摘要:

AbstractMuscle spindles in the soleus of 1‐year‐old dystrophic mice of the C57BL/6J dy2J/dy2Jstrain were studied by microscopic and morphometric methods, and comparisons were made with those in age‐matched normal tissue. Transverse epon sections were cut through various regions of an individual receptor, and subsequent 90° reorientation enabled longitudinal examination of the same spindle. In dystrophy, alterations were detected in the outer capsule and consisted of a significant increase in its overall thickness in equatorial regions. Perineurial proliferation accompanied histiocyte and collagen infiltration. Within the equator, intrafusal fibers and sensory terminals appeared unaffected by dystrophy. Alterations in the intrafusal fibers were restricted to polar zones where the mean diameters of chain and bag fibers were significantly reduced. Polar chain fibers exhibited a greater degree of atrophy in dystrophy with a 40% diminution in size. Ultrastructural changes in intrafusal fiber polar regions were less pronounced compared to the surrounding dystrophic muscle. Mitochondrial alterations in affected intrafusal fibers included intramatrix inclusions and glycogen deposition. Vacuolization of the sarcoplasmic reticulum and subsarcolemmal tubular aggregates were also observed in polar regions of dystrophic chain fibers. Regional variation in spindle involvement in advanced murine dystrophy provides evidence that the equatorial contents of this receptor are sequestered from the deleterious effects of the disease. Capsular thickening in the equator may be an adaptive response, preventing the intrafusal fibers from undergoing the moderate change and atrophy observed at their pola

ISSN:0003-276X    

DOI:10.1002/ar.1092160202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractA protein of approximately 28,000 relative molecular mass (Mr) cross‐reacting with antiserum against the 28,000‐Mrrat renal calcium‐binding protein (calbindin‐D28k) has been localized in the kidney of a salientian amphibian,Rana catesbeiana. Cells reactive for calbindin‐D28kwere found in the distal tubule at all stages of metamorphosis by the unlabeled antibody peroxidase‐antiperoxidase technique. Adult kidneys appeared to have more calbindin‐D28k‐positive cells. The renal corpuscle, neck, and proximal tubule were negative. An immunoreactive 28,000‐Mrband that comigrated with the band of calbindin‐D28kwas visualized by the immunoblot technique. The finding of the 28,000‐Mrcalbindin‐D in the anamniotic kidney demonstrates that this calcium‐binding protein (CaBP) is phylogenetically older than our previous studies of higher vertebrates had revealed (Rhoten et al., 1985). Although the function of calbindin‐D28kin the distal nephron is unknown, this CaBP can now be presumed to have functional significance in the mesonephric as wel

ISSN:0003-276X    

DOI:10.1002/ar.1092160203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractThe effects of starvation on glucose 6‐phosphatase (G6Pase; EC 3.1.3.9., D‐glucose 6‐phosphate phosphohydrolase) and glycogen phosphorylase (EC 2.4.1.1.) activities, and on glycogen content, were studied in skeletal muscles (m. rectus femoris) of mice. In the muscle cells from fed animals, the cytochemical reaction product for G6Pase activity was observed in moderate amounts in the terminal cisternae of sarcoplasmic reticulum and in small amounts in the nuclear envelope, and was rare or absent in the intermyofibrillar sarcoplasmic reticulum. After 4 days of starvation, however, the reaction product became abundant in all of the terminal cisternae, intermyofibrillar sarcoplasmic reticulum, and nuclear envelope. Biochemical G6Pase and glycogen phosphorylase a (active form) activities were higher in the muscles of starved mice than in those of fed animals. The glycogen content decreased markedly in the muscles of starved mice. The results suggest that the role of the increased G6Pase in skeletal muscle cells of starved mice is to release glucose into the blood by hydrolyzing glucose 6‐phosphate produced through the increased phosphorylase a

ISSN:0003-276X    

DOI:10.1002/ar.1092160204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractAfter aldehyde‐tannic fixation, Zinc‐iodine‐osmium fixation, Phospho Tungstic acid‐chromium stain and two cytochemical reactions, the ultrastructure of the Golgi complex of early spermatids in the guinea pig reveals two different regions. One, close to the cell surface, involves endoplasmic reticulum (ER), intermediate vesicles, and Golgi outer cisternae and has membranes of uniform thickness and symmetrical trilaminar pattern, a strong ZIO precipitate, and an almost negligible cytochemical reaction to polysaccharides and cholesterol. The other region, close to the nucleus, exhibits thicker, sometimes asymmetric membranes, a polygonal network coating the thick cisterna, condensing vacuoles and areas of the acrosomal membrane, an intense reaction to polysaccharides and cholesterol, and packages of different densities in the condensing vacuoles and acrosome. This work also shows the coincidence of the cytochemical marker of cholesterol with the polygonal coating of clathrin in the condensing face of th

ISSN:0003-276X    

DOI:10.1002/ar.1092160205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractThis study describes the morphologic features of uterine glandular epithelium in human basal plate at term and identifies this epithelium as an active site of glycoprotein synthesis. Wedge biopsies were obtained from the basal plate at the time of repeat cesarean section from 11 normal pregnant patients at term. Biopsy specimens were either processed immediately for microscopic examination or incubated in vitro with 25μCi/cc of3H‐galactose or3H‐leucine. Tissues incubated with tritiated compounds (2‐hour pulse ± 3‐hour chase in nonradioactive medium) were either processed for light microscopic autoradiographic analysis or extracted for determination of trichloroacetic‐acid‐precipitable tritiated macromolecules in tissues and medium. Profiles of cuboidal‐columnar glandular epithelium were identified in the decidual component of the basal plate region adjacent to spiral arterioles and perpendicular to the inner layers of myometrial muscle. Autoradiographic and biochemical studies identified the glandular epithelium, as well as large decidual cells, to be major sites of incorporation of both3H‐galactose and3H‐leucine and to be prime sources for secretion of tritiated macromolecules that appeared in the medium during in vitro incubation of basal plate tissue. Ultrastructurally, the glandular epithelium was noted to rest on a basal lamina, to have lateral cell membranes with numerous desmosomes, and to exhibit an apical surface with microvilli projecting into a luminal space. Cytologic features of the cells included abundant profiles of rough endoplasmic reticulum, multiple mitochondria with lamellar cristae, a well‐developed perinuclear but nonpolarized Golgi apparatus, and nuclei containing predominantly euchromatin. Lipid droplets and glycogen deposits were present in some cells. This study indicates that uterine glands persist throughout human gestation in the basal plate and that these glands continue to be active in glycoprotein sy

ISSN:0003-276X    

DOI:10.1002/ar.1092160206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractDuring postnatal growth the parenchymal septa of rat lung undergo an impressive restructuring. While immature septa are thick and contain two capillary layers, mature septa are slender and contain a single microvascular network. Using the Mercox®casting technique and scanning electron microscopy, we investigated the mode and the timing of the transformation of the pulmonary capillary bed. During the third postnatal week the parenchymal septa rapidly mature to match adult morphology. Even in adult lungs, however, remnants of the immature status are present: A capillary bilayer is regularly found at the base and the tip of the septa. Our observations support the concept that reduction of intervening tissue, partial fusion of the two capillary networks, and preferential growth lead to the mature vascular arrangement. The fact that true mature interalveolar septa show a denser capillary network than alveolar walls abutting onto pleura, bronchi, or larger vessels is consonant with the fusion theory. Towards the nonparenchyma, the capillary network surrounding every airspace had no counterpart to fuse with.From quantitative data it can be calculated that owing to lung growth, mesh size should increase more than four times between birth and adult age. The adult lung network, however, is denser than the one in young animals. This means that new meshes must be added during growth. We propose that small holes observed in sheet‐like regions of the microvascuiature enlarge to form new capillary meshes. With this mechanism of in‐itself or intussusceptional growth, sprouting of individual capillary segments to increase network size is no longer ne

ISSN:0003-276X    

DOI:10.1002/ar.1092160207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractA combined ultrastructural and immunocytochemical study was performed on the pineal gland of the horse in order to identify the cell types present and describe their characteristics. Comparisons have been made with other mammals. Two main cell types are present: pinealocytes and glial cells. Pinealocytes display different degrees of electron density in the nucleus and the cytoplasm, yet no ultrastructural feature supports the idea of separate populations. Putative secretory materials are stored in vesicles related to the Golgi apparatus. A variety of electron‐dense bodies are present in the cytoplasm. Interstitial cells responding to anti‐GFAP (glial fibrillary acid protein) and anti‐vimentin antibodies, but not to anti‐neuronal 200‐kD protein antibodies, are located close to the perivascular spaces and connective septa. Morphological and immunocytochemical features support classifying them as astrocytes, probably protoplasmic. The presence of a cavity lined with pericytes, putatively a remnant of the embryonic lumen of the organ, is a consistent finding and may relate to the third

ISSN:0003-276X    

DOI:10.1002/ar.1092160208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractThe effect of aging on the formation of C cell follicles was examined in the thyroid gland of guinea pigs at various ages ranging from 1 to 29 months. The C cell follicles were demonstrated with the immunoperoxidase methods by using anticalcitonin and antisomatostatin antisera and with PAS reaction. They were already detected in 1‐month‐old guinea pigs but in low number. Thyroid glands from 1‐ to 14‐month‐old animals contained only a small number of C cell follicles and did not reveal the age‐related increase. In aged guinea pigs (20‐ to 29‐month‐old), a dramatic increase of C cell follicles was found, about 13 times as high as the number of other age groups. The C cell follicles through all age groups were present in large clusters of C cells. In the aged guinea pigs, nodular large aggregates of C cells regarded as C cell hyperplasia occurred and numerous C cell follicles were formed in the large cell aggregates. Thus, the conspicuous increase of C cell follicles in aged animals was associated with a proliferative abnormality of C cells. The C cells forming follicles showed moderate to weak immunoreactivity for calcitonin, whereas they showed very intense immunoreactivity for somatostatin. In addition, the colloidlike and flocculent materials stored in the follioular lumina, which were consistently PAS‐positive, were weakly immunoreactive to somatostatin but nonrea

ISSN:0003-276X    

DOI:10.1002/ar.1092160209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractThe ultrastructural distribution of complex carbohydrates in an early formation stage of rat incisor enamel was investigated by staining with the periodic acid‐thiocarbohydrazide‐silver proteinate reaction (PA‐TCH‐SP) for vicinal glycol‐containing glycoconjugates, the phosphotungstic acid‐chromic acid mixture (PTA) for glycoproteins, and the cationic dyes alcian blue or bismuth nitrate for sulfated glycoconjugates. In order to remove selectively sulfated complex carbohydrates, half of the serial sections obtained were digested with a bovine testicular hyaluronidase prior to staining.Far fewer electron‐dense deposits were observed with the PA‐TCH‐SP method on hyaluronidase‐treated sections, especially those subsequently treated for 48 hours with TCH. On the other hand, the minimal staining obtained with PTA was much more intense on sections treated with hyaluronidase where linear fiberlike structures were observed. With cationic dyes, staining of dotlike alignment structures and ground substance was obtained but was completely abolished by hyaluronidase treatment. Cuprolinic blue in a critical electrolyte concentration, ruthenium hexamine trichloride used with aldehyde during fixation, as well as rapid‐freezing followed by freeze‐substitution validate that this dotlike distribution is not an artefact of processing.The staining results demonstrated that the glycoproteins and sulfated complex carbohydrates in developing rat incisor enamel each display a specific distribution pattern. The glycoproteins were present as fiberlike structures and the sulfated carbohydrates appeared as dotlike formations located close to the surface of the fiberlike structures, and/or in

ISSN:0003-276X    

DOI:10.1002/ar.1092160210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractThe aim of this study is to document the prenatal stages of development of the flexion creases on the surfaces of the human palm, sole, and digits. We used 160 human fetuses, 6–20 weeks of gestational age, to observe the morphological features of the hand and foot, as well as the period and location of the appearance of the flexion creases. We found that most creases develop concurrently with the appearance of the fetal volar pads and the rest develop independently of them. Furthermore, with some exceptions, the creases seem to develop independently of the flexion movements of hand and foo

ISSN:0003-276X    

DOI:10.1002/ar.1092160211

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY