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E Fischer

Publications and source records attributed to E Fischer.

At least 271 records · Page 15Linked to original sources
PubMed1979

[Time-dependent changes in the lactic acid level of ischemic muscle tissue under conditions of arterial embolism, simulated in animal experiments].

It may be summarized that under the condition of embolism in animal experiments the lactate level is significantly changed depending on the duration of ischemia. Thus, for judgement of a hypoxic damage of muscle tissue this parameter appears to be useful. A more precise analysis would be imaginable, when the degree of tissue damage could be stated according to a certain lactate level. For this, however, the reported results must be compared with a randomized series of human patients suffering from arterial embolism, since the present studies concern the muscles of rats.

Animals↗
PubMed1979

Hepatic storage and biliary excretion of rose bengal in the rat.

The distribution of intravenously administered rose bengal (RB) depends on its dose. At a low dose (10 mg/kg), RB can be found almost solely in the liver and plasma. However, at higher doses (from 25 up to 200 mg/kg) the amount of RB found in extra-hepatic tissues gradually increases. In this experiment the hepatic transfer maximum of RB amounted to 146 micrograms/kg/min. By increasing the dose from 10 to 200 mg/kg, the hepatic concentration of RB also approached a maximum (1250 micrograms/g). The storage capacity of the liver, however, did not limit the transfer maximum of RB.

Animals↗
PubMed1979

Correlation between hepatic transport of cholephilic organic anions and their effect on hepatic mitochondrial respiration.

The maximum biliary excretion rate (Tm) of some nonmetabolized organic anions was investigated in anaesthetized male rats and was found to increase in the following order: indocyanine green (ICG), rose bengal (RB), bromsulphthalein (BSP; its conjugation with glutathione was prevented by diethyl maleate), bromcresol green (BCG), eosine (E), BSP-glutathione conjugate (BSP-GSH), iodoxamic acid (IA) and amaranth (A). The accumulation of ICG, RB, BSP and BCG in liver was relatively high, whereas E, BSP-GSH,IA and A were taken up by the liver in a lower concentration. ICG, RB, BSP and BCG decreased the biliary flow, however, E, BSP-GSH, IA and A stimulated it. ICG, RB and BSP had a strong, BCG and E a moderate, inhibitory effect on hepatic mitochondrial respiration stimulated by ADP, DNP and glutamate-malate, whereas BSP-GSH, IA and A had no effect on this process. Our results suggest that the depressing effect of cholephilic organic anions on bile production and their low biliary excretion rates are connected with their inhibitory effects on mitochondrial respiration.

Amaranth Dye↗
PubMed1979

Hepatic microsomal induction and hepatic transport.

Hepatic microsomal induction (hexobarbital sleeping time, cytochrome P-450 and microsomal protein concentration, liver weight) and hepatic transport (hepatic uptake, biotransformation, biliary excretion) have been studied in rats. Phenobarbital pretreatment (75 mg/kg i.p. daily for 5 days) produced microsomal induction in the liver and enhanced biliary excretion of bromcresol green, eosine, bromsulphthaleine glutathione conjugate (BSP-GSH), amaranth and iodoxamic acid. However, biliary excretion of indocyanine green was unchanged after phenobarbital pretreatment. Biotransformation of bromsulphthalein (BSP) with glutathione was also increased by phenobarbital. The hepatic concentration of these organic anions was not influenced uniformly after phenobarbital pretreatment: the concentration of indocyanine green, bromcresol green, eosin and BSP-GSH in the liver was unchanged, that of amaranth and iodoxamic acid was enhanced following phenobarbital pretreatment. Investigation of the effect of pretreatment with other barbiturates showed that barbital, butobarbital, pentobarbital and amobarbital produced microsomal induction. Only baribtal and butobarbital stimulated biliary excretion of organic anions, whereas pentobarbital and amobarbital proved to be ineffective in this parameter. The results seem to indicate that the enhanced biliary excretion of exogenous organic anions produced by barbiturates is independent of microsomal enzyme induction.

Amaranth Dye↗
PubMed1978

Evidence of the presence of extraperoxisomal catalase in chloragogen cells of the earthworm, Lumbricus terrestris L.

The DAB reactivity of the midintestine of the earthworm, consisting of epithelial layer, muscle layer, and chloragogen tissue, was examined electron microscopically. Besides the mitochondrial membranes of the examined cell types and the hemoglobin content of the blood vessels and chloragogen cells, a considerable DAB reactivity was found in the whole cytosol of the chloragocytes. The DAB reaction of the cytosol was more intensive when incubation medium for catalase, less intensive when incubation medium for peroxidase, was used and did not occur when H2O2 was omitted. Cytosol of the chloragogen cells was isolated and preliminary assay of catalase and peroxidase activities was made. Cytosol samples showed moderate peroxidase activity, but catalase activity measured by the decomposition of hydrogen peroxide showed a very high rate. Catalase and peroxidase activities of the cytosol were heat-sensitive and might have been inhibited by azide and cyanide, respectively. Results prove the assumption that the intensive DAB reactivity of the chloragocyte cytosol is caused by its extraperoxisomal catalase content.

Animals↗
PubMed1978

Control of plasma aldosterone in diabetic patients with hyporeninemic hypoaldosteronism.

In three patients with diabetes and hyporeninemic hypoaldosteronism changes in renin activity, plasma aldosterone and cortisol were examined under various conditions: orthostasis and intravenous furosemide, infusion of synthetic beta1-24 ACTH on two consecutive days and diurnal variations in basal hormone fluctuations. Each patient showed unmeasurably low renin activity unresponsive to orthostasis and intravenous furosemide while plasma aldosterone was below normal range. Under ACTH-infusion only marked increases in aldosterone were observed in one patient whereas cortisol responded normally in all diabetics tested. Analysis of diurnal night day fluctuations (20.00-8.00) in plasma aldosterone and cortisol revealed a close and statistically significant relationship between both hormones in each of the three patients (p less then 0.05-less than 0.001). Variations in plasma aldosterone thus were mediated through changes in endogenous pituitary ACTH. Compared with normal controls however, diurnal aldosterone curves were set at a lower level. Our results demonstrate that a reduced sensitivity of the adrenal gland to ACTH is not responsible for the observed subnormal plasma aldosterone levels in these patients. Therefore, the lack of circulating angiotensin II seems to be the causative reason of hypoaldosteronism. The exact mechanism of undetectable renin activity in these patients remains unknown.

Adrenocorticotropic Hormone↗
PubMed1978

DOPA peroxidase activity in the chloragogen cells of the earthworm, Lumbricus terrestris L.

DOPA peroxidase activity of the cytosol of chloragocytes in the earthworm was proved by biochemical and histochemical methods, respectively. Chloragocyte DOPA peroxidase do not hydroxylate tyrosine, but it may oxidize besides DOPA other phenolie compounds in the presence of hydrogen peroxide. Probable participation of this enzyme in the detoxication of phenolie compounds and in the formation of chloragosomes was discussed.

Animals↗
PubMed1978

Pulvomycin, an inhibitor of protein biosynthesis preventing ternary complex formation between elongation factor Tu, GTP, and aminoacyl-tRNA.

Pulvomycin and the synonymous antibiotics labilomycin and 1063-Z are shown to inhibit prokaryotic protein synthesis by acting on elongation factor Tu (EF-Tu): in the presence of the antibiotic, the affinity of EF-Tu for guanine nucleotides is altered, the EF-Tu.GDP/GTP exchange is catalyzed, and the formation of the EF-Tu.GTP complex is stimulated. Hydrolysis of GTP by EF-Tu, induced by aminoacyl-tRNA, ribosomes, and mRNA or by kirromycin, is inhibited by pulvomycin. As shown by Millipore filtration, chromatographic analysis, and hydrolysis protection experiments, pulvomycin prevents interaction between aminoacyl-tRNA and EF-Tu.GTP to yield the ternary complex aminoacyl-tRNA.EF-Tu.GTP. Thus, enzymatic binding of aminoacyl-tRNA to ribosomes is blocked.

Aminoglycosides↗
PubMed1978

Bile flow and biliary excretion rate of some organic anions in phenobarbital-pretreated rats.

Bile flow and the biliary excretion of indocyanine green, bromcresol green, eosine, bromsulphthalein-glutathione conjugate (BSP-GSH), amaranth and iodoxamic acid were investigated in control and phenobarbital-pretreated rats (75 mg/kg i.p. daily for 5 days). The bile flow was increased by phenobarbital from an average of 50.6 to 77.7 microliter/kg/min. Depending on the dose, the biliary excretion rate of bromcresol green was increased by 48-496% and that of eosine by 30-149%. After phenobarbital pretreatment the excretion of BSP-GSH was also enhanced by 34-52%, that of amaranth by 37-53% and that of iodoxamic acid by 40-56%. However, the biliary excretion of indocyanine green remained unchanged. There was no parallelism between the increase in bile flow and biliary excretion of the drugs.

Amaranth Dye↗
PubMed1978

Hepatic transport of sulphobromphthalein and sulphobromphthalein-glutathione conjugate in control and phenobarbital-pretreated rats.

The biliary excretion of intravenously administered sulphobromphthalein (BSP) and sulphobromphthalein-glutathione conjugate (BSP-GSH) has been studied in control and phenobarbital-pretreated rats (75 mg/kg intraperitoneally daily for five days). Hepatic utake and biliary excretion of free BSP have been investigated in rats pretreated with diethyl maleate (DEM), which depletes the liver of glutathione (GSH) and therefore inhibits the conjugation of BSP with GSH. Phenobarbital pretreatment caused no significant change in the hepatic uptake of BSP or BSP-GSH. The conjugation of BSP and GSH in phenobarbital-preatreated rats was significantly faster than in the controls. The biliary excretion of free BSP was unchanged after phenobarbital induction, but significantly more BSP-GSH was excreted than in the controls. Thus, both the faster conjugation and the enhanced transport of BSP-GSH into the bile canaliculi were responsible for the increased biliary excretion of BSP in phenobarbital pretreated rats.

Animals↗
PubMed1978

Effect of Pb++ on Fe+++ tissue concentrations and delta-aminolaevulinic acid dehydratase activity in Lumbricus terrestris.

Iron was found at the highest concentration in the chloragogenous tissue with smaller amounts in the intestine and the lowest concentration in the body wall. Earthworms treated with Pb++ for 20 days showed a decrease in the concentration of Fe+++ in the intestinal tissue but no significant changes in the other tissue. The enzyme delta-aminolaevulinic acid dehydratase (ALAD) was not detected in isolated chloragosomes but it was found in the chloragocyte cytosol, body wall and intestine. L. terrestris treated with Pb++ showed a decrease in the activity of ALAD in all tissues where it was located and particularly in the chloragocyte cytosol.

Animals↗
PubMed1977

Cytochemical studies on the cuticle and epidermis of Tubifex tubifex Müll. with special regard to the localization of polysaccharides, heavy metals and the DAB-reactivity.

The cuticle consits of collagenous fibres and of two types of mucopolysaccharides. The whole cuticle contain PAS-positive polysaccharides, but the acid ones are localized only in the surface zone, both in the epicuticle and in the supracuticular mucoid coat. On the surface-damaged region of the cuticle bacterial infection was observed, those intact mucoid coat may be essential in protection against bacterial infection. Microvilli of the supporting cells play significant role in repairing of cuticular injuries. Acid mucopolysaccharides of the cuticle and epidermis may function as traps for heavy metals, proved by their significant heavy metal content. The cytosol of the epidermal cells possess considerable DAB-reactivity. The enzyme, responsible for the DAB-reaction, may be transported by the microvilli towards the cuticular surface and can play central role in the detoxication of organic foreign compounds.

3,3'-Diaminobenzidine↗