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Volume 23 (1990)
- Issue 6 Pages 753-
- Issue 5 Pages 601-
- Issue 4 Pages 427-
- Issue 3 Pages 261-
- Issue 2 Pages 139-
- Issue 1 Pages 1-
Volume 23, Issue 6
Displaying 1-8 of 8 articles from this issue
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TOHRU NAKANO, TOYOSHI FUJIMOTO, HIROTAMI KOIKE, KAZUO OGAWA1990 Volume 23 Issue 6 Pages 753-767
Published: 1990
Released on J-STAGE: October 28, 2009
JOURNAL FREE ACCESSAn analytical color fluorescence electron microscope (ACFEM) based on a high-resolution scanning electron microscope has been developed. The ACFEM enables us not only to detect cathodoluminescence (CL), which is a weak luminescence signal under electron beam bombardments, as color images, but also to analyze CL spectra. A cryo-SEM method was introduced to prevent beam effect on biological specimens. In experiments 1 and 2, we observed adult rat retinas under different conditions: hyper- and hypovitaminosis A and light and dark adaptation, which revealed that the distribution of vitamin A ester and its change under these conditions could be detected in situ by the ACFEM. In experiment 3, postnatal development of rat retina was observed under the ACFEM up to 3 weeks after birth. The retinal pigment epithelial cells of new born rats were already functioning as vitamin A storing cells. On the other hand, vitamin A ester in the developing outer segment first appeared on the 13th postnatal day, which suggests a correlation to the development of visual function. These results show that CL analysis by the ACFEM is a simple and effective new method in the field of histo- and cytochemistry.View full abstractDownload PDF (10066K) -
TOHRU NAKANO, TOYOSHI FUJIMOTO, HIROTAMI KOIKE, KAZUO OGAWA1990 Volume 23 Issue 6 Pages 769-780
Published: 1990
Released on J-STAGE: October 28, 2009
JOURNAL FREE ACCESSRat adrenal glands under several different conditions were observed under the analytical color fluorescence electron microscope (ACFEM) to elucidate the origin of the cathodoluminescence (CL) of adrenocortical cells. In the control group, blue-green CL which has two peak wavelength at 320nm and 430nm was observed to be emitted from lipid droplets of adrenocortical cells. When hypocholesterolemic drugs, 17α-ethinyl estradiol and 4-aminopyrazolo-pyrimidine, were administered, CL of 320nm was observed to disappear in all three zones of the adrenal cortex. On the contrary, in hypophysectomized rat adrenal cortices, CL of 320nm significantly increased, and that of 430nm diminished. In the ACTH-treated group, CL of 320nm in the zonae fasciculata and reticularis was observed to fade up to 2hr after injection, while that in the zona glomerulosa remained. These results suggest that CL of 320nm in adrenocortical cells is derived from cholesterol ester stored for steroidogenesis, and showed that the CL analysis using the ACFEM in combination with the cryo-SEM method is superior to conventional histochemical technique in simplicity, specificity, and preservation of ultrastructure.View full abstractDownload PDF (13985K) -
TOSHIKAZU TANAKA, MASAHIRO SAKAI, KAZUSHI FUJIMOTO, KAZUO OGAWA1990 Volume 23 Issue 6 Pages 781-792
Published: 1990
Released on J-STAGE: October 28, 2009
JOURNAL FREE ACCESSIn order to investigate the ultrastructural and quantitative changes of gap junctions in the lens associated with cataract formation, the lenses of ICR (Ihara cataract rat)-strain rats which invariably develop cataracts and of Wistar rats were analyzed morphometrically. Gap junctions were observed abundantly in lenses of normal Wistar rats. In lenses of ICR-strain rats, it became difficult to detect gap junctions in accordance with cataract formation. However, no notable differences were detected in the ultrastructure of gap junctions between both lenses of control and ICR-strain rats. Morphometric analysis revealed that the ratio of total length to cell circumference at 4 weeks of age (before cataract formation) is mostly equal to that of age-matched controls (11%). The ratio decreased to 7% for 9-week-old ICR-strain rats (just beofre cataract formation) and 2% for 16-week-old ICR-strain rats (after cataract formation). These results suggest that the decrease in size and frequency of gap junctions prior to cataract formation may be linked with the steps leading to cataractogenesis.View full abstractDownload PDF (12412K) -
TOSHIKAZU TANAKA, MASAHIRO SAKAI, KAZUO OGAWA1990 Volume 23 Issue 6 Pages 793-804
Published: 1990
Released on J-STAGE: October 28, 2009
JOURNAL FREE ACCESSCytochemical localization and biochemical quantification of acid phosphatase (ACPase) activity were demonstrated in order to investigate the possible role of lysosomal enzymes in the process of cataract formation. ICR-strain and Wistarstrain rat (for the control experiment) were employed as experimental animals. Lenses of both groups of rats at 7 weeks and 16 weeks of age were fixed in 2% glutaraldehyde, 2% formaldehyde in 0.1M cacodylate buffer. After rinsing overnight in the same buffer, 20μm sections were made and incubated at 37°C in a modified Gomori's medium. ACPase activity was also assayed biochemically using p-nitrophenyl phosphate as substrate. In all lenses, ACPase activity was detected mainly in the epithelium. In the anterior and posterior superficial cortex, ACPase activity was infrequently detected within lysosomes and intercellularspaces were free of reaction products in lenses of control rats. In pre-cataractous lenses (7-week-old ICR-strain rats), ACPase activity was generally more intense than that in lenses of control rats. Interestingly, reaction products were scattered in the posterior superficial cortical layer adjacent to the capsule. By contrast, reaction products in advanced cataractous lenses (16-week-old ICR-strain rats) were scarcely detected in the posterior region which was highly damaged. These results were congruent with the level of ACPase activity assayed biochemically. From the fact that there was not a continuous increase of ACPase activity, we inferred that the increase of ACPase activity might not be a direct initiator of cataract formation in this rat.View full abstractDownload PDF (13301K) -
JUNG NAM LEE, NOBUKAZU ARAKI, YOICHIRO TAKASHIMA1990 Volume 23 Issue 6 Pages 805-816
Published: 1990
Released on J-STAGE: October 28, 2009
JOURNAL FREE ACCESSCat+-ATPase activity in rat pancreatic exocrine cells and endocrine cells during perinatal development was cytochemically examined at the electron microscopic level. The intense enzyme activity on the plasma membrane of endocrine cells was observed from the beginning of differentiation of endocrine cells, as well as in adult rats. However, no activity was seen on the plasma membrane of exocrine cells in prenatal rats. Ca2+-ATPase activity on the basolateral plasma membrane of exocrine cells appeared after birth, whereas pancreatic acini and zymogen granules were fully developed during the late embryonic stage. It seemed that the appearance of Ca2+-ATPase activity on the plasma membrane corresponded to the beginning of exocrine secretory function. These results suggest that Ca2+-ATPase activity on plasma membrane of exocrine cells may be deeply involved in the secretory function and/or its regulation.View full abstractDownload PDF (10833K) -
TAKEO AIDA, HIROYUKI YAMADA, GORO ASANO1990 Volume 23 Issue 6 Pages 817-824
Published: 1990
Released on J-STAGE: October 28, 2009
JOURNAL FREE ACCESSAn experimental model of liver fibrosis was used to study the expression of type IV procollagen and prolyl 4-hydroxylase mRNAs by in situ hybridization. Paraffin sections of rat liver tissue were examined using non-radioactive digoxigenin-labeled cDNA probes and in situ hybridization employing mouse α1 (IV) procollagen cDNA and chicken prolyl 4-hydroxylase β-subunit cDNA in order to identify cells responsible for the production of type IV procollagen and prolyl 4-hydroxylase mRNAs after administration of carbon tetrachloride (CCl4). Localization of type IV procollagen and prolyl 4-hydroxylase mRNAs was demonstrated in the cytoplasm of mesenchymal cells after six weeks of CCl4 administration. Type IV procollagen and prolyl 4-hydroxylase mRNAs were noted in hepatocytes after eight and ten weeks respectively. The expression of type IV procollagen mRNA was found in a large number of hepatocytes in proportion to the extent of fibrosis. These results suggest that in addition to the mesenchymal cells, hepatocytes also play an important role in fibrogenesis of the liver.View full abstractDownload PDF (6476K) -
SHUZHEN YANG, DANYUN LU, SUFAN LI, GANG CHEN1990 Volume 23 Issue 6 Pages 825-830
Published: 1990
Released on J-STAGE: October 28, 2009
JOURNAL FREE ACCESSBy applying a histochemical method to demonstrate the myosin ATPase activity of the skeletal muscle of humans and rats after preincubation in acidic and alkaline media, the muscle fiber types could be identified. The human skeletal muscle fibers can be classified into 4 types (I, IIa, IIb and IIc). The rat skeletal muscle fibers can be distinguished into 5 types (Ia, Ib, IIa, IIb and IIc). By using 12 kinds of histological and histochemical staining methods, we studied the activities of several enzyems and their staining patterns in the various types of muscle fibers, and then calculated the percentage of each fiber type in humans.View full abstractDownload PDF (1918K) -
MARCO BIGGIOGERA, ELDA SCHERINI, VLADISLAV MAREŠ1990 Volume 23 Issue 6 Pages 831-839
Published: 1990
Released on J-STAGE: October 28, 2009
JOURNAL FREE ACCESSWe have used cis-dichlorodiammine platinum II (cis-DDP) to induce apoptosis in germinative compartment of the external granular layer of rat cerebellum which is most sensitive to acute treatment with this drug. Ten-day-old animals were injected with 5μg/g b. w. and killed after 2, 4, 8, 16 or 24hr and the molecular architectonics of apoptotic cell nuclei was studied at the electron microscopy level. A Feulgen type reaction with osmium ammine complex (OAC) and a proteolytic treatment with pronase were used for EM cytochemistry. The data show that at the onset of apoptosis most of the OAC-stained DNA was located at the periphery of the nucleus, where heterochromatin masses accumulate. In the center of the nucleus, only thin fibers and small aggregates of DNA were detected. At later stages of apoptosis, the OAC-stained DNA was randomly distributed in dense roundish masses or clumps near the nuclear membrane surrounding a central OAC-negative area. Treatment of serial sections with pronase and EDTA regressive staining for RNPs revealed that the OAC-negative areas were mainly composed of nuclear proteins and RNPs.View full abstractDownload PDF (10823K)
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