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D Sasse

Publications and source records attributed to D Sasse.

At least 73 records · Page 4Linked to original sources
PubMed1976

[The fructose induced "glycogenosis". II. Histochemical studies of glycogen metabolism in rat liver after fructose overload and similar diets (author's transl)].

INTRODUCTION: Feeding of fructose for 7 days has been morphometrically shown to induce a SER-reduction and an accumulation of glycogen in rat liver cells. This hypothetical model "glycogenosis" is investigated with histochemical methods. MATERIAL AND METHODS: Rats are given a solution of 60% fructose in water as only nutritional source. Controls are given a solution of 60% glucose in water, an isocaloric Altromin-R-standard diet and an Altromin-R-standard diet ad libitum. Reversion of fructose induced metabolic changes is investigated by a 7 days fructose diet followed by an 1-4 days Altromin-R-standard diet ad libitum. Glycogen and glycogen metabolizing enzymes are demonstrated after a 7 days diet and in the course of an 1-7 days fructose diet. RESULTS AND DISCUSSION: Feeding of fructose leads to a high glycogen content, combined with a high activity of glycogen-phosphorylase and glucose-6-phosphatase in the liver parenchyma. Glycogen-synthetase activity increases during the first 4 days and then it drops to a low level. A pathological alteration of liver cell metabolism seems to be improbable, for all fructose induced changes are reversibel after 2 days of Altromin-R-standard diet. Glucose-6-phosphatase, as a marker-enzyme of the smooth endoplasmatic reticulum, is discussed to become activated by disruption of SER membranes due to fructose.

Acid Phosphatase↗
PubMed1975

Dynamics of liver glycogen: the topochemistry of glycogen synthesis, glycogen content and glycogenolysis under the experimental conditions of glycogen accumulation and depletion.

Using histochemical techniques the glycogen content and the activities of glycogen synthetase (UDPGGT) and phosphorylase were studied in the livers of 106 golden hamsters under following experimental conditions; a) starvation of 16, 36, 48, 72, and 96 hours: b) alloxan-diabetes. Starvation leads to a depletion of liver glycogen during the first 48 hours, which is finally restricted to zone 3 of the liver acinus. After starvation of 72 and 96 hours a new glycogen accumulation is demonstrable in the microvasculatory periphery of the acinus (zone 3 and 2). The process of glycogen depletion is characterized in the beginning by a high phosphorylase activity in all zones of the acinus, later only in the forefield of glycogen content. The weak activity of glycogen synthetase is mainly restricted to zone 3. All phases of glycogen depletion are to be found in alloxan diabetic animals, too. Out of 45 hamsters 23 showed an extreme depletion of glycogen; typical for this situation is a weak or absent glycogen synthetase activity in zone 3 and a broad field of phosphorylase activity in zones 1 and 2. The short stimulation by insulin leads to a considerable increase of glycogen synthetase activity at the portally oriented border of the glycogen area and to a shift of the moderate phosphorylase activity of zone 1. Thus the histochemical characteristics of glycogen depletion are: a shift of the reduced glycogen content in direction of the microvasculatory periphery of the liver acinus (zone 3), caused by a high phosphorylase activity in the portal forefield, while glycogen synthetase activity is low in the glycogen area. The histochemical characteristics of glycogen accumulation are: after a short phase of glycogen synthesis in all hepatocytes a moderate phosphorylase activity in zone 1 leads to a mobilization of the portal glycogen deposits and to an increasing accumulation of glycogen in the peripheral part of the acinus. At the portally oriented border of the glycogen area a high synthetase activity leads to a broadening of the glycogen area in direction of the portal branches. At the end of this process the "normal" pattern of the liver acinus occurs: all hepatocytes are filled with glycogen, the glycogen enzymes are restricted to the periportal border of zone 1.

Animals↗
PubMed1975

[The fructose induced "glycogenosis". I. Ultrastructural and morphometric analysis of rat hepatocytes 7 days after fructose overload (author's transl)].

INTRODUCTION: Infusion of fructose has been shown to stimulate the SER and to reduce the RER in rat liver cells. After feeding fructose of 7 days a glycogenosis of unknown pathogenesis occurs, which was analysed morphometrically. MATERIAL AND METHODS: 60% fructose in water, was given as drinking water to animals deprived of other food. Controls had free access to Altromin-R-standard diet and drinking water. Liver tissue was analysed morphometrically according to the methods described by Weibel. RESULTS AND DISCUSSION: Rat hepatocytes accumulate a material with histochemical properties of glycogen. The enlargement of hepatic nuclei is probably due to a pathological edema. The SER is decreased suggesting a drop of glycogen catabolizing enzymes. The drastic reduction of the RER and the non-membrane bound ribosomes are signs of inpeeded protein synthesis. According to this, the peroxisomes, which arise from the RER, are decreased in volume and number. The hepatocellular chondrioma is transformed morphometrically in a smaller number of larger, pleomorphic and cup-shaped mitochondria. The ATP level drops while, on the other hand, the cristeal membranes increase. This might be caused by a negative feed back mechanism. The hepatocellular cytoarchitecture described is similar to the one found in glycogenosis type I and in the cerebrohepato-renal syndrom.

Animals↗
PubMed1975

[A 3-dimensional presentation of the functional liver unit].

The reconstruction of the liver parenchyma of a golden hamster after poisoning with allyl formate is described. Allyl formate primarily destroys the periportal areas and leads, following the microvascularisation of the liver parenchyma, to a necrosis of the hepatocytes progressing towards the terminal hepatic venule. The still intact parenchymal zones can be characterized by the positive PAS reaction. In this study the preterminal and the terminal portal branches as well as zone 3, situated in the vasculatory periphery, were reconstructed. By this method, a three-dimensional presentation of the acinar functional zones was possible for the first time.

Allyl Compounds↗