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I Bitsch

Publications and source records attributed to I Bitsch.

33 records · Page 2Linked to original sources
PubMed1989

[New methods for pharmacokinetic assessment of alcohol and its metabolites in male and female probands].

The pharmacokinetics of ethanol and its metabolites were examined in 10 young healthy women and men after 1-hr intravenous ethanol application of 7.8 mmol/kg body weight. Therefore, a new pharmacokinetic model takes into account Michaelis-Menten-elimination kinetics of ethanol as well as kinetics of acetaldehyde and acetate, which are defined by first order processes. The metabolite-model adequately describes the ethanol and acetate concentration courses. In fact, the observed ethanol concentrations are so close to the model-predicted values, that the metabolite-model allows an evaluation of half-life-times of acetaldehyde and acetate. The analyses of ethanol infusion studies showed, that there are no sex differences in parameters of ethanol elimination: Maximal elimination velocity Vmax was 3.41 +/- 0.61 mmol/l.h in females and 3.98 +/- 0.69 mmol/l.h in males. Michaelis-Menten-constant kM was 1.49 +/- 0.44 mmol/l and 1.69 +/- 0.88 mmol/l, respectively. In the female group, the volume of distribution of ethanol V1 was with 38.4 +/- 5.0 l significant smaller than in males with 50.5 +/- 3.5 l. In conclusion, the new metabolite-model can be used as a basis for the investigation of the entire alcohol metabolism.

Acetaldehyde↗
PubMed1978

[Enzyme-histochemical behaviour of the tanycyte ependyma in the III. ventricle of the rat with thiamin deficiency (author's transl)].

The influence of experimental thiamine deficiency in rats on enzyme-histochemical parameters was carried out in the diencephalon. The degree of thiamine deficiency was measured by the activity coefficient of transketolase in the red blood cells. The alpha-ETK of thiamine deficient animals was 1,45 +/- 0,36, of equal-fed animals 1,04 +/- 0.04 and of control animals 1,08 +/- 0,04. We got the following results: Lactatdehydrogenase, acid phosphatases and thiamine pyrophosphatase did not indicate any difference in enzyme activity between the groups of control, equal-fed and thiamine deficient rats. However, the enzyme activity of nonspecific lysosome-bound esterases in the tanycyte ependyma and in the investigated nuclear regions (nucleus supraopticus, ncl. paraventricularis, ncl. ventromedialis) of the thiamine deficient animals was significantly decreased in comparison to control and equal-fed animals. The possibility of a restriction of the hypophyseal-adrenal-cortex-system is discussed, since the results are similar to those obtained with bilaterally adrenalectomized rats.

Acid Phosphatase↗
PubMed1977

Peripheral nerve changes in thiamine deficiency and starvation. An electron microscopic study.

Electron microscopic investigations on sciatic and plantar nerves of thiamine deficient and starved rats show a distally pronounced axonal degeneration. The changes are present in starved and thiamine deficient animals, but the deficient animals are more severely affected. The earliest alterations consist of an increase of mitochondria and a proliferation of vesicular elements of the endoplasmic reticulum. They are followed by loop formations of the axon membrane, clustering and disintegration of neurotubules and neurofilaments, axonal shrinkage and finally myelin disruption. The distal accentuation of the early changes indicates a dying-back mechanism of axonal degeneration.

Animals↗
PubMed1976

Interactions between malnutrition and primaquine studied on Wistar rats. II. Complex vitamin B deficiency and thiamine deficiency.

The action of primaquine was investigated on male Wistar rats depleted on the vitamin B complex (approximately 50% of their requirement for optimal growth), on thiamine (approximately 50% of their requirement for optimal growth), and pair-fed control animals. There was only a marginal increase in adverse primaquine reactions in the malnourished, especially in the thiamine deficient rats.

Animals↗