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W Haude

Publications and source records attributed to W Haude.

At least 19 recordsLinked to original sources
PubMed1992

[The effect of thyroid- and sex hormones on triglyceride secretion in rat liver].

The influence of thyroxine, estradiol and testosterone on the triacylglycerol (TG) secretion rate out of the liver into the blood as well as on concentrations of FFA, triglycerides, and glucose in serum was determined. All of these experiments were carried out under different nutritional conditions (non-fasting, and 10 or 16 h fasting, respectively). Accordingly the results after hormone application were compared with three groups of controls. Within these control groups increasing time of fasting caused exclusively an enhancement of FFA concentrations, while the TG secretion rate and other parameters were not influenced. Concerning all hormones effects on several lipid parameters have been observed. In particular, a decrease of FFA concentrations in comparison with controls after 16 h fasting was evident. In these cases, the TG secretion rate and TG concentration in serum were simultaneously lowered. Both alterations may be a consequence of a diminished mobilization of FFA in adipose tissue. Increases of FFA concentrations in serum after hormone application, compared with the corresponding controls, only occurred after administration of thyroxine and testosterone, while changes of the TG secretion rate and the TG concentration in serum were scarcely observed. Final remarks about the actual influence of hormones on the investigated parameters, especially TG secretion rate were drawn including results of a previous paper, where catecholamines, insulin, and prednisolone had been tested under the same conditions.

Adipose Tissue↗
PubMed1991

Hormonal effects on triacylglycerol secretion of rat liver.

The influence of epinephrine, norepinephrine, insulin, and prednisolone on the triacylglycerol (TG) secretion rate of rat liver was determined in vivo under different nutritional conditions (non-fasting, 10 and 16 h fasting, respectively). It was possible to estimate the triacylglycerol secretion rate by the Triton method without regard to fasting intervals. The subcutaneous administration of hormones was followed in all cases by changes of lipid parameters. Variations of secretion rate were found only by applications of norepinephrine, insulin, and prednisolone. Frequently, but not always, a change of free fatty acid (FFA) concentration in serum, that means a change of FFA mobilization in adipose tissue, was accompanied by an alteration of the TG secretion rate and in some cases by a change of TG concentration in serum in the same direction. We suggest that under these conditions the hormonal effect on TG secretion is realized by influence on the mobilization of FFA in adipose tissue. If the enhancement of FFA in serum is not followed by an increase of TG secretion, the elevated FFA influx into the liver is possibly used for oxidation or synthesis of phospholipids too. The role of nutritional factors was especially seen in 16 h fasting animals in which no rise of TG secretion rate was observed in spite of high FFA levels. In some cases reduced serum TG concentrations were observed without preceeding decreases of TG secretion rate out of the liver. Probably this effect is caused by increased clearance of serum TG.

Adipose Tissue↗
PubMed1990

[Phospholipid concentrations and localization of selected phospholipids in erythrocyte membranes of breast tumor patients].

The phospholipid content within the erythrocyte membrane, its composition and topological distribution was determined in 17 untreated patients with histologically verified breast cancer. The qualitative analysis of phospholipids was performed by one- and two-dimensional TLC. Topological changes of the aminophospholipid asymmetry were examined by TNBS-labelling. In comparison with control values, there were no significant differences of the investigated phospholipid parameters. In conclusion, in the early stage of breast cancer, there is no influence of tumour growth on the phospholipid pattern of red blood cells. Thus, diagnosis of breast cancer using erythrocyte phospholipids is impossible.

Breast Diseases↗
PubMed1990

[Age and sex dependence of phospholipid concentrations in human erythrocytes].

Phospholipid concentrations and composition of erythrocyte membrane were examined in 55 healthy volunteers (age: 20-62 years). All measured parameters were independent of age and sex of the individuals studied. Their reliability to be used as reference for further studies in patients was proved. The qualitative determination of phospholipids and their quantitative evaluation based on the chemical phosphate estimation was performed with TLC after extraction of the lipids from the intact erythrocyte.

Adult↗
PubMed1985

Some aspects of lipid metabolism in the liver of Wistar rats with fat diet-induced obesity.

Diet-induced obesity in rats can be produced by high-fat feeding. Comparing high-fat with low-fat feeding, the present study was designed to characterize the phases of development of obesity. In the dynamic phase, male rats were investigated at the age of 9-10 weeks after feeding the diets for 4-5 weeks. In the static phase, the animals at the age of 24-26 weeks were tested after 20-22 weeks of the nutritional regime. In this phase, the effects of switching high-fat to low-fat diet for 4 weeks were also examined. Fractionating lipid extracts by thin layer chromatography the concentrations of several lipids in epididymal adipose tissue, in serum, and in liver were determined. In liver, the enhancement of cholesteryl-ester (CE) concentration after high-fat feeding besides the accumulation of triglycerides (TG) is remarkable. Cell fractionation studies of the livers by differential ultracentrifugation showed the major part of the accumulated CE in the supernatant. In vitro incorporation of (1-14C)acetate and (2-14C)mevalonate into liver slices indicated that cholesterol synthesis in the liver of the obese rats was not increased. Although the offered fat diet with 0.1% of cholesterol can not be considered as high in cholesterol, the 2.5-fold higher amount of the high-fat diet in comparison with the low-fat diet (0.04% cholesterol) could be responsible for the enlargement of CE in the liver of the fat fed rats. This possibility was proved by measurement of the cholesterol absorption and transport to the liver after oral administration of (4-14C)cholesterol. Estimation of TG secretion rates of the liver using Triton WR 1339 pointed out higher rates in the obese rats in the dynamic phase. In the static phase, the rates were not different between both feeding groups, while fat restriction in the food produced a striking increase of TG secretion. It is assumed that only in the dynamic phase metabolism is able to compensate the liver TG accumulation by an enhanced transport to the adipose tissue. In the static phase this ability is diminished but not lost.

Adipose Tissue↗
PubMed1985

Fatty acid composition of liver and adipose tissue lipids in Wistar rats with fat diet-induced obesity.

The influence of dietary fat on the fatty acid composition of liver and adipose tissue lipids was investigated after 4 and 19 weeks of high-fat feeding (50% fat) in comparison to low-fat feeding (3% fat), beginning in the sixth week of age. In rats fed the low-fat diet or an usual pellet diet the fatty pattern of liver triglycerides (TG) was equal to that of adipose tissue, while there were no similarities to the diet. In total liver lipids a constant fatty acid profile was observed, independently of the duration of feeding. High fat feeding results several changes in the fatty acid pattern of liver lipids. While after 4 weeks the fatty acids of liver TG more closely resembled the dietary fatty acids than those of adipose tissue, after 19 weeks of feeding the fatty acid composition of liver TG is comparable with that of adipose tissue. Not all rats fed the high fat diet rendered obese. It could be shown that in rats with higher lipid concentrations in the liver only the fatty acid pattern of liver phospholipids has been altered, while the composition of TG, which are the lipids primarily increased, was not changed.

Adipose Tissue↗
PubMed1984

[Significance of serum uric acid determination for the early detection of complications of hypertensive pregnancy in primigravidae].

In 100 healthy primigravidae the concentration of serum uric acid was examined in a prospective longitudinal study between the 12th and 40th gestational week. Serum uric acid increased continuously and was elevated significantly in 9 women who developed toxaemia of late pregnancy at the 16th, 32nd, and 36th week of pregnancy. If serum concentration are higher than 220 mumol/l or 241 mumol/l in the 32nd gestational week they were considered for a increased risk of developing a hypertensive complication. Sensitivity, specificity and the predictive value of a "positive test" were low in the 16th (22 or 20%) and 32nd (16 or 17%) week of pregnancy. The predictive value of a "negative test" was relative high in the 16th and 32nd week with 93 or 90% respectively 95 or 92%.

Adolescent↗
PubMed1982

[Lipid concentrations in liver cell fractions in the rat in diet induced obesity].

The changes of lipid parameters induced in male Wistar rats by feeding a high-fat diet for several weeks were studied in cell fractions of the liver. For this purpose subcellular fractionations of liver tissue from 12-week-old animals receiving food containing, respectively, 3% fat (controls) and 50% fat, were performed by means of differential centrifugation, and the lipids in the cell fractions were determined quantitatively. The levels of triglycerides and cholesteryl esters both in total liver and in the cell fractions had risen several fold against the controls. Most of the accumulated lipids were retrieved in the cytosolic supernatant. In contrast, for the phospholipids and the free cholesterol only a slight increase in free cholesterol was observed in total liver, and increases of both lipids had occurred in the cytosolic supernatant, while the particulate fractions showed no alterations. It is pointed out in the discussion that the accumulation of triglycerides and cholesteryl esters in the liver largely concerns the particulate fractions too (observed so far in the literature only for single particulate fractions), which might be of interest for the function of the cell nucleus, the mitochondria and the endoplasmatic reticulum. The increase of phospholipids and free cholesterol in the supernatant has to be considered not only as a passive process of deposition, but could represent necessary contributions to the building up of lipid droplets in the cytosol during deposition of triglycerides and cholesterol in this region of the cell. The studies confirm that the fatty degeneration of the liver, true, is always the result of triglyceride accumulation but that, under certain conditions, cholesterol is also enriched in the form of its esters.

Animals↗
PubMed1980

[Triglyceride secretion of the rat liver under various conditions of fool-induced obesity].

The secretion rates of triglycerides from liver into plasma of obese animals and controls, as well as in obese animals 4 weeks from feeding a fat-deprived diet were determined. In the dynamic phase of obesity (9-week-old animals receiving fat-rich food for 4 weeks) an increase in secretion rate over the control was determined, which persisted to the same extent after having fed a fat-deprived diet for 4 weeks. In the static phase of obesity (24-week-old animals given a fat-rich diet for 9 weeks) the control animals showed the same secretion rate as the control animals in the dynamic phase. In contrast to the dynamic phase, obese animals revealed no changes of the secretion rate also in these animals. Since the present knowledge about the regulation of triglyceride release from the liver into the plasma via the VLDL is scarce, various food-, hormone-, and enzyme effects have been discussed in more detail, and the changes observed were correlated, on the basis of own experiments, in particular with hyperinsulinemia present in the obese animals and with the increased supply of free fatty acids to the liver in the dynamic phase of obesity. The changes in secretion rate following the shift to fat-deprived food cannot at present be satisfactorily explained.

Animals↗
PubMed1978

Plasma concentrations of insulin and free fatty acids in dietary-induced obesity of Wistar-rats before and after glucose stimulation.

Colony-bred Wistar-rats develop obesity after long term feeding with a high-fat diet (50% fat, w/w). According to previous investigations a disturbed glucose tolerance after i.v. glucose load could be described for obese rats. Therefore, we measured peripheral IRI-concentrations before and after glucose stimulation in controls and fat-fed rats. In obese animals we observed a basal hyperinsulinemia in the dynamic phase of development of obesity. In controls and fatty rats, no differences in the peripheral insulin response to an i.v. glucose stimulation could be demonstrated, nor did we find indications of an impaired early insulin response in fatty rats. In accordance with the glucose tolerance study, obese rats in the dynamic phase showed lower FFA-levels (fasting state) and a slower decrease of FFA-concentrations after the glucose-induced insulin enhancement. Changing the feeding schedule at 20 weeks of age, e.g. feeding control diets to fatty rats for 4 weeks, reduced basal IRI-concentrations in these animals to control values. Assuming the secondary nature of the basal hyperinsulinemia in obese rats, our present results demonstrate that the observed impairment of glucose tolerance may be related to the peripheral insulin resistance of skeletal muscle and/or hypertrophied adipose tissue.

Animals↗
PubMed1978

[Changes in lipid metabolism of Wistar rats by changing a high fat to a low fat diet and vice versa].

Wistar rats, 24 weeks of age, with alimentary obesity after fat feeding (50% fat in the diet) for 19 weeks were restricted to fat (3% fat in the diet) for 4 weeks in order to compare the alterations of body and organ weights as well as those of lipid concentrations in epididymal adipose tissue, liver and serum with earlier results [1], obtained before food changing. On these conditions decreases of body weight by about 20%, of the relative mass of epididymal adipose tissue and of the triglyceride content per fat cell were observed. In liver a decline of triglycerides and cholesterylesters (by about 2/3 and 1/3, respectively) and in serum a drop of free fatty acids, but increases of phospholipids, and of free and esterified cholesterol were found. In another series, animals of the same age that had been fed the low fat diet for 19 weeks were administered the high fat diet for 4 weeks and also compared with the state before. Thereby the body weight (by about 20%) and the relative mass of the epididymal adipose tissue gained, but lipid concentrations in this tissue were not affected. In liver the concentrations of triglycerides and cholesteryl esters increased threefold and tenfold, respectively; in serum augmented contents of triglycerides and phospholipids were observed. Besides the changes in adipose tissue, reasons for the forced accumulation of cholesteryl esters in the liver during fat feeding and their retarded removal out of the liver after fat restriction are especially discussed in comparison with that of the triglycerides.

Adipose Tissue↗
PubMed1977

[Kidney changes in experimental obesity].

In a survey renal changes in human obesity as well as in experimental obesity of laboratory animals are discussed. Own results are described about a comparison of biochemical and morphological studies on an experimental model of dietary-induced obesity after long-time feeding of a high-fat diet. Obese rats show normal concentrations of plasma proteins after feeding of a high-fat diet of some weeks. Urea-nitrogen levels are not modified as compared to control animals. Despite the mean levels of creatinine concentration in the dynamic and static phase of obesity are not different, some obese rats show increased creatinine values in the dynamic phase. Our histological studies reveal no pathological abnormalities of renal structures and blood vessels.

Animals↗
PubMed1977

Basal hyperinsulinemia in Wistar-rats rendered obese by a high-fat diet.

Basal plasma insulin levels were measured in Wistar-rats rendered obese by feeding a high-fat diet (50% fat, w/w). During the period of rapid weight-gaining ("dynamic phase" of the development of obesity) fat-fed rats show elevated basal insulin levels in the peripheral blood plasma. No further enhancement occurred in the so-called "static phase" of obesity. Changing the feeding schedule at 20 weeks of age, e.g. feeding control diets (3% fat, w/v) for 4 weeks to fatty rats, results in a depression of insulin levels to control values together with a reduction of the body weight. The findings are discussed in relation to the dietary induced alterations of carbohydrate and lipid metabolism of obese rats.

Animals↗
PubMed1976

[Biochemical parameters of blood plasma, and body and organ weights of Wistar rats with dietarily-induced experimental obesity].

The authors investigated in rats with dietarily-induced obesity certain biochemical parameters of the blood plasma as well as body and organ weights during the dynamic and the static phase of obesity development. They determined total cholesterol, total protein, albumin, creatinine, urea nitrogen and transaminases. After 4-5 weeks, the animals on a high-diet (50% of fat) had body weights which were, on an average, by 90% higher than those of the control animals. This difference persisted during the static phase. In the animals on a high-fat diet, body length was greater. The high-fat diet (which contains a great proportion of sunflower oil) leads to a decrease of the plasma cholesterol level in obese rats. The plasma-protein bodies, creatinine and urea nitrogen values as well as those for transaminases permit, as parameters for function and damage, to draw conclusions as to kidney and liver damages in the animals on high-fat diet. There were no differences in plasma protein between the control and experimental animals. On the contrary, obese rats showed in some cases high creatinine concentrations during the dynamic phase. Differences in urea nitrogen were not observed between the two groups of animals. Increases in alanine aminotransferase were found in the animals on high-fat diet as a manifestation of fatty degeneration of the liver. A synopsis of weight curves, biochemical parameters and histological findings permits the conclusion that, besides of dietarily-induced metabolic alterations, no additional organic lesions occurred during the present animal experiment on dietarily-induced obesity.

Alanine Transaminase↗