Heinz David

Vergleichende histochemische, fluorescenzmikroskopische und elektronenoptische Untersuchungen zur Frühdiagnose des Herzinfarktes der Ratte

In vergleichenden histochemischen, fluorescenzmikroskopischen und elektronenoptischen Untersuchungen am experimentellen Herzinfarkt der Ratte wurden folgende Befunde erhoben: Entsprechend den Angaben der Literatur warenelektronenmikroskopisch die frühesten Veränderungen schon nach. 15 min zu erfassen (Faserödem, vacuolige Umwandlung des Sarkoplasmareticulums und beginnender Zerfall der Struktur einzelner Mitochondrien).Histochemisch kommt es in Übereinstimmung mit den Angaben der Literatur zu einer von der Zeit-dauer des Infarktes abhängigen Aktivitätsminderung der Succinodehydrogenase und alkalischen Phosphatase, dagegen zeigt die Cytochromoxydase eine Zunahme der Aktivität. BeiFluorochromierung mit Acridinorange und Coriphosphin zeichnet sich der Infarkt durch einen schon nach 3 Std sicher erfaßbaren Farbumschlag aus. Außerdem finden sich Veränderungen der Kernfluorescenz. Beim experimentellen Herzinfarkt gelingt es also, auch mit Hilfe der Fluorescenzmikroskopie morphologische Veränderungen früher als mit lichtmikroskopischen Methoden zu erfassen. Das besondere Verhalten der subendokardialen Muskelschichten ergibt sich daraus, daß dieses Gebiet neben der capillären Gefäßversorgung zusätzlich durch Diffusion vom Herzlumen her ernährt wird. Comparative histochemical, fluorescence microscopic, and electron microscopic studies of experimental infarcts of the hearts of rats revealed the following: In agreement with statements in the literature, the earliest changes were detectable electron microscopically after 15 minutes (edema of the fibers, vacuolar change in the reticulum of the sarcoplasm, and a beginning degeneration in the structure of individual mitochondria). Histochemically, in agreement with reports in the literature, the activity of the succinic dehydrogenase and alkaline phosphatase decreased, depending on the duration of the infarct. In contrast, the activity of the cytochrome oxidase increased. With fluorochromation with acridine orange and coriphosphine the infarct was characterized by a color change detectable after three hours. In addition, changes in the fluorescence of the nuclei were evident. With experimental cardiac infarcts it was possible, therefore, to detect morphologic changes with the fluorescent microscope earlier than with the light microscope. It may be assumed from the special behavior of the subendocardial muscle, that the tissues here receive their nourishment not only by way of the capillaries but also by diffusion from the cardiac chamber.

Morphometric characterization of left ventricular myocardial cells of male rats during postnatal development

Abstract Morphometric investigations of the left ventricular myocardial cells of male Wistar rats aged 0, 1, 2, 3, 4, 5, 6, 7, 14, 21 days and 1, 2, 3, 4, 5, 6 months were carried out. The volume density of the sarcoplasm decreased from 0.33 (at birth) to 0.018 (6th month). The volume density of the myofibrils diminished during the first 7 days of life, whereas after the 6th month (0.57) it was nearly the same again as at birth (0.52). The volume density of the mitochondria increased from 0.16 at birth to 0.33 in the 6th month. The surface density of the outer mitochondrial membrane increased at different rates. The number of mitochondria per unit area grew from 0.51 (at birth) to 0.88 (6th month). The distance between the mitochondria decreased from 4.33 μm (at birth) to 1.67 μm (6th month). The mitochondrial/myofibrillar ratio doubled in the course of the period covered by the study (0.32 at birth; 0.64 in the 6th month). The postnatal development of heart muscle cells can be characterized by data obtained on the heart at birth, at the ages of 3, 4, 5, 7, and 14 days and in the 1st, 3rd and 6th month.

Correlated ultrastructural and morphometric studies on the liver during prenatal development of rats.

Quantitative and qualitative changes in liver tissues during prenatal development were studied by electron microscopy and morphometry. On the 15th day, 30% of fetal liver volume consisted of hepatocytes, and the extrahepatocytic spaces amounted to 63%. The hemopoietic cells occupied 93% of the extrahepatocytic spaces. Immature bile canaliculi were observed and amounted only to 0.14% of extrahepatocytic spaces. The hepatocytes were irregular in shape and possessed several large lipid droplets which amounted to 19% of the cytoplasm. Although the rough surfaced endoplasmic reticulum (RER) was well developed, the smooth surfaced endoplasmic reticulum (SER) was not yet differentiated. The typical peroxisomes with nucleoid and glycogen were not observed in the cytoplasm. On the 18th day the volumetric densities of hepatocytes and bile canaliculi were increased. The typical peroxisomes with nucleoid appeared in the cytoplasm. The accumulation of glycogen which amounted to 12% of the cytoplasmic volume had taken place, while the volume of lipid droplets decreased significantly. In glycogen areas the differentiation of SER began. At birth the histogenesis of the liver was well established. The hemopoietic cells decreased in number and were confined to perisinusoidal spaces. The volumes of biliary capillaries and sinusoids were comparable with these of young rats now. The volumetric density of hepatocytes increased and occupied about 74% of the liver. The volumetric densities of mitochondria, SER, peroxisomes, secondary lysosomes, and lipid droplets increased significantly in comparison with those of the 18 days old fetus, while RER, Golgi area, and primary lysosomes were rather constant. The volumetric density of glycogen decreased rapidly at birth.

Zur Morphologie der Leberzellmembran

ZusammenfassungDie Leberzellmembran und ihre Bildungen wurden im Bereich der Sinusoide, der Gallenkapillarwand und der aneinandergrenzenden Parenchymzellen bei Mäusen, Ratten, Meerschweinchen, Goldhamstern, Kaninchen, Tauben und Gold-fischen vergleichend untersucht. Im Gebiet des Disséschen Raumes sind keine sicheren Unterschiede zu finden. Dagegen liegen im Bereich der Gallenkapillaren und der aneinandergrenzenden Parenchymzellen viele charakteristische Struktur-elemente vor, so daß bei der Untersuchung dieser Membranteile eine Zuordnung der Leber zu einer bestimmten Tierart im allgemeinen möglich ist.

Quantitative ultrastructure of the rat liver by immersion and perfusion fixations

Morphometric and qualitative investigations of rat liver with immersion fixation (I) and perfusion fixation (P) have not produced any statistically significant differences in the volume densities and numbers per area of elements of hepatocytes: Vv mitochondria: 0.194 (I), 0.189 (P); peroxisomes 0.011 (I), 0.012 (P); glycogen 0.196 (I), 0.183 (P); agranular endoplasmic reticulum 0.144 (I), 0.183 (P); granular endoplasmic reticulum and groundplasm 0.455 (I), 0.437 (P). The numbers per unit area (micrometers 2) for the mitochondria are 0.492 (I) and 0.496 (P), and for the peroxisomes 0.048 (I) and 0.044 (P), respectively. From the results, the following conclusions can be drawn: -- There are no differences in qualitative and quantitative findings as to the preservation of the hepatocytes by immersion and perfusion fixation. Immersion fixation can be applied as analogous and equivalent methods in routine investigations of human excision and bioptic tissues and also of very large and very small organs. -- Ischemic autolytic alterations of the cells, especially in the mitochondria occur: with immersion fixation in the surface zone and the central zone of the specimen (the intermediate zone is well preserved), with perfusion fixation in different areas. -- Alterations in the sinusoidal wall affect the width of the lumen and the openings of the endothelial cells which show better conditions at optimum pressure and flow rate of the perfusion fluid. -- Pronounced alterations in the endothelial cells, partially the total destruction and detachment are caused by non-optimal pressure and flow rates of the perfusion. They may appear, however, as secondary results caused by the composition of the fluid or circumscribed constrictions of the vascular system of the liver. -- With regard to the transplantology of the liver the studies on the perfusion fixation demonstrate the importance of pressure, flow rate and composition of the perfusion fluid for preserving the tissue, especially the sinusoidal wall.

On the mechanism of cell desquamation of the small intestine villi. (Electron microscopic studies)

Unter Normalbedingungen erfolgt die Abstoßung nach Degeneration der Zellbestandteile und Schrumpfung der Zelle mit Ausbildung einer Pyknose, ohne daß die geschlossene Epithelbedeckung eröffnet wird. Die benachbarten Epithelzellen pressen nämlich die Zellen von unten her aus dem Verband und schließen die entstehenden Lücken noch vor der endgültigen Abstoßung. Unter pathologischen Bedingungen lösen sich die Zellen aus dem Verband bei gleichzeitiger Zerstörung des Schlußleistenkomplexes. Damit entstehen Lücken in der Epitheldecke, durch die unkontrolliert Substanzen, Bakterien und Partikel verschiedenster Größe ins Zottenstroma und damit in die Blutbahn übertreten können. Da normalerweise keine Eröffnung der Epithelbedeckung vorhanden ist, müssen die von anderen Autoren beobachteten großen Partikel entweder durch Phagocytose der Epithelzellen oder durch Hineinpressen in Becherzellen in das Zottenstroma und damit in die Capülaren gelangen. Under normal conditions the desquamation takes place after the components of the cell degenerate and the whole cell shrinks with the development of pyknosis without the continuity of the epithelial covering being broken. The adjacent epithelial cells press the degenerating cells out of the complex from below and close the breaks before the definitive exfoliation. Under pathologic conditions the cells are freed from the epithelial covering with simultaneous desintegration of the junctional complexes. In this manner breaks arise in the epithelial covering through which substances, bacteria and particles of various size, may penetrate into the villous stroma and capillaries. Since no break of the epithelial covering normally exists, the large particles observed by other authors must get into the villous stroma and hence into the capillaries by phagocytosis by the epithelial cells or by being pressed into the goblet cells.

Quantitative and qualitative changes in the mitochondria in hepatocytes during postnatal development of male rats.

The volume density of mitochondria increases during postnatal development of the hepatocytes of male rats (test ages: 0 [birth], 1st, 2nd, 3rd, 4th, 5th, 6th, 7th, 14th, 21st, 28th day and 2nd, 3rd, 4th, 5th and 6th month) from 0.165 at birth to 0.236 on the 14th day, after which it decreases to 0.139 until the 6th month. At the same time the absolute volume of the mitochondria of the hepatocytes increases from 728.8 micrometer 3 at birth to 1225.5 micrometer 3 on the 14th day and reaches a maximum of 2102.3 micrometer 3 at the end of the 2nd month. The number of mitochondria per hepatocyte is 204 at birth. It increases continuously and reaches 2199 at the end of the 6th month. The volume of the average mitochondrion on the other hand diminishes during postnatal development from 3.83 micrometer 3 at birth to 0.64 micrometer 3 towards the end of the 6th month. Transverse divisions of mitochondria, budding of parts of mitochondria, autophagocytotic processes and degenerative changes can be observed throughout this period.

Zur Mitochondrienneubildung in den Leberzellen des Feuersalamanders (Salamandra maculata)

ZusammenfassungIn den Leberparenchymzellen des Feuersalamanders ist eine besondere Form der Neubildung von Mitochondrien zu beobachten. Es kommt zur intramito-chondrialen Entstehung junger Mitochondrien, die durch einen als „Geburt“ bezeichneten Mechanismus aus dem Muttermitochondrion ausgestoßen werden.

Alteration of the ultrastructure of the pig liver after a continuous perfusion of six hours in vitro

Livers of mini LEWE pigs were perfused continuously for 6 h on a novel perfusion system through the portal vein (laminar flow from 200 to 300 ml/min, pressure 270 Pa) and through the A. hepatica (pulsating flow from 100 to 200 ml/min, pressure: 10.6/5.5 kPa). The following perfusion media were used for determining the best conservation conditions at 10 to 12 degrees C: Pig blood/Krebs-Henseleit bicarbonate buffer 1:1; Pig blood/Ringer lactate solution 1:1; Pig plasma; Collins C 2 perfusion solution. After perfusion with Collins C 2 solution the hepatocytes show swelling and dilation of the granular endoplasmic reticulum; after perfusion with the other solutions the changes of the hepatocytes are negligible. The alterations of the sinusoidal wall cells depend on the perfusion pressure and flow and the composition of the solution. After continuous perfusion the sinusoidal walls are characterized by vesicles of endothelial cells, dilatation of the Disse space and fragmentation of hepatic microvilli.

Morphometric analysis of peroxisomes in the liver cells of male rats during postnatal development.

Summary Quantitative changes in the cell components of male Wistar rats (Rehbrucke stock) were determined daily from birth to the 7th day, on the 14th, 21st and 28th day and monthly from the 2nd to the 6th month. At birth, peroxisomes have a volume density of 0.021 ± 0.001, which does not change substantially until the 6th month (0.022 ± 0.008). Numerical density increases from 0.0277 ± 0.0014 at birth to 0.0863 ± 0.0033 in the 6th month. The relative volume of peroxisomes increases in the same period from 98.9 ± 5.2 μm 3 to 221.4 ± 8.3 μm 3 . The number of peroxisomes per hepatocyte increases from 130.4 ± 6.8 to 868.5 ± 33.4. The volume of the individual peroxisome, on the other hand drops from 0.79 μm 3 to 0.25 μm 3 . Changes in peroxisomes vary in the sinusoidal zone, the lateral zone and the zone near the bile canaliculi.