Morphometrische Untersuchungen an Zellen

Sitte, Hellmuth

doi:10.1007/978-3-642-50130-2_10

Cited by 33 publications

(23 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A square grid of sampling lines (the distance of the lines normally being 10 mm, for the sampling of lysosomes 5 mm) was projected on electron micrographs with a final magnification of 20,000 x . The sampling lines were projected under an angle of 19° (or 71°) with respect to the basis of the cells, as suggested by Sitte (1967) for the analysis ol non-randomly distributed cellular structures. Only circular cross sections of the tubular epithelia were used for ultrastructural analysis.…”

Section: Methodsmentioning

confidence: 99%

The effect of prolactin on kidney structure of the euryhaline teleost Gasterosteus aculeatus during adaptation to fresh water

Bonga

1976

Cell Tissue Res.

View full text Add to dashboard Cite

Summary.The effect of injections of ovine prolactin on kidney structure was examined in the first 10 days following transfer of seawater sticklebacks to fresh water.In hormone injected animals as well as in controls the glomeruli increase slightly in size after transfer. The podocytes intensify the secretion of m ucopo lysaccharides, which is indicative of increased turnover of the components of the glomerular basal lamina. The nuclei of the podocytes become enlarged, while those of the juxtaglomerular cells decrease in size. These changes are related to the well known rise of the glomerular filtration rate following transfer to fresh water. Structural indications that prolactin is involved in the control of glomerular filtration were not found.The epithelial cells of the three nephronic segments and of the ureter become considerably better developed after transfer to fresh water. Cell height, nuclear and mitochondrial volume, and surface of the membranes of the basal labyrinth increase in all tubular epithelia, although not to the same extent. Increases are moderate in the first proximal segment, but in creasingly higher for the second proximal segment, collecting duct and the ureter. Especially the growth of membrane surface of the basal labyrinth, site of ion transport mechanisms, is impressive. In controls, values character istic for freshwater fishes are reached in 6 to 9 days for all parameters for cellular development. Prolactin injections greatly stimulate growth rates in all tubular epithelia: freshwater values are reached within 3 days. No further increase was found, however.

show abstract

Section: Methodsmentioning

confidence: 99%

The effect of prolactin on kidney structure of the euryhaline teleost Gasterosteus aculeatus during adaptation to fresh water

Bonga

1976

Cell Tissue Res.

View full text Add to dashboard Cite

show abstract

“…The percent volume fractions of various subcellular components were measured by the stereological technique of point counting (Weibel et al, 1966;Weibel and Elias, 1967;Sitte, 1967;Underwood, 1970;Elias et al, 1971). A transparent sheet (20.3 cm x 25.4 cm) with a square grid (1 cm/side) photographically imprinted on it was used for mea- VOL.…”

Section: Stereological Techniquementioning

confidence: 99%

Myocardial morphometric characteristics in swine.

Singh¹,

White²,

Bloor³

1981

Circulation Research

View full text Add to dashboard Cite

SUMMARYWe have quantified the ultrastructure of myocardial cells in tissue samples obtained from six adult normal Yucatan swine, tissue samples were obtained from 20 different sites in the left ventricle, right ventricle, and interventricular septum. The samples were processed for electron microscopy and quantitative morphometric analysis. The percent relative volumes of myoflbrils, mitochondria, transverse tubular system, sarcoplasmic reticulum, and clear intracellular space were determined using stereologic&l morphometric methods. Overall, the data were distributed homogenously among the 20 individual sites. However, when certain eubcellular components were examined regionally, some differences appeared. The mitochondrial:myofibril volume ratios were significantly increased in the left ventricle and interventricular septum compared to the right ventricle. They also were greater in the endocardial region compared to the epicardium, which is consistent with higher metabolic activity of these zones. Similarly, the sarcoplasmic reticulum :myofibril ratio was greater in the endocardial region vs. the epicardial region and the basal layer compared to the mid-layer, suggesting the greater need for provision of calcium ions in these particular cones. Since the swine is a convenient large animal fur physiological studies, these results indicate that swine can also be used for quantitative morphometric measurements of myocardial changes in normal and pathologic hearts, and for the study of regional changes in various layers and regions of heart walls. Circ Res 49: 434-441, 1981 MANY experimental models of cardiac hypertrophy have been used to describe the different functional, structural, and biochemical alterations that occur during the development of hypertrophy and failure in the heart. We nave used swine as a model of cardiac hypertrophy (White et al., 1979) since its response to exercise stress is similar to that in humans. Also, the swine has a coronary artery distribution similar to that of the normal human (Lumb and Hardy, 1963), a limited coronary collateral circulation (Blumgart et al., 1950), and a similar ratio of heart weight to body weight to that of man (Schaper, 1971). Therefore it is an appropriate model for comparison to man (Blumgart et al., 1950; Lumb andSingletary, 1961;1962;Lumb and Hardy, 1963;Kong et al., 1969). However quantitative ultrastructural studies of the normal and hypertrophic heart have been conducted mainly in smaller species, e.g., rats (Page et al., 1971;Anversa et al., 1976Anversa et al., , 1978Legato, 1976; Wendt-Gallitelli and Jacob, 1977;McCallister et al., 1979;Tomanek et al., 1979), rabbits (Anversa et al., 1971;Goldstein et al., 1974), hamsters (Colgan et al., 1978), cats (Sheridan et al., 1977), and ferrets (Breisch et aL, 1980). Although ultrastructural studies have been conducted on the hearts of dogs (Vitali-Mazza and Anversa, 1972;Winkler et al., 1977;McCallister et al., 1978;Legato, 1979), it was not known whether the percentages of cell volume of ultrastructural ...

show abstract

“…13 Both longitudinal and transverse sections of muscle cells were used for point countings and the data were averaged.…”

Section: Quantitative Assessment Of Volume Fractions Of Myofibrils Anmentioning

confidence: 99%

Canine atrial and ventricular muscle mechanics studied as a function of age.

Urthaler¹,

Walker²,

Kawamura³

et al. 1978

Circulation Research

View full text Add to dashboard Cite

SUMMARY Age-dependent differences in mechanical performance and morphometric and electron microscopic characteristics of atrial and ventricular trabeculae are described. At 3 months, atrial and ventricular trabeculae develop the same amount of force. At 9 months, the ventricular muscle develops twice as much force as its atrial counterpart, although shortening is almost identical in both muscles. At any age, velocity of shortening of atrial trabeculae is at least twice that of the ventricular muscles. StereologicaJ data indicate that atrial and ventricular working myocytes maintain fixed volume fractions of myofibrils (70%) and mitochondria (25%) between 3 and 9 months of age. A broad frequency distribution of sarcomere lengths was measured at Lmax in muscles of the younger age groups. More than 80% of sarcomeres of adult atrial and ventricular myocytes clustered around 2.05 to 2.25 /im; only 30% of sarcomeres of younger atrial myocytes and 45% of sarcomeres of younger ventricular myocytes were within that length bracket. About 45% of sarcomeres in younger atrial muscles had lengths in excess of 2.35 pm; less than 3% of sarcomeres were longer than 2.35 fun in adult atrial muscles. Sarcomere lengths cluster more and more around the mean with increasing age, suggesting that with maturation there is a more homogeneous recruitment of sarcomeres. At both ages, there is a marked difference between atrial and ventricular myocytes whether examined in terms of morphological development or functional performance. We conclude that any work correlating myocardial structure and function must account for two things: the site from which the muscle was excised and the age of the donor heart. AGE-RELATED changes in developed tension, 1 passive elastic stiffness, 2 or maximum velocity of shortening' 1 are as well established as age-related differences in the sensitivity to digitalis. 4 It also is well known that the heart is not made of a homogeneous population of working myocytes and that the differences in structure 5 '" and function 7 -a between atria and ventricles are quite marked. Age-related changes in ventricular contractility have been studied in some detail in lambs and sheep 1 and in cats, 9 " 11 but little or no attention has been given to the effects of maturation on atrial contractile performance in any species. 1 -9 In this study we describe age-dependent differences in the mechanical performance of isolated canine atrial and ventricular trabeculae. Presentation of the physiological observations is combined with morphometric and electron microscopic data from atrial and ventricular trabeculae previously studied in the myograph. MethodsThirty-six mongrel dogs of either sex were anesthetized with sodium pentobarbital, 30 mg/kg, iv. Two age groups were studied: one group was (n = 18) 13 ± 4 weeks old (3 months) and the second group (n = 18) 35 ± 5 weeks old (9 months). The entire heart was rapidly removed and placed in a beaker of Krebs-Ringer's bicarbonate solution that was gassed at 37°C with a 95% O 2 -5% CO 2 g...

show abstract

Morphometrische Untersuchungen an Zellen

Cited by 33 publications

References 20 publications

The effect of prolactin on kidney structure of the euryhaline teleost Gasterosteus aculeatus during adaptation to fresh water

The effect of prolactin on kidney structure of the euryhaline teleost Gasterosteus aculeatus during adaptation to fresh water

Myocardial morphometric characteristics in swine.

Canine atrial and ventricular muscle mechanics studied as a function of age.

Contact Info

Product

Resources

About