The Tohoku Journal of Experimental Medicine
Online ISSN : 1349-3329
Print ISSN : 0040-8727
ISSN-L : 0040-8727
Volume 175, Issue 1
Displaying 1-6 of 6 articles from this issue
  • YOSHIHIRO INOUE, TAKAYOSHI TODA, TAKEHIRO IGAWA, TAKESHI TANI, YUKIO K ...
    1995 Volume 175 Issue 1 Pages 1-13
    Published: 1995
    Released on J-STAGE: August 31, 2006
    JOURNAL FREE ACCESS
    INOUE, Y., TODA, T., IGAWA, T., TANI, T. and KIMURA, Y. The Response of Serum and Hepatic Lipids and the Aortic Wall to Different Levels of Dietary Cholesterol: A Comparative Study between Hyperlipidemia-and- Atherosclerosis-Prone Quail and Commercially Available Quail. Tohoku J. Exp. Med., 1995, 175 (1), 1-13-A hyperlipidemia-and-atherosclerosis-prone (LAP) quail model was developed by dietary cholesterol feeding through genetic selection of commercially available (CA) Japanese quail. The response of serum lipids and the aortic wall to dietary cholesterol feeding was compared in CA and LAP quails. Ten groups were fed a combination diet with different levels of cholesterol and corn oil for 12 weeks. In CA quail, dietary feeding of cholesterol only failed to induce significant hypercholesterolemia or atherosclerotic lesion. The respective optimal dietary levels of cholesterol and corn oil to induce hyperlipidemia and atherosclerotic lesion, were 2% and 15%, respectively. Ad-libitum feeding of only 0.5% cholesterol without corn oil induced significant hypercholesterolemia and aortic atherosclerosis in LAP quail. The main proliferating cellular component of the aortic atherosclerotic lesion was phenotypically transformed fibroblasts from medial fibroblasts. These results suggest that the LAP quail is a useful animal model for the study of atherosclerosis.
    Download PDF (2972K)
  • HIDEO INABA, MASAHIKO ARAKI, SHINPEI KON, MIE IMAI, TADANOBU MIZUGUCHI
    1995 Volume 175 Issue 1 Pages 15-28
    Published: 1995
    Released on J-STAGE: August 31, 2006
    JOURNAL FREE ACCESS
    INABA, H., ARAKI, M., KON, S., IMAI, M. and MIZUGUCHI, T. Modulation of Protein Kinase C Produces Glucose-Dependent Alterations in Hemodynamics and Metabolism in the Perfused Liver in Fasted Rats. Tohoku J. Exp. Med., 1995, 175 (1), 15-28-Protein kinase C (PKC) has been suggested to be involved in the regulation of hepatic blood flow and metabolism. To confirm the role of PKC, we studied the effects of active and inactive PKC modulators on hemodynamics and metabolism in the perfused rat liver. In addition, the influence of glucose concentration in the medium was studied. The liver was isolated from fasted Sprague-Dawley rats and perfused through the portal vein at a constant pressure of 12cm H2O. 4α-Phorbol 12, 13-didecanoate, an inactive phorbol ester for PKC, slightly decreased hepatic flow only when its initial concentration was raised to 20μM. In contrast, 4β-phorbol 12, 13-didecanoate, an active phorbol ester for PKC, at initial concentrations of 80nM to 1.28μM decreased hepatic flow and oxygen consumption in a dose-dependent manner, and increased lactate production. HA-1004, a relatively inactive PKC inhibitor, at an initial concentration of 33μM did not modify the effects of phorbol 12-myristate 13-acetate (PMA), a potent PKC activator. However, H-7, a relatively specific PKC inhibitor, at a concentration of 33μM attenuated the effects of PMA. The effects of PMA were enhanced by an increase in D-glucose concentration from 10 to 25mM but not by an increase in L-glucose concentration. These results suggest that modulation of PKC exerts glucose-dependent influences on hepatic flow and metabolism.
    Download PDF (1330K)
  • SATOSHI AKAISHI, MASAO KOBARI, KAZUNORI TAKEDA, SEIKI MATSUNO
    1995 Volume 175 Issue 1 Pages 29-42
    Published: 1995
    Released on J-STAGE: August 31, 2006
    JOURNAL FREE ACCESS
    AKAISHI, S., KOBARI, M., TAKEDA, K. and MATSUNO, S. Targeting Chemotherapy Using Antibody-Combined Liposome against Human Pancreatic Cell-Line. Tohoku J. Exp. Med., 1995, 175 (1), 29-42-Anti-tumor effect of Adriamycin (ADM)-encapsulated and CA19-9 antibody-conjugated artificial lipid membrane follicle liposomes against a human pancreatic cancer cell-line PK-1 was studied in vitro and in vivo. The liposome compound (lipo c ADM=Ab) showed a stronger cell damage than ADM-encapsulated liposome (lipo c ADM) and free ADM, especially when the contact time was short and the concentration was low. The intra-tumor concentration of ADM in the group of i.v. injection of lipo c ADM=Ab showed the highest value, over twice those of lipo c ADM and free ADM after 120hr. Lipo c ADM=Ab showed a significant inhibitory effect on the tumor growth inhibition test in vivo, and the final tumor weight at the 19th day was 27% in the group of lipo c ADM=Ab and 52% in the group of free ADM as compared with the control. The targeting chemotherapy using liposomes was demonstrated to have a stronger anti-tumor effect than the administration of anti-cancer drug alone owing to enhanced tumor accessibilty and good targeting.
    Download PDF (2051K)
  • TETSUYA ITO, NARUJI SUGIYAMA, MASANORI KOBAYASHI, KIYOSHI KIDOUCHI, TA ...
    1995 Volume 175 Issue 1 Pages 43-53
    Published: 1995
    Released on J-STAGE: August 31, 2006
    JOURNAL FREE ACCESS
    ITO, T., SUGIYAMA, N., KOBAYASHI, M., KIDOUCHI, K., ITOH, T., UEMURA, O., SUGIYAMA, K. and TOGARI, H. Alteration of Ammonia and Carnitine Levels in Short-Term Treatment with Pivalic Acid-Containing Prodrug. Tohoku J. Exp. Med., 1995, 175 (1), 43-53-We investigated the influence on mitochondrial functions in carnitine deficiency caused by short-term treatment of cefteram-pivoxil (CFTM-PI) which is one of pivaloyloxymethyl-esterified antibiotics in adult volunteers and diseased children. Administration of CFTM-PI caused hypocarnitinemia in all cases, and we observed a significant elevation of blood ammonia levels compared with those after its withdrawal in diseased children. A significant negative correlation was found between the levels of serum free carnitine and blood ammonia, and a positive correlation was observed between serum carnitine and blood glutamine levels in all adult samples and samples during administration in diseased children. Our data suggest that these antibiotic medications affect the mitochondrial function even in a short-term treatment and that L-carnitine supplementation would be necessary for patients treated with CFTM-PI.
    Download PDF (978K)
  • MOMOYO ISHIKAWA, TAKAHIRO FUJINO, HITOSHI SAKASHITA, KOSUKE MORIKAWA, ...
    1995 Volume 175 Issue 1 Pages 55-67
    Published: 1995
    Released on J-STAGE: August 31, 2006
    JOURNAL FREE ACCESS
    ISHIKAWA, M., FUJINO, T., SAKASHITA, H., MORIKAWA, K. and YAMAMOTO, T. Kinetic Properties and Structural Characterization of Highly Purified Acetyl-CoA Synthetase from Bovine Heart and Tissue Distribution of the Enzyme in Rat Tissues. Tohoku J. Exp. Med., 1995, 175 (1), 55-67-Acetyl-CoA synthetase from bovine heart has been purified to homogeneity and been crystallized. The purification procedure involves ammonium sulfate precipitation and subsequent column chromatography on DEAE-Sepharose, Blue-Sepharose, CoA-Agarose and Superose 6. The purified enzyme has a specific activity of 45units/mg protein, and its molecular weight estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis is approximately 72, 000. The purified enzyme specifically utilizes acetate, ATP and CoA. Apparent Km values of the purified enzyme for acetate, CoA, and ATP were 0.16mM, 0.14mM and 0.25mM, respectively. Limited digestion with trypsin, subtilisin BPN' and chymotrypsin revealed that the enzyme contains a 56k segment resistant to these proteases. Secondary structure contents of the purified enzyme and the 56k Cryptic fragment were analyzed by circular dichroism measurement. The intact molecule contains 30% α-helix and 30% β-structure, and trypsin digests α-helix rich regions more substantially. Western blot analysis of rat tissue homogenates by specific antibodies against the purified enzyme indicated that the 72k enzyme is present in a wide variety of tissues and is most abundant in heart and kidney.
    Download PDF (2685K)
  • KIKUYA TAKASE, MOTOHARU ISHIKAWA, HIROSHI HOSHIAI
    1995 Volume 175 Issue 1 Pages 69-76
    Published: 1995
    Released on J-STAGE: August 31, 2006
    JOURNAL FREE ACCESS
    TAKASE, K., ISHIKAWA, M. and HOSHIAI, H. Apoptosis in the Degeneration Process of Unfertilized Mouse Ova. Tohoku J. Exp. Med., 1995, 175 (1), 69-76 -In mammals, ova which are not fertilized undergo degeneration. Thus, it seems that the ovum is programmed to die unless fertilization and embryogenesis occur, but little is known about the mechanism of such degeneration. To investigate this process, we observed the morphological changes of cultured unfertilized ova and stained DNA fragmentation by the modified TUNEL method (treating floating samples in liquid reagents) to detect apoptosis. Ova were collected from the oviducts of superovulated mice and cultured for observation. The number of morphologically abnormal ova with shrinkage of the ooplasm and cytoplasmic fragmentation, which are typical features of apoptosis, showed a significant gradual increase from 24 to 32hr (p<0.05) and an abrupt increase from 40hr of incubation (p<0.001). DNA fragmentation, which is one of the biological changes seen in apoptosis, was observed in the ooplasm of both intact and abnormal ova, cells with cytoplasmic fragmentation, and in the first polar body at the time of ovum collection as well as after incubation. These findings demonstrate that apoptosis is related to the process of degeneration in the mouse ovum and first polar body.
    Download PDF (2138K)
feedback
Top