic (EMG) recordings. Doses of 20 and 40 mg/kg CPRT increased W and decreased slow wave sleep (SWS) in rats, indicating CNS stimulant effects. The greatest CNS stimulation was produced by the lowest (20 mg/kg) dose of CPRT examined, which also increased the latency to SWS.

Biochemical and histological evidence that methylenedioxymethylamphetamine (MDMA) is toxic to neurons in the rat brain.

(+/-)-3,4-Methylenedioxymethylamphetamine (MDMA) was administered s.c. to rats (10, 20 or 40 mg/kg b.