Biomedical subjects

L Aanderud

Publications and source records attributed to L Aanderud.

28 records · Page 2Linked to original sources

PubMed1983

Tissue distribution of thiopental and diazepam in rats at 71 atmospheres pressure.

35S-thiopental 15 mg/kg and 14C-diazepam 5 mg/kg were injected intravenously in separate groups of rats (n = 6) at 1 ATA air and at 71 ATA air-He. Total radioactivity was measured in the brain, liver, kidney, muscle and fat after 1, 3, 5 and 15 min. The thiopental content was significantly reduced at pressure in the brain at 3, 5 and 15 min. The diazepam content of the brain was significantly reduced at pressure at 1, 5 and 15 min. The liver, muscle and kidney tissue generally contained slightly less of either drug at pressure, particularly at the earliest sampling times.

Animals↗

PubMed1983

Pharmacokinetics of antipyrine, paracetamol, and morphine in rat at 71 ATA.

The pharmacokinetics of [14C]antipyrine, [3H]paracetamol, and [3H]morphine were studied in male Wistar rats at 1 ATA and then at 71 ATA, each animal being its own control. Separate control groups were studied at 1 ATA in order to test the validity of the one-way crossover protocol. The drugs were injected through a femoral venous catheter, and blood was sampled from a catheter in the femoral artery. There were no significant differences in the biological half-life (T1/2), the apparent volume of distribution (Vd), and the clearance (C) of antipyrine and paracetamol. Likewise, there was no appreciable effect of high pressure on the blood concentration profile of morphine.

Acetaminophen↗

PubMed1982

Effect of high pressure on EEG burst suppression dose of thiopental in rats.

The anesthetic induction dose of thiopental in rats was studied at 1 ATA air, 1 ATA helium-oxygen (He-O2), 4 ATA air, and at 4 ATA air plus 67 ATA helium (71 ATA). The compression rate was 0.3 ATA/min, and 1 h was spent at pressure before the experiment started. Thiopental was infused at a rate of 7.5 mg X kg-1 X min-1. The depth of anesthesia was assessed by electroencephalographic (EEG) recording using burst suppression of 1 s as the biological end point. The mean induction dose at 1 ATA air was 53.1 mg/kg and at 71 ATA was 74.7 mg/kg, an increase of 41%. The induction doses at 1 ATA He-O2 and 4 ATA air were 46.4 mg/kg and 45.3 mg/kg, respectively.

Animals↗

PubMed1981

A system for pharmacological studies in small animals at high pressure.

A four-liter pressure chamber was constructed for pharmacological experiments in rats; it consisted of the following: 1) a system for repeated, accurate injection; 2) an alternative single-dose injection system; 3) a system for direct blood sampling to the outside. The injection and sampling systems were tested for possible drug adsorption at 71 ATA. The accuracy of drug concentration measurements in samples collected through the sampling system at pressure was found to be satisfactory.

Animals↗

PubMed1980

Enteric coated quinidine compared to sustained release preparations during repeated administration.

The concentration of quinidine in plasma was measured in 12 healthy subjects during multiple administration of an enteric coated tablet (Systodin) and two sustained release preparations (Kinidin Duretter and Kinilentin). In a second study, involving another 12 subjects, the enteric coated tablet and the most widely used sustained release preparation (Kinidin Duretter) were compared with plain uncoated quinidine sulphate tablets in order to calculate the relative bioavailability of the formulations used for maintenance therapy. The largest area under the plasma concentration-time curve (AUC12h) during a dosage interval (12 hours) was obtained with the plain tablets and with the enteric coated formulation. The variation of the plasma concentrations during the dosage interval was not larger with the enteric coated tablets than with the sustained release preparations. The time of appearance of peak concentration after administration was longer and more variable with the enteric coated tablets. In relation to the plain quinidine tablets, the bioavailability of Systodin and Kinidin Duretter was 96% and 84%, respectively. In 21 out of 24 crossover experiments with Kinidin Duretter and Systodin the AUC12h was larger with the latter formulation. Enteric coating appears to be a simple and reliable means of achieving delayed absorption and stable quinidine plasma levels during maintenance therapy.

Adult↗

PubMed1980

Drug absorption during physical exercise.

1 The effect of exercise on the absorption of quinidine sulphate, sodium salicylate and sulphadimidine was studied in healthy volunteers. 2 The study was a randomized cross-over design with work and rest. The work load was 450 kpm/min for females and 600 kpm/min for males on a bicycle ergometer intermittently for 3 h. 3 The plasma concentrations of the drugs were followed during the entire experiment and their respective peak concentrations (Cmax) and time to peak (tmax) were determined. 4 No significant differences in the Cmax and tmax were found between rest and work for any of the drugs. 5 The results suggest that physical exercise is not a major source of variation in drug absorption.

Adult↗

PubMed1979