Purification and characterization of feline ghrelin and its possible role     

Ida T  Miyazato M  Naganobu K  Nakahara K  Sato M  Lin XZ  Kaiya H  Doi K  Noda S  Kubo A  Murakami N  Kangawa K 《Domestic animal endocrinology》2007,32(2):93-105

Ghrelin, a novel 28-amino acid peptide with an n-octanoyl modification at Ser3, has been isolated from rat and human stomach as an endogenous ligand for the growth hormone secretagogue receptor. Here, we purified feline ghrelin and examined its possible physiological role in cats. The major active form of feline ghrelin is a 28-amino acid peptide octanoylated (C8:0) at Ser3; except for one amino acid residue replacement, this structure is identical to those of rat and human ghrelins. However, much structural divergence in peptide length and fatty acid modification was observed in feline ghrelin: peptides consisting of 27 or 26 amino acids lacking Gln14 and/or Arg28 were found, and the third serine residue was modified by octanoic acid (C8:0), decanoic acid (10:0), or unsaturated fatty acids (C8:1, C10:1 and C10:2). In agreement with the structural divergence, two kinds of cDNA with different lengths were isolated. Administration of synthetic rat ghrelin increased plasma growth hormone levels in cats, with a potency similar to that in rat or human. Plasma levels of ghrelin in cats increased approximately 2.5-fold after fasting. The present study indicates the existence of structural divergence in feline ghrelin and suggests that, as in other animals, ghrelin may play important roles in GH release and feeding in cats.  相似文献   

Hemorrhagic necrotizing splenitis in a slaughter pig infected with Arcanobacterium species     

Ohba T  Shibahara T  Kobayashi H  Kubo M  Takashima A  Imai S  Murakami S  Kadota K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(4):449-453

A 6-month-old barrow presented with lethargy, inappetence and dysstasia. At necropsy, multiple coalescing hemorrhagic foci were detected in the margins of the spleen. Gram-positive bacilli were isolated from the spleen, kidney, muscle and liver. Comparative 16S rDNA gene sequencing analysis of the isolates (TO16177) revealed that they would be the same species of unpublished Arcanobacterium species strain HJ57-14E (accession no. gi 18873551) (99.7% similarity based on a comparison of 675 bp). Histologic examination of the splenic tissue sections revealed extensive necrosis and inflammation, and gram-positive bacilli were discernible. Multifocal necrosis was also detected in the liver. Immunohistochemically, the isolates were cross-reacted with polyclonal antibodies against Arcanobacterium pyogenes and Actinomyces naeslundii, and the reaction was strong for the latter. Similar reactions were found in the suppurative lesions of the tonsil, and occasionally in the spleen and lymph nodes. The present results indicate that the unpublished Arcanobacterium species induced multiple organ failure accompanied by acute hemorrhagic necrotizing splenitis in this growing-finishing pig.  相似文献   

Diffuse bilateral hemangiosarcoma of the uterus in a dog     

Murakami Y  Uchida K  Yamaguchi R  Tateyama S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(2):191-193

A 15-year-old female mongrel dog showed abdominal swelling, marked hemorrhagic ascites and vulvar discharge, and ovariohysterectomy was performed. Grossly, the uterus was enlarged bilaterally without apparent mass formation. Histologically, the uterine muscular wall was composed of proliferated sinusoidal vessels. In some areas, irregular and small vessels proliferated markedly, while in others, pleomorphic and atypical tumor cells forming irregular vascular structures were predominant. From these findings, the case was diagnosed as diffuse bilateral hemangiosarcoma of the uterus that invaded to the ovary and broad ligament. The relationship between the tumor and angiomatosis was discussed.  相似文献   

Perineal Nets of Proteoglycans and Glycoproteins in Albino Rat Hippocampus     

W. Mubarak    M. N. Saleh    R. Sayed    A. Ohtsuka    T. Taguchi    T. Murakami 《Anatomia, histologia, embryologia》2005,34(S1):34-35

Perineuronal nets (PNs) of condensed extracellular matrix (ECM) have been shown to characterize the microenvironment of individual neurons and the chemoarchitecture of some brain regions. In the present study, PNs in the hippocampus were visualized with a cationic iron colloid method for sulphated proteoglycan content and a plant lectin from Vicia villosa agglutinin (VVA) for N-acetylgalactosamine containing glycoconjugates. The ECM molecules were organized in reticular coats (PNs) around non-pyramidal cells in the Ammons horn (Corneu Ammons, CA) and subicular region, in addition to pyramidal neurons located in CA2 and CA3 regions. CA2 stratum pyramidale exhibited the most intense staining of its PNs and a diffuse intervening neutrophil labelling, while CA3 region showed a graded fashion of staining intensity. The subiculum displayed intensely stained perineuronal coats. Notably, the hippocampal perineuronal nets revealed overlapped staining characteristics with both staining methods. However, cell coats of the subicular neurons showed various degrees of labelling characteristics with both markers. It is suggested that the PNs in the hippocampus are correlated with the fast spiking inhibitory GABAergic neurons and their target pyramidal cells, and this is important to keep the excitatory elements under control and therefore control the information processes within the hippocampus.  相似文献   

Development of Cat Embryos Produced by Intracytoplasmic Injection of Spermatozoa Stored in Alcohol     

M Murakami  NWK Karja  P Wongsrikeao  B Agung  M Taniguchi  H Naoi  T Otoi 《Reproduction in domestic animals》2005,40(6):511-515

This study was conducted to examine whether cat spermatozoa stored in ethanol for 1 month was capable of developing into pronuclei and of supporting normal embryonic development. In vitro matured oocytes were injected with frozen-thawed spermatozoa and ethanol-stored spermatozoa. The status of oocytes and sperm nuclei was examined at 4 and 18 h after injection of spermatozoa, and the presumptive zygotes were cultured for 7 days to assess the development of oocytes injected with each storage sperm. The percentage of enlarged sperm head at 4 h after injection was higher in ethanol-stored spermatozoa than in frozen-thawed spermatozoa, but there was no significant difference in the development of oocytes and sperm nuclei at 18 h after injection between the two groups. The development of oocytes to the blastocyst stage after injection of spermatozoa was observed only in oocytes with frozen-thawed spermatozoa. Of oocytes injected with ethanol-stored spermatozoa, two (2.8%) oocytes developed to the 16-cell stage. These results indicate that cat spermatozoa stored in ethanol can decondense and form male pronuclei after intracytoplasmic injection. However, the oocytes injected with ethanol-stored spermatozoa did not have the ability to develop to the blastocyst stage.  相似文献   

Three dogs under 2 years of age with heartworm caval syndrome     

Hidaka Y  Hagio M  Murakami T  Okano S  Natsuhori K  Narita N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(10):1147-1149

Heartworm caval syndrome (CS) occurred in three dogs under 2 years of age. A 23-month-old dog was recovered by surgical and medical treatments, but the other 2 dogs (15 and 21 months old) died. Necropsy demonstrated 12 heartworms in the 15-month-old dog and 8 worms in the 21-month-old dog. Histopathologically, pulmonary arterial embolism caused by dead worms and thrombi were observed in these cases. The findings suggested that CS could develop regardless of canine age and worm burden if pulmonary arterial embolism related to worm death or thrombus formation were induced.  相似文献   

Phylogenetic Analysis of Field Isolates of Feline Calcivirus (FCV) in Japan by Sequencing Part of Its Capsid Gene     

Sato Y  Ohe K  Murakami M  Fukuyama M  Furuhata K  Kishikawa S  Suzuki Y  Kiuchi A  Hara M  Ishikawa Y  Taneno A 《Veterinary research communications》2002,26(3):205-219

The molecular epidemiology of the infectious disease caused by feline calcivirus (FCV) in Japan was investigated by analysing the phylogenetic relationship among 21 Japanese field isolates, including the F4 strain, and 30 global isolates. Parts of the capsid gene (B–F) of the isolates were amplified by RT-PCR, and the amino acid sequences were compared with those from the global isolates. Thirty-seven and 14 out of a total of 51 isolates were clustered into two distinct genogroups, I and II respectively, by UPGMA and NJ analysis. Seven of the 21 Japanese isolates (33%) fell into group I together with 30 global isolates, while the other 14 Japanese isolates (67%) belonged to group II. The bootstrap repetition analysis of groups I and II formed by the NJ method gave a value of 99.0%. The 14 latter Japanese isolates were clearly separated from the isolates in group I, and they were different from any previously known FCV, forming a new genogroup, which implies that this lineage has been confined to Japan. Comparing the amino acid sequences shared by groups I and II, the amino acid at position 377 in B region was asparagine (Asn or Asp (NH₂)) in group I, while it was lysine (Lys) in all the strains in group II. Similarly, the amino acid at position 539 in the F region was alanine (Ala) or proline (Pro) in group I, while it was valine (Val) in group II; glycine (Gly) at position 557 in group I was serine (Ser) in Group II; and phenylalanine (Phe) or leucine (Leu) at position 566 in genogroup I was tyrosine (Tyr) in group II.  相似文献   

Age- and sex-related changes in susceptibility of Wistar rats to Strongyloides venezuelensis infection     

Rivero JC  Inoue Y  Murakami N  Horii Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(6):519-521

The effects of host age and sex on susceptibility to Strongyloides venezuelensis in Wistar rats were examined by counting larvae recovered from the lungs of animals 3 days after infection. The susceptibility of female rats to S. venezuelensis rapidly decreased with age and elevated estrogen. Resistance in female rats inoculated at 6 and 10 weeks of age was nine and twenty-fold higher, respectively than that in the youngest group (3 weeks). In contrast, the susceptibility of male animals was lowest in the youngest group, then increased with age and elevated testosterone. Sex differences in susceptibility were not evident in the youngest group, but became apparent with age.  相似文献   

Androgen- and estrogen-dependent sex differences in host resistance to Strongyloides venezuelensis infection in Wistar rats     

Rivero JC  Inoue Y  Murakami N  Horii Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(6):457-461

The effects of male and female sex hormones on the protective capacity of Wistar rats against infection with Strongyloides venezuelensis were investigated. Male rats were more susceptible than females in terms of worm recovery from the lungs. Orchidectomy of male animals significantly reduced the plasma testosterone concentration and increased host resistance to the migratory stages of S. venezuelensis larvae. In contrast, ovariectomy of female animals significantly decreased host resistance in association with a significant reduction of estrogen levels. To examine the direct effect of sex hormones, exogenous testosterone and estrogen were implanted into animals. Susceptibility significantly increased or decreased in ovariectomized females given testosterone or estrogen, respectively. These results suggest that male and female sex hormones are important in the down- and up-regulation of host resistance against S. venezuelensis in Wistar rats.  相似文献   

Involvement of CD28/CTLA4-B7 costimulatory pathway in the development of lymphadenopathy and splenomegaly in MRL/lpr mice     

Takiguchi M  Murakami M  Nakagawa I  Rashid MM  Tosa N  Chikuma S  Hashimoto A  Uede T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(1):29-36

MRL/lpr mouse is an established animal model which develops autoimmune diseases including glomerulonephritis, sialoadenitis, hepatitis and inflammatory lung disease. Additionally, it has been reported that lpr strains uniquely accumulate CD3+ CD4- CD8- B220+ (double negative, DN) T cells in lymphoid organs leading to lymphadenopathy and splenomegaly. To investigate the role of CD28/CTLA4-B7 pathway in the development of lymphadenopathy and splenomegaly, MRL/lpr mice were treated with soluble form of CTLA4 molecules, CTLA4IgG, which efficiently blocks this pathway. It was demonstrated that (i) the development of DN T cells was independent of the CD28/CTLA4-B7 pathway, (ii) the CD28/CTLA4-B7 pathway was required for the development of lymphadenopathy and splenomegaly, (iii) the CD28/CTLA4-B7 pathway was important for the accumulation of various cell populations in the lymph node and spleen, (iv) composition of the accumulating cell populations was not altered by CTLA4IgG treatment, and (v) activation of conventional T cells and IL-4 production from conventional T cells were the CD28/CTLA4-B7 pathway dependent. Thus, we concluded that the CD28/CTLA4-B7 pathway was required for the development of full-blown lymphadenopathy and splenomegaly in MRL/lpr mice.  相似文献