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Volume 69, Issue 6
June
Displaying 1-22 of 22 articles from this issue
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Anatomy
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Takashi TAKEUCHI, Taketsugu FUJIBUCHI, Yoshinori IMAI, Yoshiaki KAMEI, ...2007 Volume 69 Issue 6 Pages 645-647
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSDifferences in sugar distribution between the villous epithelium and follicle-associated epithelium (FAE) were compared using lectins in the rabbit small intestine. In every portion, villous columnar epithelial cells primarily exhibited a positive reaction to the GalNAc, GlcNAc, galactose, and oligosaccharide. In the ileal Peyer's patch (PP), whereas microvillous epithelial cells exhibited positive reactions, M cells tended to be negative. The villous epithelial reaction to the fucose group was negative, but M cells and microvillous epithelial cells showed a positive to the fucose. No epithelium had a positive reaction to the mannose and glucose. The variety of lectin-binding properties of villous epithelial cells and M cells may reflect specificity for the recognizing luminal substances such as antigenic molecules and bacterial elements.
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Chong-Sup KIM, Phil-Ok KOH, Jae-Hyeon CHO, Oh-Sung PARK, Kyu-Woan CHO, ...2007 Volume 69 Issue 6 Pages 653-655
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSA male deformed Korean native calf was examined macroscopically. The deformed calf had no caudal vertebral columns from 5th lumbar vertebra, sacrum and coccygeal vertebrae. The spinal cord was terminated in the vertebral foramen of the 3rd lumbar vertebra. The cervical vertebrae had scoliosis and the 3rd and 4th cervical vertebrae were fused. The 2nd and 3rd lumbar vertebrae were fused and the left and right transverse processes of the 4th lumbar vertebra articulated with ala of the ilium. The rectum was greatly expanded by the imperforate anus and a rectourethral fistula was formed between the rectum and urethra. The deformed calf was recorded as a first documentation of sacrocaudal agenesis confirmed in a Korean native calf.
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Bacteriology
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Asuka TAKADA-IWAO, Takehiko UTO, Tetsuya MUKAI, Munenori OKADA, Satosh ...2007 Volume 69 Issue 6 Pages 581-586
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSTo facilitate the control of progressive atrophic rhinitis (PAR) of swine caused by toxigenic Pasteurella multocida, an enzyme-linked immunosorbent assay (ELISA) and a serum neutralization test (NT) have recently been developed to detect antibodies against the P. multocida dermonecrotic toxin (PmDNT). However, the NT is a cumbersome and time-consuming technique. To overcome these drawbacks, we developed an indirect ELISA, using recombinant PmDNT expressed in Escherichia coli, for the detection of antibodies to PmDNT in serum samples from pigs. The practical usefulness of this ELISA was compared with the NT using serum samples obtained from experimentally infected and naturally infected pigs. In the pigs experimentally inoculated with vaccine including PmDNT toxoid, the ELISA and neutralization antibodies were detected at almost the same time, and a good correlation was demonstrated between both tests (P<0.01, R2=0.807). Therefore, the ELISA can be used to evaluate the immune reaction of pigs after vaccination with P. multocida toxoid. In a survey conducted on a field herd with a history of clinical AR, the seropositivity by ELISA in pigs of age 4.5-6 months was increased even though the NT was negative, and the correlation was low between the results obtained with the two tests (P<0.01, R2=0.38). Therefore, the results indicated that this ELISA might be a useful alternative to the NT currently used to detect the antibody to PmDNT after vaccination or infection with P. multocida.
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Clinical Pathology
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Expression Patterns of the BRCA1 Splicing Variants in Canine Normal Tissues and Mammary Gland TumorsTakaaki SUGIURA, Satoshi MATSUYAMA, Hideo AKIYOSI, Shigeo TAKENAKA, Jy ...2007 Volume 69 Issue 6 Pages 587-592
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSHuman BRCA1 is familial breast cancer susceptibility gene. Recently, decreased BRCA1 mRNA and protein expression has been identified in sporadic breast tumors. In the reported human BRCA1 splicing variants, delta11b lacks the majority of exon11 and is suspected to have a distinct function in normal tissues. The splicing variants display a variety of expression pattern in breast cancer samples. Although mammary gland tumor is important disease in dog, there are few reports for BRCA1 in the canine tumors. In this study, we examined the relative amounts of BRCA1 splicing variants mRNA in canine normal and mammary tumor samples by RT-PCR to investigate whether there is the altered expression of variant mRNAs in the canine tumor as reported in human. The exon11b-defecting RT-PCR products were observed in all the normal tissues examined and the nucleotide sequence was quite similar to that of human BRCA1 delta11b. In some tumor samples, we did not detect the products targeted for exon10-13 and exon14-15, while these products were observed in all the normal samples examined. Especially, the relative amounts of the exon11-defecting products were remarkably decreased in most of the tumors (11/16).
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Takehiko KAKIZAKI, Nobuyuki HAMADA, Tetsuya SAKASHITA, Seiichi WADA, T ...2007 Volume 69 Issue 6 Pages 605-609
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSAn analysis of ionizing radiation-induced damage in peripheral lymphocytes has been employed to predict the prognosis of radiotherapy in terms of toxicity in normal tissues. Therefore, understanding the sensitivity of lymphocytes to high linear energy transfer (LET)-charged particles would be indispensable for utilizing charged particle therapy in veterinary medicine. However, the availability of such information is very limited. This study aimed to compare the radiosensitivity of feline T lymphocytes to γ-rays (0.2 keV/μm) and 4 different types of charged particles with LET values ranging from 2.8 to 114 keV/μm. It was observed that the relative biological effectiveness, inactivation cross-section, and isodose-induced apoptosis increased in an LET-dependent manner. On the other hand, no difference in apoptosis frequency was observed in the cells exposed to an isosurvival dose of all the radiation types tested. This is the first study that demonstrates the LET dependence of cell killing and apoptosis induction in feline T lymphocytes. Our results suggest that lymphocytes can be effectively used to predict the prognosis of charged-particle therapy in cat patients.
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Takaki WARITANI, Masaaki ONDA, Yoko OKUNO, Sakurako NEO, Mitsuru FURUI ...2007 Volume 69 Issue 6 Pages 669-671
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSWe developed a one-step immunochromatography assay kit to measure high levels of canine trypsin-like immunoreactivity (cTLI) for bedside estimation of canine pancreatitis. The serum cTLI level can be determined within 10 min by visual comparison of color strengths in the test and reference zones. The serum cTLI levels determined by this method correlate well with canine TLI-ELISA and can be classified into 3 categories: cTLI levels higher than 60 ng/ml were considered positive; 20-60 ng/ml, weakly positive; and less than 20 ng/ml, negative. Twelve dogs suspected of pancreatitis were examined using this method; 4 dogs were positive, 2 were weakly positive, and 6 were negative. This test can detect a high level of serum cTLI and a positive result in the TLIH test will provide critical information for evaluation of pancreatitis in dogs.
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Ethology
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Katumasa OOKAWA, Kazuo MOCHIZUKI, Eiji SHIDA, Toshihiro SUZUKI, Toshih ...2007 Volume 69 Issue 6 Pages 593-598
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSIn our previous experiments with rats, ovary lipid from Skipjack Tuna (Katsuwonus pelamis) (OLS) was shown to have a mitigating effect on anxiety and/or fear in elevated T-maze tests. This suggests that OLS has some effect on the central nervous system (CNS) of rats. Thus, we performed experiments to examine the status of CNS in rats given OLS. The effect of OLS on chronic stress was also examined at the same time. The feed for control rats used oil and fat that have the same energy percentages for n-6 and n-3 fatty acids and the same n-6/n-3 ratio as OLS. As a result, rats given OLS for 28 days had lower serotonin levels in various brain areas regardless of stress application, showing that OLS affected the serotonin nervous system. From this, it was inferred that the ability of OLS to mitigate anxiety and/or fear resulted from its action on CNS, especially the serotonin nervous system. Substances other than the essential fatty acids may have been responsible for the action of OLS on monoamines and the metabolites. The effect of OLS on CNS, especially the serotonin nervous system, suggests that OLS may suppress anxiety.
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Katumasa OOKAWA, Kazuo MOCHIZUKI, Eiji SHIDA, Toshihiro SUZUKI, Toshih ...2007 Volume 69 Issue 6 Pages 633-636
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSUsing an elevated plus-maze test, we evaluated anxiety level in rats given ovary lipid extracted from Skipjack tuna (Katsuwonus pelamis; OLS). The percentage of open time was significantly higher in rats given OLS than in rats in the control group, but lower than in rats given diazepam (1.0 mg/kg body weight). Based on this fact and findings about other indicators, this study showed that OLS does not have as fast-acting and strong an anti-anxiety effect as diazepam but that continuous ingestion of OLS causes an anti-anxiety effect in animals.
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Internal Medicine
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Tomoko TAKAHASHI, Isao OTANI, Masaru OKUDA, Masashi INOUE, Kanako ITO, ...2007 Volume 69 Issue 6 Pages 677-681
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSAn 8-year-old spayed female Golden Retriever was referred to us for evaluation of mild lymphocytosis. The peripheral lymphocytes were comprised of mostly large granular lymphocytes (LGLs), and flow cytometry showed that they were mostly CD3+8+ T lymphocytes. Clonal rearrangement of the T-cell receptor gene was identified in the peripheral blood, and the dog was therefore diagnosed with LGL chronic leukemia. The dog was subclinical without treatment until hospitalization on day 154, at which point the lymphocytes looked like lymphoblasts and the surface markers changed to CD3-8-. This was regarded as malignant transformation from LGL chronic leukemia to the acute type. Sequential chemotherapy was started, but the dog died on day 190. Necropsy revealed tumor cell infiltration into the heart, skin, and brain.
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Parasitology
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Hisashi INOKUMA, Misato OHASHI, JILINTAI, Shigeyuki TANABE, Kazuro MI ...2007 Volume 69 Issue 6 Pages 661-664
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSDNA from 111 ticks collected by flagging in Tokachi district, Eastern Hokkaido, Japan were examined for infection with Rickettsia and Ehrlichia, by PCR and sequencing methodology. For Rickettsia, analysis of the partial sequence of the citrate synthase gene was successfully performed on 11 DNA samples from I. persulcatus, and 7 of them showed 99.8% identical with Rickettsia helvetica while the other 4 showed 99.8% identical with `Candidatus Rickettsia tarasevichiae'. For Ehrlichia, a partial sequence of the 16S rRNA gene detected from I. persulcatus was 100% identical with that from Ehrlichia muris, and another DNA sample from I. ovatus showed 99.8% identical with Ehrlichia species detected from I. ovatus. The results suggest that the pathogens detected here might be distributed in this area.
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Pathology
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Masayuki NOMURA, Yoshinao HOSAKA, Yoshinori KASASHIMA, Hiromi UEDA, Ka ...2007 Volume 69 Issue 6 Pages 637-639
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSThe DNA microarray analysis for matrix metalloproteinase (MMP)-related mRNA expression in equine superficial digital flexor tendinitis indicated that mRNA level of MMP-13 was apparently up-regulated in the tendinitis as compared to normal tendon. In situ hybridization also revealed that fibroblastic cells proliferated in the granulation tissue generated in the tendinitis actively expressed MMP-13 mRNA. On the other hand, in normal tendon, a few fibroblastic cells and vascular components lied in the endotenon barely expressed its mRNA, but other cellular components in the tendon bundle were not positively hybridized. As mentioned above, MMP-13 but not other collagenases or gelatinases, may play an important role in tendon injuries in the racehorses.
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Takuya HIRAI, Tetsuo NUNOYA, Ryozo AZUMA2007 Volume 69 Issue 6 Pages 641-643
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSA goat with neurologic signs had multifocal abscesses containing sulfur granules in the right brain and temporal bone. Histologically, the lesions consisted of pyogranulomas with several radiating bacterial colonies of various sizes. A tangled mass of filamentous and gram-positive bacteria was recognized in the central part of the colony. Actinomyces naeslundii antigen was detected in the colonies of bacteria in the brain and neighboring bone tissue by immunohistochemistry. Actinomycosis involving the central nervous system (CNS) and temporal bone is rare in animals. Cerebral infection with A. naeslundii may have resulted from direct extension from cervicofacial regions because the CNS lesions were distributed asymmetrically and were continuous with the right temporal bone.
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Yukio M. SEIMIYA, Maki TAKAHASHI, Takashi KUDO, Koji SASAKI2007 Volume 69 Issue 6 Pages 657-660
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSPathological and bacteriological examinations were carried out on a neonatal calf that had developed nervous symptoms such as opisthotonus and blindness since it was born one month prior to full term. The principal lesions were characterized by fibrinopurulent inflammation of the meninges, choroid plexuses, and ventricular walls with limited extension to the subependymal parenchyma in the spinal cord. Purulent inflammation was also found in several visceral organs and tissues. Streptococcus pluranimalium was isolated from the brain and cerebrospinal fluid. These results suggest that the animal suffered from meningoventriculitis with septicemic S. pluranimalium infection.
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Hiroko HIRAOKA, Masaharu HISASUE, Naho NAGASHIMA, Takako MIYAMA, Takas ...2007 Volume 69 Issue 6 Pages 665-668
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSAn eleven-year-old female pug was referred to Yamaguchi University Animal Hospital for evaluation of anemia and thrombocytopenia. The cytological examination of the peripheral blood showed some giant monocytic lineage blast cells. A few granulocytes and platelets had dysplastic features. On day 7, in addition to increasing the monocytic lineage cells, the dysplastic features of the blood had also increased compared to the initial examination. We performed bone marrow aspiration upon her death. The bone marrow revealed dysplastic features in all three hematopoietic cell lines, and an increase in the monocytic cell line. Based on the features of the bone marrow and the peripheral blood, this case was confirmed to be myelodysplastic syndrome-Chronic myelomonocytic leukaemia (MDS-CMML).
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Physiology
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Yumiko SHIMOYAMA, Doaa KIRAT, Yuko AKIHARA, Kazufumi KAWASAKO, Misa KO ...2007 Volume 69 Issue 6 Pages 599-604
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSIn this study, the expression and distribution of monocarboxyolate transporter 1 (MCT1) along the intestines (duodenum, jejunum, ileum, cecum, colon and rectum) of dogs were investigated at both the mRNA and protein levels. The expression of MCT1 protein and its distribution were confirmed by Western blotting and immunohistochemical staining using the antibody for MCT1. We identified mRNA coding for MCT1 and a 43-kDa band of MCT1 protein in all regions from the duodenum to the rectum. Immunoreactive staining for MCT1 was also observed in epithelial cells throughout the intestines. MCT1 immunoreactivity was greater in the large intestine than in the small intestine. MCT1 protein was predominantly expressed on the basolateral membranes along intestinal epithelial cells, suggesting that MCT1 may play an important role in lactate efflux and transport of short-chain fatty acids (SCFAs) to the bloodstream across the basolateral membranes of the dog intestine.
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Public Health
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Randy LAPUZ, Hiroyuki TANI, Kazumi SASAI, Kazutoshi SHIROTA, Hiromitsu ...2007 Volume 69 Issue 6 Pages 649-652
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSIn order to determine the epidemiological link between the Salmonella Enteritidis contamination in a rat-infested chicken layer farm, an attached egg processing facility and liquid egg samples, several S. Enteritidis isolates were analyzed by pulsed-field gel electrophoresis (PFGE) and bacteriophage typing. A total of 33 S. Enteritidis strains were isolated from a total of 4,081 samples. Similar pulsed-field patterns were generated by S. Enteritidis isolates from liquid eggs, rats and effluent water. Additionally, only two phage types were detected among the S. Enteritidis isolates, PT 1b and PT 6. These results suggest that S. Enteritidis isolates from rats, egg processing facility, and liquid eggs are genetically related. Furthermore, S. Enteritidis infection in rats in layer farms poses a serious public health concern and should be included in future epidemiological studies.
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Takehisa YAMAMOTO, Toshiyuki TSUTSUI, Akiko NISHIGUCHI, Sota KOBAYASHI ...2007 Volume 69 Issue 6 Pages 673-675
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSIn June 2005, an outbreak of avian influenza (AI) caused by a low pathogenic H5N2 virus was identified in Japan. A serological surveillance was conducted because the infected chickens did not show any clinical signs. The Markov Chain Monte Carlo Method was used to evaluate the performances of serological HI and AGP tests because there was not enough time when the surveillance was initiated to conduct a test evaluation. The sensitivity of the AGP test (0.67) was lower than that of the HI test (0.99), while the specificities were high for both tests (0.96 for AGP and 0.90 for HI). Based on the low sensitivity of the AGP test, the HI test was used for primary screening in later stages of the epidemic.
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Surgery
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Kazuaki YAMAZOE, Shuji MIYAMOTO, Yoko HIKOSAKA, Koji KITAGAWA, Kazuhir ...2007 Volume 69 Issue 6 Pages 611-617
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSA pad equivalent for a dog was prepared as a substitute for the loss of footpad. In addition to the time course of formation on epidermal morphogenesis, we investigated expressions of α6 integrin subunit as adhesive molecule, and laminin and type IV and VII collagens as extracellular matrices of basement membrane components. Epithelium of the pad equivalent was thick enough to be easily confirmed at 5 days at the air-liquid interface, but many creases appeared on it at 7 days, and it shrank at 10 and 14 days. Keratinocytes were increased in 4 to 5 cell layers at 1 day at the air-liquid interface, differentiating into basal cell layer. Granular and corneal cell layers were confirmed until 5 days, and maintained their shape at least until 14 days. Alpha 6 integrin was expressed at almost the same fluorescent intensity as native pad tissue at 1 day at the dermal-epidermal junction. Laminin and type IV collagen were intermittently expressed at 5 and 10 days, respectively, at the dermal-epidermal junction, and at 14 days the fluorescence showed almost the same intensity as native pad tissue. The expression of type VII collagen was discontinuous at 2 days at the dermal-epidermal junction, but remained as it was at 14 days. The present findings suggested that although the formation of anchoring fibrils in basement membrane was incomplete, the pad equivalent in the dog was reconstructed similar to a native pad by epidermal morphogenesis.
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Midori OKADA, Masato KITAGAWA, Hisashi SHIBUYA, Kiichi KANAYAMA, Tsune ...2007 Volume 69 Issue 6 Pages 683-686
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSA 10-year-old female mongrel cat with back pain was brought to the Nihon University Animal Medical Center. Palpation demonstrated a mass in the back region. Radiography revealed partial destruction of the processus spinosus and the arch of the T8 and T9 vertebrae. On magnetic resonance imaging, the mass was found to have compressed the spinal cord and extended to the outside of the spinal canal. We performed extirpation of the mass, and confirmed that it arose from the spinal canal. Histopathologically, the mass was a malignant peripheral nerve sheath tumor.
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Michio FUJITA, Yumi TAKAISHI, Hideyuki NAGAE, Naoyuki WATANABE, Daisuk ...2007 Volume 69 Issue 6 Pages 687-690
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSMagnetic resonance (MR) and computed tomography (CT) were performed in an 8-year-old, spayed female cat with chronic effort respiration at the inspiration phase and stertor. Increased bone opacity in the areas of the head, neck and thorax were observed on radiography. MR images showed no signal intensity on both transverse T1WI and T2WI of the nasal cavity. CT revealed increased bone density and hypertrophy of the nasal turbinate and a narrowed nasal passage. From these results, we concluded this case had osteopetrosis-like disease, and that the respiratory distress was caused by hypertrophy of the nasal turbinate.
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Theriogenology
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Min Kyu KIM, Mohammad Shamim HOSSEIN, Hyun Ju OH, Heru Yuda FIBRIANTO, ...2007 Volume 69 Issue 6 Pages 627-632
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSGlutathione (GSH) concentrations of oocytes are considered as an important marker of the cytoplasmic maturation. The present study was designed to compare GSH concentrations of in vivo and in vitro matured canine oocytes. In vivo matured oocytes were collected 72 hr after ovulation by flushing fallopian tubes after laparotomy. Ovaries were collected from bitches with different reproductive stages, and collected oocytes were divided into 2 groups according to the size viz. < 120 μm and > 120 μm in diameter and cultured for 72 hr in Tissue Culture Medium-199 supplemented with 10% FBS, 2.2 mg/ml sodium bicarbonate, 2.0 μg/ml estrogen, 0.5 μg/ml FSH, 0.03 IU/ml hCG, and 1% penicillin-streptomycin solution in the presence or absence of 50 μM β-mercaptoethanol. GSH concentrations were determined by the dithionitrobenzoic acid-glutathione disulfide (DTNB-GSSG) reductase recycling assay. GSH concentrations of immature canine oocytes were 2.9 and 3.8, 3.5 and 6.8, and 3.1 and 6.5 pM/oocyte for < 120 μm and > 120 μm in diameter oocyte groups at anestrous, follicular and luteal stage, respectively (P<0.05). In vivo matured oocytes had significantly higher GSH concentrations compared with in vitro matured oocytes. The GSH content was 19.2 pM/oocyte for in vivo matured oocytes, while 4.1 to 8.1 and 5.7 to 13.2 pM/oocyte for in vitro matured oocytes cultured in the absence or presence of β-mercaptoethanol, respectively (P<0.05). Presence of β-mercaptoethanol increased GSH synthesis in canine oocytes cultured in vitro, and oocytes collected from follicular and luteal stage was superior to anestrus oocytes.
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Toxicology
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Kenji OHYAMA, Masanori OHTA, Tomoaki SANO, Kazumasa SATO, Yoshiko NAKA ...2007 Volume 69 Issue 6 Pages 619-625
Published: 2007
Released on J-STAGE: July 05, 2007
JOURNAL FREE ACCESSWe have analyzed the effects of low-dose transplacental and lactational exposure of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on gene expression relating to the dioxin and sexual hormone cascade, and demonstrated the effects on testicular growth and sexual maturation in male offspring rats. TCDD (10 ng/kg) was administered to dams on Days 7 and 14 of gestation, and on Days 0, 7 and 14 after delivery. Gene expression of cytochrome P450 family 1 subfamily A polypeptide 1 (CYP1A1) in the liver of 17-day-old rats was significantly increased compared with controls. Furthermore, expression of estrogen receptors (ER)α and ERβ was significantly increased at 17 and 42 days old, respectively in the testis of TCDD-administered rats compared with controls. Although testicular weight and the seminiferous tubule diameter were increased in 17-day-old rats, there was no difference in the number of germ cells between TCDD-treated and control animals. The expressions of androgen receptor and inhibin subunit genes were not significantly changed. These findings suggest that low-dose exposure of TCDD leads to unusual development of the testis by perturbation of steroid hormone homeostasis.
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