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PubMed1991

Comparative morphometry of Bergmann glial (Golgi epithelial) cells. A Golgi study.

Bergmann glial (Golgi epithelial) cells were Golgi-impregnated in the cerebella of species with great differences in the thickness of the molecular layer, in small African native mouse, rat, rhesus monkey, and man. The thickness of the molecular layer determines the length of the radial Bergmann cell processes. Whereas the overall morphology of the cells was found to be strikingly similar in all species studied, there were great quantitative differences in length and diameter of the stem processes. Species with thick molecular layers (man, monkey) have thicker stem processes than species with short distances between Bergmann glial cell soma and pial surface (rat, mouse). This could mean that larger animals with longer gestation periods allow for prolonged growth of cell volumes. On the other hand, an increase in the diameter of long processes should reduce the cytoplasmic resistance against ionic currents; this would be important when Bergmann glial cells--like retinal Müller cells--would act as "cables" for spatial buffering of potassium ions released by electrically active neurons. By contrast, the fractal dimension--i.e., a quantitative measure of the complexity of the cell's border--of the cell processes was lower in species with long processes. In an age series of rat cells, the fractal dimension is shown to increase slightly up to a very old age.

Animals↗

PubMed1993

An analysis of HRP-filled basket cell axons in the cat's cerebellum. I. Morphometry and configuration.

Basket cell axons terminate directly on the Purkinje cell body in the mammalian cerebellum and thus are in a position to have a direct influence on this neuron. In the present study, individual basket cells were intracellularly filled with horseradish peroxidase and the morphological characteristics and distribution of their axons were analyzed and quantified. The horizontally directed axon of basket cells preferentially distributes toward one side of the cell body, and is usually directed toward the base of the folium. In their course, the axons give rise to three types of axonal specializations including descending collaterals that form the complex endings around the axon hillocks and somata of Purkinje cells (i.e. the pinceau), beaded tendrils that arise from the descending collaterals and distribute to the Purkinje cell and upper granule cell layer, and beaded tendrils that arise directly from the horizontal axon to enter the molecular layer. In some respects, basket cells comprise a heterogeneous population of neurons on the basis of the length of their axon, as well as the number, distribution, and morphological characteristics of the axonal collaterals. The major finding of this study is that a single basket cell does not form a pinceau around the axon hillock of every Purkinje cell located along the course of its horizontal axon. Further, the pinceaux that are formed vary in their complexity. These findings suggest that the classic concept of off-beam inhibition mediated by basket cells is more complex than previously described.

Animals↗

PubMedDate not supplied

Ultrasound biomicroscopic morphometry of the anterior eye segment before and after one drop of pilocarpine.

PURPOSE: To measure anterior eye-segment morphometric data using ultrasound biomicroscopy. This is a new high-frequency, high-resolution ultrasound method enabling the visualisation of the anterior segment of the living eye with magnification similar to a light microscope. METHODS: Thirteen morphometric parameters of the anterior eye segment were measured before and after the application of one drop of pilocarpine in 10 eyes of 5 persons, using a Zeiss-Humphrey Ultrasound Biomicroscope at a frequency of 50 MHz. In each session, 3 morphometric parameters in the central images (corneal thickness, anterior chamber depth, pupillary diameter) were measured 4 times, and 10 parameters in the radial images (scleral thickness, angle-opening distance, trabecular-iris angle, trabecular-ciliary process distance [TCPD], iris thickness, 1, 2 and 3, iris-ciliary process distance, iris-lens contact distance [ILCD], iris elevation) were measured on the 3, 6 and 9 o'clock meridians three times each. RESULTS: Statistically significant changes were noted in the following parameters: pupillary diameter, iris thickness 1 and 2, and TCPD were decreased, while ILCD was increased after pilocarpine. Wide chamber angles showed a tendency to become narrower and narrow ones to become wider after pilocarpine. CONCLUSION: One drop of pilocarpine caused significant changes in the anterior eye segment morphology. Not only the pupillary diameter decreased but iris thickness and trabecular-ciliary process distance were also decreased simultaneously. At the same time the contact surface between the lens and iris increased significantly. Ultrasound biomicroscopy gives new morphometric image information about the anterior eye segment which is not available using conventional gonioscopy or ophthalmic echography.

Administration, Topical↗

PubMed1982

The innervation pattern of crustacean skeletal muscle. Morphometry and ultrastructure of terminals and synapses.

The innervation pattern of distal muscle fibers of the opener muscle of walking legs of crayfish (Astacus leptodactylus) was investigated using methylene-blue staining, cobalt infiltration, and electron microscopy. A quantitative analysis of the entire innervation of single muscle fibers was attempted. It was found that instead of the generally assumed parallel array of numerous excitatory and inhibitory terminals, innervation consists of only a few branched terminals. The branches of excitatory and inhibitory terminals lie side-by-side. Both types are characterized by numerous varicosities (see Fig. 9B). The aggregate length of excitatory as well as inhibitory terminals on one muscle fiber is, on the average, about 1,500 micrometer with a total of 152 varicosities spaced about 10 micrometer apart. The average diameter of the varicosities is 4.26 micrometer, that of the connecting thin segments about 0.5 micrometer. Total terminal surface of motor or inhibitory terminals amounts to about 10,000 micrometers2 per muscle fiber. There are approximately 2,000 motor synapses on each muscle fiber, but their average total area is only about 6% of the terminal membrane area, or 0.06% of the (idealized) muscle fiber surface. There are conspicuous differences in the postsynaptic specializations associated with excitatory and inhibitory terminals; these are described in detail. The results are discussed in a functional context and with regard to design and results of electrophysiological experiments.

Animals↗

PubMed1984

Ultrastructure and morphometry of the stomach muscle of Amphiuma tridactylum.

An ultrastructural and stereological examination was performed on stomach smooth muscle of the salamander Amphiuma. This tissue has very large cells, ranging up to 12 X 1500 micron when relaxed. The extracellular space is 31% of the tissue volume, and the tissue contains 84.6% water. These values are similar to those of other amphibian and mammalian gastrointestinal smooth muscle. The cells possess the usual smooth muscle organelles. Thick, thin and intermediate filaments are present, along with membrane-associated and cytoplasmic dense regions. There is a well-developed sarcoplasmic reticulum and many microtubules. Caveolae are found in rows along the cellular surface; the caveolae increase the cellular surface area by about 70%. The ratio mean volume: surface area of the cells is 1.26 micron. This tissue appears to be typical of gastrointestinal smooth muscle, with the exception of the very large size of the cells.

Animals↗

PubMed1985

Morphometry of muscle fibre types in the carp (Cyprinus carpio L.). Relationships between structural and contractile characteristics.

Ultrastructural parameters of muscle fibre types of the carp (Cyprinus carpio L.) were measured and compared with their contractile properties. In red fibres, which are slower than pink fibres, the relative length of the junction between the T system and the sarcoplasmic reticulum (T-SR junction) is smaller and the Z lines are thicker than in pink fibres. Pink fibres have a smaller relative length of T-SR junction than white fibres from the axial muscles. The two types of red fibres present in carp muscle also differ in their relative lengths of T-SR junction. Significant differences in the relative areas of the SR were not found. The relative volume of myofibrils in red fibres is two-thirds that in pink fibres, a difference that is not reflected in the maximal isometric tetanic tensions of these types. Red fibres, which are less easily fatigued than pink fibres, have larger relative volumes of subsarcolemmal and intermyofibrillar mitochondria. Small pink fibres have a larger relative volume of subsarcolemmal mitochondria than large pink fibres, but have a similar relative volume of intermyofibrillar mitochondria. Small and large pink fibres differ in the relative volumes of their membrane systems, but have similar relative lengths of T-SR junction.

Actins↗

PubMed1987

The duct system of the avian salt gland as a transporting epithelium: structure and morphometry in the duck Anas platyrhynchos.

The duct system of the nasal salt gland of the duck comprises central central canals, secondary ducts and main ducts. The secondary and main ducts consist of a layer of columnar cells overlying a layer of small cuboidal cells. The columnar cells have complex intercellular spaces showing evidence of Na+K+-ATPase at the apical regions. Approximately 70% of surface area of the duct system is external to the gland. During adaptation to salt water the duct system increases in size as does the gland. Although the components of the gland of adapted ducks, including the duct system within the gland, increase in size compared with normal ducks, the percentage volume densities of the components remain similar in both categories of ducks, i.e. the duct system increases in size in proportion to the glandular tissue. The volume of the duct system external to the gland is six to seven times larger than the volume within the gland. Thus, if ductal modification of secreted fluid occurs, it will be most likely to take place in the ducts external to the gland. Total surface areas of the duct system were measured from serial sections of glands and ducts from one normal and one adapted duck. These were used to calculate possible flux rates of water and sodium across the duct epithelium, assuming the occurrence of either water reabsorption of sodium secretion. Although these flux rates are high it is shown that they are similar to calculated flux rates across the luminal surface of the secretory tubules.

Animals↗

PubMed1983

Morphometry of the small intestinal enterocytes of the fasted rat and the effects of colchicine.

The function of the microtubules that are present in the villus enterocytes of the mammalian small intestine is virtually unknown. In order to advance our knowledge about enterocyte microtubules, a quantitative ultrastructural comparison was carried out on enterocytes from rats injected intraperitoneally with colchicine (0.5 mg/100 g body weight) in saline and from rats injected with saline alone. Our morphometric and stereologic study demonstrates that colchicine treatment results in 1) an absolute decrease in microtubules, 2) a reduction in microvilli, essentially in length, 3) an increased thickness of the terminal web, 4) an increase in total lysosomal volume, apparently by an increased number of smaller lysosomes, and 5) a decrease in the number of Golgi lamellae. These results along with those from other studies suggest to us that enterocyte microtubules are involved in the biogenesis of microvillus plasma membrane. Our morphometric data from the saline-treated rats essentially agree with comparable data from other studies. However, comparison with comparable data from hamster enterocytes demonstrates species differences.

Animals↗

PubMed1979

Ultrastructural morphometry of blastogenesis I: transformation of small lymphocytes stimulated in vivo with dinitrochlorobenzene.

Changes in the volumes and surfaces of subcellular compartments of unstimulated small lymphocytes and immunoblasts in mouse axillary lymph nodes have been established using stereological techniques. Blast transformation was induced in vivo with dinitrochlorobenzene (DNCB). Cell samples were obtained by random sampling regimes applied at light and electron microscopic levels. From electron micrographs the volume densities of euchromatin, heterochromatin, nucleoli, mitochondria, Golgi apparatus and rough endoplasmic reticulum were determined. Cell surface/volume ratios were also computed. By estimating mean nuclear volumes using light microscopy, it was possible to calculate absolute compartmental volumes and to evaluate the plasma membrane surface areas of average cells. Transformation in this model was characterized by a considerable cellular hypertrophy and a substantial increase in plasmalemma surface. Hypertrophy was the consequence of increases in the volumes of all measured intracellular compartments, notably euchromatin and "residual cytoplasm" (including ground cytoplasm and free ribosomes). These changes are discussed in the context of the altered metabolic status of cells.

Animals↗

PubMed1986

Morphology and morphometry of motor endings in primate intrafusal fibers.

The pre- and postsynaptic structure of 243 axon terminals of bag 1, bag 2, and chain fibers were studied in cynomolgus monkey skeletal muscle spindles. The motor endings of the biceps and gastrocnemius spindles (long limb muscle) were compared to the motor endings of lumbricals and opponens pollicis (intrinsic hand muscle) spindles. In both muscle groups the only significant difference observed in the presynaptic features was in the presynaptic membrane length. The postsynaptic features of bag 1, bag 2 and chain endings were similar in the long limb muscle spindles. In the intrinsic hand muscle, however, the bag 1 and chain endings showed complex postsynaptic structure which resembled the extra fusal endings while the postsynaptic structure of bag 2 endings was much simpler. From these studies we conclude that the postsynaptic structure of various intrafusal fiber types is dissimilar in different muscles.

Animals↗

PubMed1983

Ultrastructural morphometry of the myocardium of Thunnus alalunga.

The common ventricle in the heart of the Thunnus alalunga was studied. The ventricular myocardium consists of an outer compact layer and a thick inner spongy layer. The compact layer has slightly larger cells (4-6 microns diameter) than the spongy layer (2.5-5 microns diameter). Ultrastructurally the myocardium displays normal arrangements of myofibrils and mitochondria. The sarcoplasmic reticulum is poorly developed. The intercalated discs are simple with the fascia adherens being the most frequent junctional type observed; occasionally a desmosome was seen. Nexus type junctions are present but are unassociated with the intercalated discs. There are no t-tubules evident but the plasmalemma exhibits numerous caveolae which rarely form couplings with the sarcoplasmic reticulum. A morphometric analysis of the volume percent of mitochondria and myofibrils showed that the myocardial cells in the spongy layer of the heart have a significantly greater volume percentage of mitochondria than the compact layer. No significant differences were found between myocardial regions when the volume percentages of myofibrils were compared. The physiological studies revealed that the albacore tuna has heart rates (120 bpm) and ventricular blood pressures (100 mmHg) that are among the highest reported for fish.

Animals↗

PubMed1994

Sciatic nerve morphology and morphometry in mature rats with streptozocin-induced diabetes.

Controversy exists as to the morphological and morphometric changes seen in experimental diabetic neuropathy (EDN). Most previous studies have utilized immature animals, with controversy as to whether the observed changes are due to maturational delays induced by hyperglycemia, or to diabetes per se. This study utilizes mature 9-month-old Sprague-Dawley rats. Six control and six hyperglycemic rats were examined 24 weeks after streptozocin injection. No morphological abnormalities were seen in the sciatic nerve at the light microscopy level. Total fascicular area and myelinated fiber density showed no significant differences (ANOVA, P > 0.05). No significant differences [ANOVA, P > 0.05 and Kolmogorov-Smirnoff (K-S), P > 0.05] between control and diabetic groups were shown for fiber, axon, and myelin areas, fiber and axon diameters, and myelin thickness. Fiber index of circularity, axon index of circularity, and g ratio were not significantly different with ANOVA (P > 0.05), but the diabetic group showed significantly lower values (P < 0.001) with K-S testing. Regression analyses of axonal area and log(n) axonal area plotted against myelin thickness showed no significant differences between the control and diabetic animals. This study in mature rats confirms the relative lack of morphological and morphometric changes in EDN which have previously been reported in studies involving immature rats. It highlights the difficulties in trying to extrapolate from EDN to human diabetic neuropathy where severe morphological and morphometric abnormalities may be present.

Animals↗

PubMed1995

Horizontal plane morphometry of normal and scoliotic vertebrae. A methodological study.

Computed tomography (CT) scans are widely used for quantification of the morphology of the vertebral body and of the changes of the thoracic cage in the horizontal plane in scoliosis. So far, however, no method exists for precise quantification of the parameters of the posterior elements. We present a method for quantification on the basis of CT scans of different parameters of the morphology of both the vertebral body and posterior elements in the horizontal plane. The precision and accuracy of the method were estimated in a model study by CT scanning of a normal and a scoliotic vertebra in different, controlled, tilted positions. Moreover, in a clinical study CT scans of 19 thoracic vertebrae from non-scoliotic subjects and the apex vertebra from 40 scoliotic subjects were selected to test the applicability of the method to clinical studies. The intra- and interobserver variation of the measurements was analysed. The angle between the longitudinal axis of the vertebral body and that of the whole vertebra was used to evaluate the asymmetry of the vertebral body. The right to left pedicle width index, the right to left hemi-canal width index and the index of transverse process angles related to the axis of the vertebra were used to quantify the asymmetry of the posterior elements. The results indicate that, except for the pedicle width index, the variables under study were not significantly influenced by a 5 degrees or 10 degrees tilt ventrally, dorsally, or laterally of either the normal or the scoliotic vertebra. Hence, the method can be satisfactorily applied to longitudinal group comparisons.(ABSTRACT TRUNCATED AT 250 WORDS)

Anthropometry↗

PubMed1995

Vitamin E stimulates trabecular bone formation and alters epiphyseal cartilage morphometry.

The effects of dietary vitamin E (VIT E) and lipids on tissue peroxidation and fatty acid composition, epiphyseal growth plate cartilage development, and trabecular bone formation were evaluated in chicks. A 2 x 2 factorial design was followed using two levels (30 and 90 IU/kg of diet) of dl-alpha-tocopheryl acetate and two different dietary lipids. The basal semipurified diet contained one of the following lipid treatments: anhydrous butter oil (40 g/kg) + soybean oil (60 g/kg), [BSO], or soybean oil (100 g/kg), [SBO]. After 14 days of feeding, the level of alpha tocopheryl in plasma was higher and thiobarbituric acid reactive substances (TBARS) were less in plasma and liver of chicks supplemented with 90 IU of VIT E compared with those given 30 IU of VIT E. Body weights and tibiotarsal bone lengths were not affected by the dietary treatments. Saturated fatty acids (14:0, 15:0, 16:0, 17:0, and 18:0) were increased in the tibiotarsal bone of chicks fed the BSO diet. In contrast, total polyunsaturated fatty acids and the ratio unsaturated fatty acids/saturated fatty acids were higher is plasma of chicks fed SBO compared with the values from chicks fed BSO. The thickness of the entire growth plate cartilage and the lower hypertrophic chondrocyte zone was significantly greater in chicks fed 90 IU/kg of VIT E. Kinetic parameters on bone histomorphometry indicated that mineral apposition rate was higher in chicks fed 90 IU of VIT E. The interaction effect between the VIT E and BSO treatments led to the highest trabecular bone formation rate among the groups. These data suggest that VIT E protects against cellular lipid peroxidation in cartilage to sustain normal bone growth and modeling.

Animals↗

PubMed1986

Immunohistochemistry and morphometry of gastrin cells in the rat pyloric antrum during starvation.

The gastrin cells (G cells) in the rat pyloric antrum after 7, 14, 21 and 28 days of starvation were investigated by immunohistochemistry and electron microscopy. In the peroxidase anti-peroxidase method for light microscopy, gastrin immunoreactive cells during starvation markedly decreased in number and size. Quantitative electron microscopy revealed that during starvation the number of electron-lucent granules were greatly reduced, but the number of electron-dense granules increased; the number of intermediate granules were not remarkably changed in G cells. These results may suggest that the synthesis of gastrin and granule maturation were greatly inhibited during long-term starvation.

Animals↗

PubMed1993

Ultrastructure and morphometry of testicular Leydig cells and the interstitial components correlated with testosterone in aging rats.

The ultrastructure of testicular interstitium in young and aged adult rats was analysed using morphometric methods, and the plasma testosterone concentration was measured. With increasing age there was an augmentation in the volume of collagen fibrils in the intercellular matrix and in blood vessels. During the aging process (approximately two years) the average volume of the Leydig cell decreased from 1364 microns 3 to 637 microns 3, but the number of Leydig cells in paired testes increased from 53 x 10(6) to 113 x 10(6). The absolute volume of smooth surfaced endoplasmic reticulum (SER) per Leydig cell amounted in aged rats to 78% of that in young adult rats. The total amount of SER in paired testes increased by 62% with aging. The present analysis suggests that the ability of SER to maintain peripheral testosterone concentration decreases with age. In young adult rats the absolute volume of peroxisomes per Leydig cell correlated significantly with the concentration of testosterone in blood and also with the absolute volume of SER per Leydig cell. These results combined with ultrastructural observations of close apposition of peroxisomes and SER suggest that peroxisomes have a role in testosterone secretion by Leydig cells.

Aging↗

PubMed1986

The transverse tubular system of rat myocardium: its morphology and morphometry in the developing and adult animal.

The three dimensional arrangements of the T system in the developing and adult animal were investigated by means of high voltage electron microscope stereoscopy using Golgi treated materials. The rat myocardial T system was composed of three major group elements: the transverse tubules, longitudinal tubules and flattened cisternae, which were classified according to their orientation and to their morphological features. It was found, as the growth of the rats proceeded, that the longitudinal tubules increased in number and that the transverse tubules were arranged more regularly and densely at the level of the z band. The flattened cisternae transiently increased in number during the 2-9 weeks, and then decreased gradually. Electron microscopy also revealed that all the transverse, longitudinal tubules and flattened cisternae of the T system had the chance of forming a coupling with the sarcoplasmic reticulum irrespective of its morphology and orientation to the myofibrils. Quantitative analysis of the rat T system from the stereo images indicated that the surface area (0.299 micron2/micron3) was considerably greater than previously reported.

Age Factors↗

PubMed1992

Relationship between tissue reactions and morphological changes of the fungi in chromoblastomycosis: morphometry and electron microscopy.

To investigate the histological distribution and the morphology of the fungi and the tissue reactions in chromoblastomycosis, especially in the process of transepidermal elimination, cutaneous lesions of two patients with this disease were studied morphometrically and ultrastructurally. In the dermis, most of the fungal elements appeared as sclerotic cells and their cell wall showed an irregular, worm-eaten leaf-like appearance; they seemed to be continuously attacked by polymorphonuclear neutrophils. The epidermis eliminated 10-20% of all the organisms in the skin lesions, and the hypha-forming activity tended to be higher in the epidermis than in the dermis. Ultrastructurally, basal keratinocytes facing the dermal abscess containing fungal elements frequently appeared as dark cells, suggesting an increased proliferation activity. Spinous keratinocytes facing intraepidermal microabscesses containing fungal elements showed an abnormal accumulation of tonofilaments and further early keratinization in the spinous cell layer. All of the morphological changes of the dermis and epidermis are regarded as defence reactions against the fungi existing in the skin lesions. There is a close relationship between tissue reactions and morphological changes of fungi in chromoblastomycosis.

Aged↗