The acute effects of amphetamine derivatives on extracellular serotonin and dopamine levels in rat nucleus accumbens.

The acute effects of amphetamine derivatives on extracellular concentration of serotonin (5-HT) and dopamine in the nucleus accumbens were studied with in vivo microdialysis using conscious, freely moving rats. 5-HT, dopamine, and their major metabolites were measured by HPLC with electrochemical detection. Amphetamine (1.

Effects of alcohol, zolpidem, and some other sedatives and hypnotics on human performance and memory.

Zolpidem (Zol), an omega1-agonist, acts via GABA(A) receptors but may differ qualitatively from diazepam (Dz) and other benzodiazepines (BZDs). We conducted a placebo-controlled, randomized, double-blind, and crossover study to compare the psychomotor and cognitive effects of 15 mg Zol with those of 15 mg Dz, 30 mg oxazepam (Ox), 7.5 mg zopiclone (Zop), and ethanol (EOH; 0.

Heat exposure and drugs. A review of the effects of hyperthermia on pharmacokinetics.

Acute heat loading is encountered in several everyday situations, during physical exercise or work in a hot climate are just 2 examples. Special forms of heat exposure include different types of steam baths and saunas. External heating induces changes in haemodynamics, body fluid volume and blood flow distribution, which in turn may affect the pharmacokinetics of a drug and the therapeutic response.

Pharmacokinetics and ventilatory effects of oxycodone before and after liver transplantation.

The pharmacokinetics and ventilatory effects of oxycodone were studied in six volunteer patients with end-stage liver cirrhosis before and after orthotopic liver transplantation. Plasma samples and urine were collected for 24 hours after intravenous administration of 0.05 mg/kg oxycodone hydrochloride.

Renal excretion of tetracycline is transiently decreased during short-term heat exposure.

Renal blood flow is known to be reduced during intensive external heating, which may have clinical relevance for renal drug elimination as well. The effects of heat exposure in a sauna bath on tetracycline pharmacokinetics were studied in 8 healthy volunteers in an open, randomized crossover study. The subjects were given a single oral dose of tetracycline (500 mg) both in a control session and in a sauna bathing session.

Pharmacokinetic comparison of intravenous and intranasal administration of oxycodone.

Background: For patients with chronic pain, treatment with oral analgesics is considered most convenient and feasible. Sometimes, however, the oral route cannot be used because of difficulties with swallowing, nausea, vomiting and gastrointestinal obstruction. To investigate the applicability of the nasal route for the administration of oxycodone, we studied the intravenous and intranasal pharmacokinetics of oxycodone in healthy volunteers.

Comparison of RapiTest with Emit d.a.u. and GC-MS for the analysis of drugs in urine.

Results obtained with RapiTest THC (One Step delta 9-Tetrahydrocannabinol Test), RapiTest MOP (One Step Morphine Test), RapiTest MET (One Step Methamphetamine Test), and RapiTest COC (One Step Cocaine Test) were compared with the results obtained with Emit d.a.u.

High doses of alcohol increase urinary testosterone-to-epitestosterone ratio in females.

The effect of alcohol (1.2 and 2.0 g/kg) on the urinary testosterone-to-epitestosterone (T/E) ratio was studied by two experiments each conducted with four healthy females and males.

The effects of midazolam and ephedrine on post-exercise autonomic chronotropic control of the heart in normal subjects.

Benzodiazepines may induce hypotension by inhibiting the pressor response. Ephedrine has adrenergic effects on the circulation. After exercise, changes in cardiovascular control impair orthostatic tolerance.

Exposure to high ambient temperature increases absorption and plasma concentrations of transdermal nicotine.

Absorption and plasma concentrations of transdermally delivered drugs may be increased during heat exposure. We studied the effects of short-term heat exposure in a sauna bath on the pharmacokinetics of transdermal nicotine, 25 mg/16 hr, in 12 healthy smokers in an open, randomized crossover study that consisted of a control session and a sauna bathing session. In the sauna session the subjects stayed seated in a sauna bath (mean temperature 82 degrees C (180 degrees F); mean relative humidity 28%) for three 10-minute periods separated by two 5-minute breaks.

The effects of anabolic androgenic steroids on serum ubiquinone and dolichol levels among steroid abusers.

We measured serum ubiquinone and dolichol concentrations in 13 men while they abused anabolic androgenic steroids (AAS) and during the following withdrawal period. Serum total, high-density lipoprotein (HDL), and low-density lipoprotein (LDL) cholesterol and triglycerides were also determined. AAS administration increased serum ubiquinone by 68% (P < .

5-HT3 receptor antagonist MDL 72222 dose-dependently attenuates cocaine- and amphetamine-induced elevations of extracellular dopamine in the nucleus accumbens and the dorsal striatum.

The effects of a 5-HT3 receptor antagonist MDL 72222 on cocaine- and amphetamine-induced increases in extracellular dopamine in the nucleus accumbens and the dorsal striatum were studied with microdialysis technique using halothane anaesthesized rats. Dopamine and its metabolites were measured by HPLC with electrochemical detection. Cocaine elevated extracellular dopamine in the nucleus accumbens and to a lesser extent in the dorsal striatum, but it did not affect dopamine metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid.

Comprehensive drug screening in blood for detecting abused drugs or drugs potentially hazardous for traffic safety.

A comprehensive drug screening procedure for detecting drugs in the blood samples of car drivers suspected of driving under the influence of drugs, is presented. Amphetamines, cannabinoids, opioids, cocaine and benzodiazepines were screened by an immunological EMIT ETS system after acetone precipitation. Gas chromatographic methods were used to screen and quantitate basic, neutral and acidic drugs.

Exposure to high environmental temperature in the sauna does not change plasma indocyanine green (ICG) clearance in healthy subjects.

Indocyanine green (ICG) was given intravenously (0.5 mg kg-1) to seven healthy male volunteers in random order during a control session and a session in the sauna bath. The sauna bathing session consisted of three 10 min.

The pharmacokinetics of oxycodone in uremic patients undergoing renal transplantation.

Study Objective: To determine the pharmacokinetics of oxycodone and the excretion of oxycodone and its metabolites noroxycodone and oxymorphone in uremic patients undergoing renal transplantation.

Design: Open study of the pharmacokinetics and excretion of oxycodone.

Setting: IV Department of Surgery, Helsinki University Central Hospital.

Drugs usage of drivers suspected of driving under the influence of alcohol and/or drugs. A study of one week's samples in 1979 and 1993 in Finland.

The extent of drug use among drivers suspected of driving under the influence of alcohol and/or drugs in Finland was studied. All blood samples submitted to the laboratory during 1 week in two study periods, in 1979 (n = 298) and 1993 (n = 332), were analyzed for alcohol and psychotropic drugs. Drugs classified as hazardous to traffic safety were detected in 7.

Taurine infused intrastriatally elevates, but intranigrally decreases striatal extracellular dopamine concentration in anaesthetised rats.

In the present study we infused taurine (50, 150 or 450 mM, 2 microliters/min for 4h) into the dorsal striatum or into the substantia nigra via microdialysis probe and estimated the extracellular concentrations of dopamine and its metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), in the dorsal striatum of anaesthetised rats. Intrastriatal infusion of taurine elevated striatal dopamine at all concentrations studied. At the 450 mM concentration taurine elevated the extracellular dopamine 10-fold, but only in the first 30 min sample after starting the taurine infusion.

Effects of heat exposure in a Finnish sauna on the pharmacokinetics and metabolism of midazolam.

Objective: The effect of short-term heat exposure in a Finnish sauna on hepatic first-pass metabolism and the capacity to metabolize midazolam were studied in a crossover trial. Midazolam oral (15 mg) and intravenous (0.05 mg.

Single oral doses of amisulpride do not enhance the effects of alcohol on the performance and memory of healthy subjects.

Objectives: Amisulpride is a benzamide antipsychotic that binds selectively to dopamine D2- and D3-receptors, preferentially in limbic and hippocampal structures. Since other substituted benzamides have a limited or negligible interaction with alcohol on human performance, amisulpride was studied for this potential.

Methods: In a randomised double-blind crossover study, 18 young, non-smoking men took single oral doses of placebo and amisulpride 50 mg and 200 mg, without and with ethanol (0.

Grapefruit juice does not enhance the effects of midazolam and triazolam in man.

Objectives: Since grapefruit juice (Gra) inhibits hepatic P450 (CYP3A4), we studied its potential to enhance the effects of midazolam (Mid) and triazolam (Trz), which are metabolized by the CYP3A4 isoenzyme.

Methods: In Study I parallel groups of healthy students were given orally Mid 10 mg with water or grapefruit juice (GraMid), two placebo groups receiving water or Gra. The effects of Mid were measured by psychomotor tests and by self-rating on visual analogue scales before and 30 and 90 min after intake.

The effects of ethanol in combination with the alpha 2-adrenoceptor agonist dexmedetomidine and the alpha 2-adrenoceptor antagonist atipamezole on brain monoamine metabolites and motor performance of mice.

The time course of the effects of ethanol alone and in combination with the selective alpha 2-adrenoceptor agonist dexmedetomidine and the alpha-adrenoceptor antagonist atipamezole was studied in NIH-Swiss mice. Core body temperature, rotarod performance, motility and changes in the noradrenaline, dopamine, and 5-hydroxytryptamine (5-HT) metabolite contents of different brain parts (limbic forebrain, striatum, lower brainstem, the rest of the forebrain + midbrain and hypothalamus) were measured. Atipamezole (3 mg/kg) attenuated the hypothermia induced by either ethanol (3 g/kg) alone or ethanol in combination with dexmedetomidine (0.

CSF concentrations and clinical effects following intravenous dixyrazine premedication.

Single concurrent plasma and lumbar spinal fluid samples were collected from twenty-two patients given IV dixyrazine 0.15 mg/kg, 10-106 min earlier in an open study. Dixyrazine penetrated rapidly into the spinal fluid; the CSF/P ratio was 0.

Effects of a Finnish sauna on the pharmacokinetics and haemodynamic actions of propranolol and captopril in healthy volunteers.

The effects of a Finnish sauna on propranolol pharmacokinetics and on the pharmacodynamics of propranolol and captopril were studied in healthy, young volunteers (2 males, 6 females) in a double-blind, cross-over trial. The subjects received single oral doses of placebo, propranolol (40 mg) or captopril (12.5 mg) in sauna and control sessions at a one-week interval.

Antinociceptive actions of dexmedetomidine and the kappa-opioid agonist U-50,488H against noxious thermal, mechanical and inflammatory stimuli.

The antinociceptive efficacies of both intrathecally (i.t.) and systemically administered dexmedetomidine (a selective alpha-2 adrenoceptor agonist) and U-50,488H [trans(+/-)-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)-cyclohexyl]- benzene-acetamide] (a kappa-opioid receptor agonist) were studied during peripheral inflammation induced by carrageenan.