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Volume 26 (1993)
- Issue 6 Pages 507-
- Issue 5 Pages 337-
- Issue 4 Pages 251-
- Issue 3 Pages 165-
- Issue 2 Pages 75-
- Issue 1 Pages 1-
Volume 26, Issue 3
Displaying 1-11 of 11 articles from this issue
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KUNIAKI TAKATA, MICHIHIRO KASAHARA, YOSHITOMO OKA, HIROSHI HIRANO1993 Volume 26 Issue 3 Pages 165-178
Published: 1993
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSSugar transporters are integral membrane proteins that transport sugars across cellular membranes. Recent advances in molecular biology have revealed two major families of them: the Na+-dependent glucose transporter (SGLT) family, and the facilitated-diffusion glucose transporter (GLUT) family. At least three isoforms of SGLT and six of GLUT have been identified so far. Expression of specific isoforms depends on the type of cell, tissue, or organ, and the physiological and pathological conditions. Their precise localization at the specific domain (s) of the plasma membrane or in the intracellular organelles is closely related to their cellular functions. In this review, their localization and link to specific cellular functions are addressed in the following cases: active transepithelial transport of glucose; glucose transport in blood-tissue barriers; possible role of glucose transporter and the gap junction in the transepithelial transport of glucose; the contribution of glucose transporters in the regulation of blood glucose level; and localization of glucose transporters at specific plasma membrane domains.View full abstractDownload PDF (13672K) -
YOSHIKO ITOH, JOHBU ITOH, R. YOSHIYUKI OSAMURA, KEIICHI WATANABE, R.H. ...1993 Volume 26 Issue 3 Pages 179-183
Published: 1993
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThe distribution of PAM was studied immunohistochemically at light and electron microscopic levels in the endocrine organs of mature male rats. PAM was found in the anterior pituitary gland, thyroid C cells, the gastrointestinal tract, the pancreas, and the adrenal medulla. For light microscopic immunohistochemistry, fixative B (pH 4 Bouin's) and paraffin embedding were satisfactory with SDS treatment preceding immunohistochemical staining. But PAM in the thyroid C cells could be detected only by frozen sections after Zamboni fixation. By the immunoelectron microscopy pre-embedding method, PAM was localized in secretory granules suggesting the site of a-amidation in secretory granules. Our studies emphasized the role of the secretory granules in posttranslational processing not only in proteolytic digestion but also in α-amidation.View full abstractDownload PDF (4550K) -
TOSHIMITSU WATABIKI, TAKUMA TOKIYASU, MANABU YOSHIDA, NORIAKI ISHIDA, ...1993 Volume 26 Issue 3 Pages 185-188
Published: 1993
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSA simple procedure, called the “cold acetone (-70°C) -dropping affixation technique”, for affixing fresh, frozen sections to cold, clean, untreated glass slides is described. A few drops of absolute acetone (-70°C) were dropped with a precooled pipet to the sections placed on the slides, and the acetone on the slides was absorbed immediately with a cold filter paper. The slides with the sections were left in a cryostat for approximately 30 min, so that the sections were affixed firmly to the slides. By this method we could prevent the diffusion of low-Km aldehyde dehydrogenase (ALDH) from the sections.
The localization of low-Km ALDH activity in the hepatic lobule of normal mice was studied histochemically with the nitroblue tetrazolium (NBT) method. Reaction products, purplish-blue formazan showing the enzymatic activity, were found mainly in the centrilobular zone. Cyanamide (5 mM) inhibited the low-Km ALDH activity, whereas the high-Km ALDH activity was unaffected even by 10 mM cyanamide.View full abstractDownload PDF (2939K) -
KANKATSU YUN, KOENRAAD A.L. DE SMET1993 Volume 26 Issue 3 Pages 189-195
Published: 1993
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSNorthern blot hybridization was carried out to detect insulin mRNA in a variety of tissues of Wistar rats using isotopic cDNA or 17-mer oligonucleotide probes. The insert of pCRI-354, containing rat insulin I cDNA, was labelled by the random primer method using α- [32P] -dATP. The result gave a single transcript of 500-650 nucleotides. Oligonucleotide probes, on the other hand, showed no specific hybridization signal in association with a high background.
In situ hybridization was carried out to localize insulin mRNA in the pancreas of Wistar rats using isotopic or non-isotopic cDNA probes. The insert of pCRI-354 was labelled by the same method using either α-32P-dATP or biotin-11-dUTP. Hybridization was performed under two different conditions, i. e., either moderate or low stringency. Autoradiography was performed for isotopic probes, while streptavidin alkaline phosphatase followed by a NBT-BCIP reaction was applied for biotinylated probes. Results indicated that both isotopic and biotinylated cDNA probes showed a specific signal over β-cells of pancreas islets. The more stringent hybridization condition gave a reduced signal with less background compared to the moderate one. In situ hybridization using oligonucleotide probes gave somewhat an ambiguous result where probes appeared to hybridize non-specifically to cytoplasmic RNA.View full abstractDownload PDF (10292K) -
JOSE FIGUEREDO DA SILVA, TAKANORI HOSOKAWA, TERUHIKO OKADA, TOSHIHIRO ...1993 Volume 26 Issue 3 Pages 197-202
Published: 1993
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThe electron microscopic localization of the acetylcholinesterase (AChE) activity in the mouse heart was studied by the method of Tago et al. (1986). The results showed deposition of reaction product only in nerve elements: some neurons of the intrinsic atrial ganglia and atrial and ventricular nerve fibers. The AChE activity was particularly localized in the synaptic clefts. In contrast with previous reports describing the existence of “internal” ChE, no activity was detected within myocardial cells.View full abstractDownload PDF (9503K) -
PUNG-PUNG HWANG, SY-WEN WANG1993 Volume 26 Issue 3 Pages 203-211
Published: 1993
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSProtein A-gold method was used for cytochemical localization of prolactin (PRL) in the secretory cells in the tilapia (Oreochromis mossambicus) pituitary. Antiserum to chum salmon prolactin (sPRL) was used for this study. Effects of fixation on the antigencity of PRL were examined, and the antigenicities of PRL in pituitaries of seawater (SW) -and freshwater (FW) -adapted tilapia were compared.
The antiserum to sPRL reacts selectively only with the secretory granules in the specific cells, i, e., the presumptive PRL cells, in the rostral pars distalis, but never reacts with the other cellular compartment of the PRL cells nor with other cell types in the tilapia pituitary. The findings have been confirmed by the control experiments in which preincubating the antiserum with purified sPRL abolished all the immunoreactivity. PRL cells which have been fixed with 4% paraformaldehyde for 2 to 12 hr, do not show any significant difference in antigenicity preservation, but show a better ultrastructure in longer fixation periods. Addition of 2.5% glutaraldehyde to paraformaldehyde could greatly enhance the ultrastructural preservation but concomitantly might cause a loss of 30% of the antigenicity. Post fixation with 1% osmium tetroxide improves the membranous ultrastructure of organelles, however reduced the PRL antigenicity by 50%. The PRL antigenicity (number of protein A-gold binding per PRL granule) in FWadapted tilapia is 1.5 times that in SW-adapted one. Thus, protein A-gold immunocytochemical method is suggested to be suitable for evaluation of the activity of PRL cells in tilapia reared in different environments.View full abstractDownload PDF (9763K) -
KOICHI IIJIMA, MITSURU SATO, NAOSUKE KOJIMA1993 Volume 26 Issue 3 Pages 213-225
Published: 1993
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThe locus ceruleus of Wistar rats was studied to further demonstrate the coexistence of tyrosine hydroxylase (TH) and γ-aminobutyric acid (GABA) in a given neuron. Four sets of serial cryostat sections alternately immunostained for TH-like immunoreactivity (TH-LI) or GABA-LI (240 pairs, 6-μm-thick, Zamboni's fixation) were examined. Statistical analysis performed by Student's t-tests revealed that the difference between numbers of total TH-ergic neurons and total GABA-ergic neurons was not significant, indicating that a single population has both noradrenaline and GABA. The avidin-biotin-peroxidase complex method for glutamic acid decarboxylase (GAD) -LI was applied to rats treated with colchicine (100 μg), 48 hr prior to Zamboni's perfusion. GAD-LI was found in 32% (433/1367) of TH cells in alternate sections for TH-LI or GAD-LI.The low rate of GAD to GABA (433/1321) appears to be due to technical limitations. GAD cells of a similar shape tended to assemble and form small clusters, predominantly in the dorsal division. In situ hybridization using Fluorescin Isothiocyanate for GAD mRNA revealed the signals in a greater number of neurons than GAD-LI cells, but in a significantly fewer number of cells than those showing TH mRNA signals.
The present study proves the presence of GAD in many neurons of the rat locus ceruleus, and provides further evidence for the coexistence of tyrosine hydroxylase and GABA thus supporting our previous conclusion that the locus ceruleus consists of a single population that uses noradrenaline, GABA and serotonin as transmitters.View full abstractDownload PDF (8757K) -
SHASHI WADHWA, GEETA JOTWANI, A. BALASUBRAMANIAM1993 Volume 26 Issue 3 Pages 227-232
Published: 1993
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThe time of appearance and distribution of neuropeptide Y (NPY) in the developing and adult rat heart has been studied by immunohistochemical method using the Avidin biotin technique. At 18 days of gestation and postnatal day 1, no immunoreactivity was detected. Immunoreactivity was first observed on postnatal day 5 around the large blood vessels, developing coronary arteries and very sparsely along the blood vessels in the musculature. At later stages up to adulthood the intensity of immunostaining and density of fibres along the intramyocardial blood vessels increased. After postnatal day 10 the NPY immunoreactive fibres were also seen amongst the muscle fibres. Immunopositive NPY neurons were seen in the ganglionic clusters close to the great vessels at postnatal day 20 and were visualised in between the ventricular muscle bundles near the atrioventricular region only in the adult heart. The ventricular musculature was always more richly innervated than the atria by NPY immunopositive nerve fibres. Thus the present study demonstrates that NPY-like immunoreactivity makes its appearance postnatally, first around the blood vessels and later on the muscle fibres too.View full abstractDownload PDF (6751K) -
NUCLEAR LOCALIZATION OF PARATHYMOSIN IN RAT AND HUMAN HEPATOCYTES. A LIGHT AND ULTRASTRUCTURAL STUDYTOMAS GARCIA-CABALLERO, ELENA ROSON, ROSALIA GALLEGO, MAXIMO FRAGA, FE ...1993 Volume 26 Issue 3 Pages 233-237
Published: 1993
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSParathymosin (ParaT) is an almost ubiquitious peptide first isolated from rat thymus, the highest concentration being in the liver. Its subcellular localization is controversial and both a cytoplasmic and a nuclear distribution have been reported. The aim of the present work was to study the intracellular localization of ParaT in rat and human livers by light immunohistochemistry and immunoelectron microscopy procedures. Both in rat and human livers immunostaining for ParaT was found in the nuclei of hepatocytes, the nucleoli and the cytoplasms being negative. The intensity of immunostaining was variable from cell to cell, but virtually all hepatocytes were positive. No immunoreactivity was found in non-parenchymal cells. Immunogold labelling confirmed these results and showed that ParaT immunoreactivity was associated with both euchromatin and heterochromatin. Our results demonstrate that ParaT is localized in the nucleus of hepatocytes and support the idea that the inactivation of the cytoplasmic enzyme phosphofructokinase-1 is not the unique function of ParaT.View full abstractDownload PDF (2660K) -
KOHSUKE CHIDA1993 Volume 26 Issue 3 Pages 239-244
Published: 1993
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSAlkaline phosphatase (ALP) was purified from the rat kidney. The appropriate enzyme protein was injected subcutaneously into a rabbit as an antigen. The obtained antiserum showed a single precipitin line in the double diffusion test of Ouchterlony. The localization of ALP in the rat liver was examined by means of immunohistochemical techniques. At the light microscopic level, positive reactions were recognized along cell borders between adjacent hepatocytes. On examination with an electron microscope, gold particles were observed only on the surface of microvilli of bile canaliculi by immunogold staining. On the other hand, by the peroxidase-labeled antibody method, reaction products appeared not only on the bile canalicular membrane but also on the sinusoidal and lateral membranes.View full abstractDownload PDF (6319K) -
TOSHIHISA LEE, NOBUKAZU ARAKI, YOICHIRO TAKASHIMA1993 Volume 26 Issue 3 Pages 245-248
Published: 1993
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSDownload PDF (1914K)
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