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Biomedical subjects

H Koenig

Publications and source records attributed to H Koenig.

At least 73 records · Page 4Linked to original sources
PubMed1980

Androgens regulate mitochondrial cytochrome c oxidase and lysosomal hydrolases in mouse skeletal muscle.

The gastrocnemius, a fast-twitch white muscle, and the soleus, a slow-twitch red muscle, were studied in A/J mice. The specific activities of the lysosomal hydrolases, beta-D-glucuronidase, hexosaminidase, beta-D-galactosidase and arylsulphatase, the inner-mitochondrial-membrane enzyme cytochrome c oxidase, and the outer-mitochondrial-membrane enzyme monoamine oxidase, were greater in the soleus than in the gastrocnemius. The specific activities of the lysosomal hydrolases and cytochrome c oxidase in the gastrocnemius and soleus were substantially higher in male mice than in female mice. Orchiectomy abolished this sex difference. Testosterone increased the activities of the lysosomal hydrolases and cytochrome c oxidase and coincidentally induced muscle hypertrophy and an accretion of protein and RNA, but total DNA remained constant. Monoamine oxidase was unaffected by sex, orchiectomy and testosterone. These findings indicate that endogenous androgens regulate the activity of enzymes associated with lysosomes and the inner mitochondrial membrane, as well as muscle fibre growth in mouse skeletal muscle.

Animals↗
PubMed1980

Testosterone-mediated sexual dimorphism of mitochondria and lysosomes in mouse kidney proximal tubules.

In kidney proximal tubules of male mice the mitochondria are larger and more electron-lucent, autophagic vacuoles and lysosomes (predominantly myeloid bodies) more numerous and voluminous, and exocytosed intraluminal myeloid bodies more common than in females. Males also have higher kidney activities of mitochondrial cytochrome c oxidase and lysosomal hydrolases, and excrete larger quantities of hydrolases and protein in the urine. Orchiectomy evokes the feminine pattern whereas testosterone administration induces the male pattern. Endogenous testosterone modulates mitochondrial structure and function and enhances the activity of the lysosomal-vacuolar system in proximal tubule cells.

Animals↗
PubMed1979

[Molecular forms of acetylcholinesterase in the chicken ciliary ganglion; changes after denervation, axotomy and double section].

Four main molecular forms of acetylcholinesterase (AChE), with sedimentation coefficients of 5, 7.5, 11.5 and 20 S, are found in Chicken ciliary ganglion. After denervation, the loss in 11.5 and 20 S forms occuring in 48 hrs coincides with the disappearance of presynaptic structures. In contrast, axotomy induces an early and durable increase in 7.5 S form. From these results, it is inferred that 11.5 and 20 S forms are predominant in presynaptic structures and 7.5 S form is mainly postsynaptic. In addition, the effects observed after simultaneous denervation and axotomy show a reciprocal control between pre- and postsynaptic elements. Finally, a trans-synaptic effect is exerted on 20 S AChE in controlateral ganglion after preganglionic sections.

Acetylcholinesterase↗
PubMed1977

Lysosomal enzyme secretion in rat ventral prostate. Secretagogue action of testosterone and dibutyryl cyclic AMP.

Rat ventral prostate slices, when incubated in vitro, secrete protein, lysosomal enzymes and newly phosphorylated components in a time- and temperature-dependent manner. Testosterone and dibutyryl cyclic AMP immediately stimulate secretion and 32Pi incorporation. Acid phosphatase and beta-N-acetylhexosaminidase are secreted as acidic isoenzymes presumably contained within primary lysosomes.

Acid Phosphatase↗
PubMed1976

Testosterone and 6-N,2'-O-dibutyryladenosine 3':5'-cyclic monophosphate stimulate protein and lysosomal enzyme secretion in rat seminal vesicle.

Rat seminal-vesicle secretion was studied in vitro in a slice-incubation system. Seminal-vesicle slices were preincubated with 32Pi for 15 min, rinsed, and incubated in an isotope-free 'chase' medium for up to 4h. Gland slices spontaneously discharged protein, three lysosomal hydrolases and trichloroacetic acid-insoluble 32P into the medium in a time- and temperature-dependent manner. Testosterone (10 muM) and dibutyryl cyclic AMP (1 mM) stimulated the discharge of protein, acid hydrolases and trichloroacetic acid-insoluble 32P, and also stimulated the incorporation of 32Pi into trichloroacetic acid-insoluble components. The acid phosphatase and beta-N-acetylhexosaminidase isoenzymes were separated by isoelectric focusing. These hydrolases were secreted into the medium as acidic isoenzymes, presumably contained within primary lysosomes, whereas they occurred largely as less acidic and basic isoenzymes in the glandular tissue.

Acid Phosphatase↗
PubMed1976

[Cholegraphy with protracted mechanical infusion as a method of routine].

250 out-patients were examined by mechanical 30 min slow-infusion cholegraphy with 20 ml jodipamide (Adipiodon). Only 1.2% slight and 2.0% distinct side effects were established. The frequency and severity of these reactions were less compared with the usual intravenous cholecystography. The described method of investigation may be recommended for use.

Abdomen, Acute↗
PubMed1976

Autophagy-related changes of arylsulphatases A and B in rat liver lysosomes.

The total arylsulphatase activity and the relative activities of lysosomal arylsulphatases A and B were measured in the liver of control rats and rats subjected to treatments that provoke hepatic autophagocytosis. The total liver arylsulphatase activities were increased in starved and starved glucagon-treated rats, but not in sham-operated and hepatectomized rats. Arylsulphatases A and B in the mitochondrial-lysosomal (M-L) fraction were separated by polyacrylamide-gel electrophoresis at pH 8.8; they were made visible by incubating the gels with p-nitrocatechol sulphate as substrate, and measured by quantitative densitometry. In untreated controls, arylsulphatases A and B comprised 41.4 +/- 0.5% and 58.6 +/- 0.5% of the total arylsulphatase activity respectively; the arylsulphatase A/arylsulphatase B activity ratio was 0.71. All experimental treatments produced a significant decrease in the percentage of lysosomal arylsulphatase present as the A form and an increase in that present as the B form, and the activity ratio of arylsulphatase A/arylsulphatase B declined. The magnitude of these changes increased in the following direction: starvation for 24h=sham hepatectomy less than glucagon + starvation less than subtotal hepatectomy. These results indicate that the arylsulphatase A/arylsulphatase B activity ratio in liver lysosomes of normal rats is maintained within rather narrow limits, and this ratio declines during enhanced autophagocytosis. These findings, together with observations that suggest that arylsulphatase B may be a partially degraded form of arylsulphatase A, are consistent with the view that the A form is more rapidly converted into the B form during autophagy, owing to the digestive activity of the other lysosomal hydrolases present in autophagic vacuoles.

Animals↗