Agaricus blazei (H1 strain) was tested for its anticancer activity using a sarcoma 180 (S180) inoculation model and the changing patterns of splenocyte subsets were examined. Its hot-water extract was administered orally to ICR and KSN nude mice that were inoculated with S180. The growth of S180 was significantly inhibited in A.blazei treated groups. Pan T cells significantly increased in all treated groups compared to controls, even in KSN nude mice. Splenocyte subset changes were slightly different between ICR and KSN nude mice. This S180 inoculation model proved to be effective in screening the antitumor effect of basidiomycetes and allowed comparisons of immunological cellular changes between the mouse strains.

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Serum alpha 1-acid glycoprotein (AAG) levels were measured in healthy beagles of various ages (66 male and 74 female) by turbidimetric immunoassay (TIA), and then separately - in pregnant beagles - by single radial immunodiffusion (SRID). The first experiment revealed that serum AAG levels ranged from 40 to 960 μg/ml (mean of 322 ± 202 μg/ml) in male dogs, and from 47 to 833 μg/ml - in female dogs (mean of 316 ± 199 μg/ml), without any significant sex- or age-related variation. The second experiment, however, revealed that serum AAG levels increased in all pregnant beagles and peaked in the middle of gestation at 250-1,000 μg/ml (mean of 634 ± 246 μg/ml). In 7 of 8 dogs the AAG levels peaked about 45 days after ovulation. Despite a high value of 1,210-1,360 μg/ml being observed for serum AAG levels in 3 pregnant beagles inoculated with Staphylococcus aureus, its levels in umbilical cord blood were below the detection limit of SRID (40 μg/ml).

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Stress is one of the important factors that induces reactivation of pseudorabies virus (PrV) in latently infected pigs. We established a murine model of latent PrV infection and examined the effects of mild stress treatment in order to demonstrate that this model simulates natural infection in the pig. Latently infected mice excreted PrV from the nasal cavity under stress treatments consisting of restraint, exposure to cold or transport. Similar reactions have been observed upon treatment with acetylcholine and dexamethasone. The present findings demonstrate that these kinds of mild stress reactivate the virus in murine latent infection models in a manner similar to the induction of latent infection in pigs in the field.

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Serum C-reactive protein (CRP) concentrations in healthy beagle dogs of various ages and in pregnant beagles were measured by enzyme-linked immunosorbent assay (ELISA). Serum CRP concentrations were 1.5-16.0 μg/ml (mean 7.9 ± 3.4 μg/ml) in male, and 1.8-18.9 μg/ml (mean 8.3 ± 4.0 μg/ml) in female dogs. No significant sex-related differences were observed in the values. Further, there were no significant age-related differences either. Serum CRP concentrations increased during pregnancy. The concentration of serum CRP in pregnant dogs peaked at 70.2-90.4 μg/ml (mean 77.5 ± 7.1 μg/ml) 30 or 45 days after ovulation, demonstrating two characteristic features of CRP concentration change in pregnant dogs.

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Despite intensive studies of muscular dystrophy of chicken, the responsible gene has not yet been identified. Our recent studies mapped the genetic locus for abnormal muscle (AM) of chicken with muscular dystrophy to chromosome 2q using the Kobe University (KU) resource family, and revealed the chromosome region where the AM gene is located has conserved synteny to human chromosome 8q11-24.3, where the beta-1 syntrophin (SNTB1), syndecan 2 (SDC2) and Gem GTPase (GEM) genes are located. It is reasonable to assume those genes might be candidates for the AM gene. In this study, we cloned and sequenced the chicken SNTB1, SDC2 and GEM genes, and identified sequence polymorphisms between parents of the resource family. The polymorphisms were genotyped to place these genes on the chicken linkage map. The AM gene of chromosome 2q was mapped 130 cM from the distal end, and closely linked to calbindin 1 (CALB1). SNTB1 and SDC2 genes were mapped 88.5 cM distal and 27.6 cM distal from the AM gene, while the GEM gene was mapped 18.5 cM distal from the AM gene and 9.1 cM proximal from SDC2. Orthologues of SNTB1, SDC2 and GEM were syntenic to human chromosome 8q. SNTB1, SDC2 and GEM did not correspond to the AM gene locus, suggesting it is unlikely they are related to chicken muscular dystrophy. However, this result also suggests that the genes located in the proximal region of the CALB1 gene on human chromosome 8q are possible candidates for this disease.

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We have established a genetic quality testing system for early stage embryos of the mouse. A method of preparation of template DNA for PCR was established using the lysis buffer (1 × PCR reaction buffer supplemented with proteinase K at a concentration of 40 μg/ml) developed by the authors. We demonstrated that two 8-cell embryos of an inbred strain provide sufficient volumes of template DNA for PCR to identify the strain of embryos using four microsatellite markers (D3Mit54, D5Mit18, D6Mit15 and D8Mit50) differentiating 13 inbred strains of mice. This system will be useful in embryo banks that have recently been established worldwide for demonstrating the genetic accuracy of a given strain prior to recovery of live animals.

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To develop a rat model of type 2 diabetic mellitus that simulated the common manifestation of the metabolic abnormalities and resembled the natural history of a certain type 2 diabetes in human population, male Sprague-Dawley rats (4 months old) were injected with low-dose (15 mg/kg) STZ after high fat diet (30% of calories as fat) for two months (L-STZ/2HF). The functional and histochemical changes in the pancreatic islets were examined. Insulin-glucose tolerance test, islet immunohistochemistry and other corresponding tests were performed and the data in L-STZ/2HF group were compared with that of other groups, such as the model of type 1 diabetes (given 50 mg/kg STZ) and the model of obesity (high fat diet). The body weight of rats in the group of rats given 15 mg/kg STZ after high fat diet for two months increased significantly more than that of rats in the group of rats given 50 mg/kg STZ (the model of type 1 diabetes) (595 ± 33 g vs. 352 ± 32 g, p<0.05). Fast blood glucose levels for L-STZ/2HF group were 16.92 ± 1.68 mmol/l, versus 5.17 ± 0.55 mmol/l in normal control and 5.59 ± 0.61 mmol/l in rats given high fat diet only. Corresponding values for fast serum insulin were 0.66 ± 0.15 ng/ml, 0.52 ± 0.13 ng/ml, 0.29 ± 0.11 ng/ml, respectively. Rats of type 2 diabetes (L-STZ/2HF) had elevated levels of triglyceride (TG, 3.82 ± 0.88 mmol/l), and cholesterol(Ch, 2.38 ± 0.55 mmol/l) compared with control (0.95 ± 0.15 mmol/l and 1.31 ± 0.3 mmol/l, respectively) (p<0.05). The islet morphology as examined by immunocytochemistry using insulin antibodies in the L-STZ/2HF group was affected and quantitative analysis showed the islet insulin content was higher than that of rats with type 1 diabetes (P<0.05). We concluded that the new rat model of type 2 diabetes established with conjunctive treatment of low dose of STZ and high fat diet was characterized by hyperglycemia and light impaired insulin secretion function accompanied by insulin resistance, which resembles the clinical manifestation of type 2 diabetes. Such a model, easily attainable and inexpensive, would help further elucidation of the underlying mechanisms of diabetes and its complications.

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Ultrasonic vocalization (USV) responses elicited by air-puff stimuli were compared in regard to both quality and quantity with those elicited by electric foot-shock(s) in adult rats. Frequency pattern, duration, repetition rate and interpulse interval of air-puff-elicited USV were comparable to those observed on foot-shock-elicited USV. Diazepam (0.25-1.0 mg/kg, s.c.) and buspirone (0.1-1.0 mg/kg, s.c.) attenuated equally and dose-dependently the USV responses elicited by both aversive stimuli. Air-puff-elicited USV was specifically attenuated in a dose-dependent manner by the anxiolytic properties of several psychotropic agents: diazepam (1.0-10.0 mg/kg, p.o.), buspirone (10.0-100.0 mg/kg, p.o.), 8-OH-DPAT (0.01-0.5 mg/kg, s.c.). Haloperidol (0.2-1.0 mg/kg, s.c.) weakly attenuated the USV response. Imipramine (0.2-1.0 mg/kg, s.c.) which has no anxiolytic property had no effect. Consequently, air-puff-elicited USV as well as foot-shock-elicited USV may provide a reliable tool for the study of anxiety.

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To develop SMXA recombinant inbred (RI) strains as more valuable genetic resources, 302 microsatellite (Mit) loci were added to the strain distribution patterns (SDP) reported previously. The improved SDP were constructed in a total of 1085 loci containing 484 Mit markers, 571 restriction landmark genomic scanning (RLGS) spot markers and 30 others. This substantially improved SDP can be freely accessed on our homepage (http://www.med.nagoya-u.ac.jp/sisetu/SDP.htm).

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The DS-Nh (DS Non-hair) mouse is a spontaneous hairless mutant of the DS mouse. The inheritance mode of the Nh mutation is autosomal dominant, and the Nh locus is mapped to Chromosome 11. The roles of the Nh mutation in spontaneous dermatitis and IgE hyperproduction were studied using an Nh congenic strain with a genetic background from the BALB/c mouse. In contrast to DS-Nh (Nh/+) mice, BALB/c-Nh (Nh/+) mice under conventional conditions showed a marked increase in serum IgE, without the development of dermatitis. These results suggest that IgE hyperproduction is regulated by the Nh mutation, while other genetic factor(s) are also involved in the development of dermatitis.

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We examined the relationships between Megachiroptera and Microchiroptera, and between Chiroptera and other closely related species by the cross-reactivity of immunoglobulin epitopes. Rabbit polyclonal antibody to bat IgG was used for determining the cross-reactivity by a competitive ELISA method. Megachiroptera and Microchiroptera showed high cross-reactivity, over 95.3%, with each other. However, primates and insectivores showed very low cross-reactivity, 8.6 to 20.2% and 5.3 to 12.7%, respectively. These results suggest that suborders of Chiroptera are monophyletic and Chiroptera have a relatively closer relationship to primates than to insectivores.

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Age-related alterations and differences of weights and those of amino acid concentrations in the cerebrospinal fluid (CSF) were evaluated between Sprague Dawley (SD) rats and Wistar Kyoto (WKY) rats from eight to twenty weeks of age. The weights of SD rats were heavier than WKY rats at all ages. The age-related alterations of the CSF concentration of many amino acids within each strain were significant but showed no significant trend with age. Between the strains, the concentration differences of excitatory and inhibitory amino acids were not frequent although the concentrations of arginine, alanine and threonine were significantly higher in SD rats than in WKY rats. These results suggest that the different CSF concentrations of amino acids may relate to characteristics of rat strains.

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We conducted chromosomal mapping of the pma gene that is a causative gene in the peroneal muscular atrophy mouse, which shows a club foot at birth and unusual gait due to a dropped foot in the adult. Linkage analyses using backcross progeny revealed a significant linkage between the pma gene and three microsatellite markers, D5Mit263 at 73 cM, D5Mit141 and D5Mit97 at 74 cM on Chr 5. The gene order was determined as follows: centromere-D5Mit263-[2.65 cM]-D5Mit141-[2.56 cM]-pma-[5.13 cM]-D5Mit97-telomere.

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In the present study, we used closed colony-Wistar-Imamichi (WI), inbred WI and Long Evans (LE) adult male rats to examine the secretion of ACTH and corticosterone in response to restraint stress. Blood (0.3 ml) was withdrawn through a jugular cannula at 0, 15, 30, 60 and 120 min after the onset of restraint stress. Plasma concentrations of ACTH and corticosterone increased after stress in all groups, but the responses of ACTH and corticosterone secretion were higher in LE rats than in WI rats. Present data suggest that the LE rat might be a good model as a high-response strain and the closed colony or the inbred WI rat might be a good model as a low-response strain in restraint stress experiments.

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The parotid and mandibular glands of the cotton rat were examined by light and transmission electron microscopy. Parotid gland: Acinar cells were serous in nature, and contained electron-dense granules. Intercalated duct cells contained electron-dense granules. Striated duct cells had small granules of moderate and high electron densities. Mandibular gland: Acinar cells were seromucous in nature, and contained granules of low and moderate electron densities. Intercalated duct cells contained granules of moderate and high electron densities. Striated ducts were comprised of two portions - a secretory portion and a striated portion without granules. The secretory portion had many electron-dense granules. A sexual dimorphism was obserbed in these granules, which were smaller and fewer in females than in males.

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