Circadian variations in coagulation and fibrinolytic factors among four different strains of mice

This study examined circadian variation in coagulation and fibrinolytic parameters among Jcl:ICR, C3H/HeN, BALB/cA, and C57BL/6J strains of mice. Plasma plasminogen activator inhibitor 1 (PAI-1) levels fluctuated in a circadian manner and peaked in accordance with the mRNA levels at the start of the active phase in all strains. Fibrinogen mRNA levels peaked at the start of rest periods in all strains, although plasma fibrinogen levels remained constant. Strain differences in plasma antithrombin (AT) activity and protein C (PC) levels were then identified. Plasma AT activity was circadian rhythmic only in Jcl:ICR, but not in other strains, although the mRNA levels remained constant in all strains. Levels of plasma PC and its mRNA fluctuated in a circadian manner only in Jcl:ICR mice, whereas those of plasma prothrombin, factor X, factor VII, prothrombin time (PT), and activated partial thrombin time (APTT) remained constant in all strains. These results suggest that genetic heterogeneity underlies phenotypic variations in the circadian rhythmicity of blood coagulation and fibrinolysis. The circadian onset of thrombotic events might be due in part to the rhythmic gene expression of coagulation and fibrinolytic factors. The present study provides fundamental information about mouse strains that will help to understand the circadian variation in blood coagulation and fibrinolysis.     

Circadian Variations in Coagulation and Fibrinolytic Factors among Four Different Strains of Mice

This study examined circadian variation in coagulation and fibrinolytic parameters among Jcl:ICR, C3H/HeN, BALB/cA, and C57BL/6J strains of mice. Plasma plasminogen activator inhibitor 1 (PAI‐1) levels fluctuated in a circadian manner and peaked in accordance with the mRNA levels at the start of the active phase in all strains. Fibrinogen mRNA levels peaked at the start of rest periods in all strains, although plasma fibrinogen levels remained constant. Strain differences in plasma antithrombin (AT) activity and protein C (PC) levels were then identified. Plasma AT activity was circadian rhythmic only in Jcl:ICR, but not in other strains, although the mRNA levels remained constant in all strains. Levels of plasma PC and its mRNA fluctuated in a circadian manner only in Jcl:ICR mice, whereas those of plasma prothrombin, factor X, factor VII, prothrombin time (PT), and activated partial thrombin time (APTT) remained constant in all strains. These results suggest that genetic heterogeneity underlies phenotypic variations in the circadian rhythmicity of blood coagulation and fibrinolysis. The circadian onset of thrombotic events might be due in part to the rhythmic gene expression of coagulation and fibrinolytic factors. The present study provides fundamental information about mouse strains that will help to understand the circadian variation in blood coagulation and fibrinolysis.     

Cryopreservation of spermatozoa from closed colonies, and inbred, spontaneous mutant, and transgenic strains of rats

We attempted to cryopreserve spermatozoa from closed colonies (Jcl:SD and Jcl:Wistar), and inbred (BN/Crj, F3441 DuCrj, LEW/Crj, Long-Evans and WKY/NCrj), mutant (Zitter [WTC.ZI-zi] and Tremor [TRM]), transgenic (human A-transferase [A], and green fluorescent protein [GFP]) strains of rats. Rat epididymal spermatozoa suspended in cryopreservation solution (23% egg yolk, 8% lactose monohydrate, and 0.7% Equex Stm, pH 7.4, adjusted with 10% Tris [hydroxymethy] aminomethane) were frozen and stored at -196 degrees C. After thawing at 37 degrees C, the spermatozoa were instilled into the tip of each uterine horn of the recipients. A total of five recipient females for each strain were inseminated with cryopreserved spermatozoa, and normal live offspring of all strains (Jcl:SD: 11, Jcl:Wistar: 13, BN/Crj: 9, F344/DuCrj: 28, LEW/Crj: 4, Long-Evans: 6, WKY/NCrj: 8, TRM: 24, WTC.ZI-zi: 27, A: 30 and GFP: 20) were obtained.     

Improvement of high fat-diet-induced insulin resistance in dipeptidyl peptidase IV-deficient Fischer rats

F344/DuCrj rats are genetically deficient in dipeptidyl peptidase IV (DPPIV). This enzyme degrades glucagon-like peptide-1 (GLP-1), which induces glucose-dependent insulin secretion. Glucose tolerance of F344/DuCrj rats is improved as a result of enhanced insulin release induced by high levels of plasma GLP-1. In this study, we fed F344/DuCrj rats and DPPIV-positive F344/Jcl rats, aged five weeks, on a high-fat (HF) diet to examine the effect of DPPIV deficiency on food intake and insulin resistance. F344/Jcl rats gained significantly more body weight and consumed significantly more food than F344/DuCrj rats from Week 4 on either control or HF diet. Glucose excursion in the oral glucose tolerance test (OGTT) was improved in F344/DuCrj rats fed on the control or HF diet at all times examined, compared with F344/Jcl rats. Homeostasis model assessment (HOMA) insulin resistance values of F344/DuCrj and F344/Jcl rats fed on HF diet were higher than those of animals fed on control diet up to Week 6. However, HOMA insulin resistance values of F344/DuCrj rats fed on HF diet became significantly lower than those of F344/Jcl rats on HF diet during Weeks 8-10. The area under the insulin curve in the OGTT at Week 10 showed that the insulin resistance of HF-diet-fed F344/DuCrj rats was greatly ameliorated. Plasma active GLP-1 concentrations of F344/DuCrj rats in the fed state were significantly higher than those of F344/Jcl rats. These observations suggest that DPPIV deficiency results in improved glucose tolerance and ameliorated insulin resistance owing to enhanced insulin release and inhibition of food intake as a result of high active GLP-1 levels.     

Hematology of a Semi-Free-Ranging Colony of Mandrills (Mandrillus sphinx)

We examined hematological parameters for a semifree-ranging population of mandrills to investigate the influence of age and sex, and to establish normative values for age-sex classes. We also investigated the influence of the reproductive cycle on hematological parameters in females and the influence of seasonality on both sexes. We examined hemoglobin concentration, platelet count, white cell count, red cell count, hematocrit, mean cell volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), and differential white cell counts, with a total of 459 observations. Red cell counts, hemoglobin, and hematocrit are significantly lower in females than in males, while female white cell counts are significantly higher. Platelet and white cell counts both decreased with age, while MCV and MCHC (males only) increased with age. Absolute lymphocyte counts also decreased with age. Female reproductive status had little effect on hematology, but melengestrol acetate contraceptive implants resulted in significant increases in hemoglobin, white cell count, red cell count, and hematocrit. Finally, lymphocyte counts increased significantly during the wet season in comparison with dry months, which may be related to increased parasite infection during the wet season. We compare our findings to those for other species, and discuss age-sex patterns in light of mandrill life history. Our results demonstrate the importance of including age-sex class, female reproductive status, and season in studies of hematology and will be useful in further studies of the colony.     

Age and gender related changes in hematological parameters of thoroughbred foals

Abstract

Hematological and biochemical profiles commonly are required in equine medicine. We studied hematological parameters including red blood cells (RBC), white blood cells (WBC), hemoglobin (Hb), hematocrit (PCV), differential leukocyte counts, mean cell volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) in thoroughbred foals at different ages and for both sexes. Sixty healthy thoroughbred foals, 1 day, 3 days and 1 year old were used. Each age group consisted of 10 male and 10 female animals. We found significant differences related to age in RBC values of females, PCV, MCV values of males, WBC, neutrophil percentages, lymphocyte percentages, monocyte percentages of females, and eosinophil percentages and basophil percentages. Significant differences related to gender were found only with regard to PCV at 1 year and WBC at 1 day. The hematological parameters of thoroughbred foals up to one year old may be useful for evaluating and monitoring the health of these animals.     

Sleep-time variation for ethanol and the hypnotic drugs tribromoethanol, urethane, pentobarbital, and propofol within outbred ICR mice.

To evaluate the phenotypic variation within a commercial outbred mouse stock, we examined sleep-time (or duration of loss of righting reflex) of outbred ICR mice after i.p. injection of ethanol (4.0 g/kg of body weight), urethane (1.3 g), tribromoethanol (250 mg), and pentobarbital (60 mg), and after i.v. injection of propofol (30 mg). We observed high-grade individual differences in sleep-time that ranged from 0 to 179 min, 83.1 +/- 4.3 (mean and SEM of 100 mice) for ethanol; 0 to 169 min, 64.5 +/- 3.1 for pentobarbital; 0 to 160 min, 36.6 +/- 3.6 for urethane; 0 to 120 min, 21.5 +/- 2.2 for tribromoethanol; and 3 to 20.5 min, 7.1 +/- 0.3 for propofol. This extensive phenotypic variance within the outbred stock was as great as the variation reported among inbred strains or selected lines, and the varied susceptibility within the colony was inherited by Jcl:ICR-derived inbred strains IAI, ICT, IPI, and IQI. The range of sleep-time variance for ethanol, pentobarbital, urethane, tribromoethanol, and propofol within four-way cross hybrid Jcl:MCH(ICR) mice was 86.6%, 63.3%, 124%, 61.0%, and 53.1% that of outbred Jcl:ICR mice, respectively. The present study indicates that phenotypic variance within an outbred Jcl:ICR stock was at high risk for susceptibility to the drugs that depress the central nervous system and that Jcl:ICR-derived inbreds may be an excellent source of animal models for studying the anesthesia gene.     

Strain differences of the ability to hydroxylate methotrexate in rats

Converting activity of methotrexate (MTX) to 7-hydroxymethotrexate (7-OH-MTX) was examined using eight strains of rats. Marked variability of the activity was found in liver cytosols from the rats. The highest activity was observed with Sea:SD rats, followed by LEW/Sea and Jcl:Wistar rats. The lowest activity was observed with WKA/Sea rats. The difference in the activity between Sea:SD and WKA/Sea strains was 104-fold. The variation was correlated to the strain difference of benzaldehyde oxidase activity in the rats. The cytosolic 7-hydroxylase activities in other tissues of Sea:SD rats were much higher than those of WKA/Sea, similarly to the case in liver. The liver microsomes of Sea:SD rats exhibited no 7-hydroxylase activity toward MTX even in the presence of NADPH. The cytosolic 7-hydroxylating activity of the livers of Sea:SD rats was inhibited by menadione, β-estradiol, chlorpromazine and disulfiram, inhibitors of aldehyde oxidase, but not oxypurinol, an inhibitor of xanthine oxidase. The purified aldehyde oxidase from the livers of Sea:SD rats exhibited a significant 7-hydroxylating activity toward MTX. However, xanthine oxidase had no ability to hydroxylate MTX. These facts suggest that MTX hydroxylating activity in rats is predominantly due to aldehyde oxidase, and the strain differences are due to the variations of the flavoenzyme level.     

Hematology of common marmosets (Callithrix jacchus)

The hematology of the common marmoset (Callithrix jacchus) was investigated to provide reference values for the normal animal. Red blood cell counts, white blood cell counts, hemoglobins, mean cell volumes and differential white blood cell mean values were determined for Texas A&M colony-born animals and those obtained from the wild. The analyses were completed on 31 animals, three times each, for a total of 93 analyses, which included 16 colony-born and 15 wild-born marmosets. The hematological mean values found for marmosets were similar to those mean values reported for humans. The ranges for the hematology values were much narrower in the colony-born marmosets, and the average white blood cell count was significantly lower in these animals. This indicated that it is possible to produce and maintain a more uniform animal in the colony environment and, consequently, these animals are more suitable than wild-born animals for use as models for human research.     

White matter development in early puberty: a longitudinal volumetric and diffusion tensor imaging twin study

White matter microstructure and volume show synchronous developmental patterns in children. White matter volume increases considerably during development. Fractional anisotropy, a measure for white matter microstructural directionality, also increases with age. Development of white matter volume and development of white matter microstructure seem to go hand in hand. The extent to which the same or different genetic and/or environmental factors drive these two aspects of white matter maturation is currently unknown. We mapped changes in white matter volume, surface area and diffusion parameters in mono- and dizygotic twins who were scanned at age 9 (203 individuals) and again at age 12 (126 individuals). Over the three-year interval, white matter volume (+6.0%) and surface area (+1.7%) increased, fiber bundles expanded (most pronounced in the left arcuate fasciculus and splenium), and fractional anisotropy increased (+3.0%). Genes influenced white matter volume (heritability ~85%), surface area (~85%), and fractional anisotropy (locally 7% to 50%) at both ages. Finally, volumetric white matter growth was negatively correlated with fractional anisotropy increase (r = -0.62) and this relationship was driven by environmental factors. In children who showed the most pronounced white matter growth, fractional anisotropy increased the least and vice-versa. Thus, white matter development in childhood may reflect a process of both expansion and fiber optimization.     

Dietary conjugated linoleic acid reduces body fat mass and affects gene expression of proteins regulating energy metabolism in mice

ICR and C57BL/6J mice were fed experimental diets containing either a 2% fatty acid preparation rich in conjugated linoleic acid (CLA) or a preparation rich in linoleic acid and free of CLA for 21 days. CLA greatly decreased weights of white adipose tissue and interscapular brown adipose tissue in the two strains. CLA reduced mRNA levels of glucose transporter 4 (Glut 4) in white and brown adipose tissue of both strains. A CLA-dependent decrease in mRNA levels of peroxisome proliferator activated receptor (PPAR) gamma was seen in interscapular brown adipose tissue of both strains and in white adipose tissue of C57BL/6J but not ICR mice. Dietary CLA was found to cause a decrease in the mRNA levels of uncoupling protein (UCP) 1 in brown adipose tissue when the value was corrected for the expression of a house-keeping gene (beta-actin) in the two strains. Uncorrected values were, however, indistinguishable between the animals fed the CLA diet and CLA-free diet. UCP 3 expression in brown adipose tissue was much lower in mice fed the CLA diet than in those fed the control diet in both strains. In contrast, CLA greatly up-regulated the gene expression of UCP 2 in brown adipose tissue. Dietary CLA also increased UCP 2 mRNA level in skeletal muscle. It is apparent that dietary CLA decreases white and brown adipose tissue mass, accompanying changes in the gene expression of proteins regulating energy metabolism in white and brown adipose tissues, and skeletal muscle of mice.     

Strain differences to effects of aging on concentrations of amino acids in cerebrospinal fluid between Sprague Dawley rat and Wistar Kyoto rat.

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.     

SHRSP/Izm and WKY/NCrlCrlj rats having a missense mutation in Abcg5 deposited plant sterols in the body, but did not change their biliary secretion and lymphatic absorption-comparison with Jcl:Wistar and WKY/Izm rats

We had previously found plant sterols deposited in the bodies of stroke-prone spontaneously hypertensive rats (SHRSP)/Sea and Wistar Kyoto (WKY)/NCrlCrlj rats that had a missense mutation in the Abcg5 cDNA sequence that coded for ATP-binding cassette transporter (ABC) G5. We used SHRSP/Izm, WKY/NCrlCrlj, and WKY/Izm rats in the present study to determine the mechanisms for plant sterol deposition in the body. Jcl:Wistar rats were used as a control strain. A diet containing 0.5% plant sterols fed to the rats resulted in plant sterol deposition in the body of SHRSP/Izm, but not in WKY/Izm or Jcl:Wistar rats. Only a single non-synonymous nucleotide change, G1747T, resulting in a conservative cysteine substitution for glycine at amino acid 583 (Gly583Cys) in Abcg5 cDNA was identified in the SHRSP/Izm and WKY/NCrlCrlj rats. However, this mutation was not found in the WKY/Izm or Jcl:Wistar rats. No significant difference in the biliary secretion or lymphatic absorption of plant sterols was apparent between the rat strains with or without the missense mutation in Abcg5 cDNA. Our observations suggest that plant sterol deposition in rat strains with the missense mutation in Abcg5 cDNA can occur, despite there being no significant change in the biliary secretion or lymphatic absorption of plant sterols.     

A new variant of the Es-4 locus in the rat

A new variant of kidney esterase in the DK/Nac rat strain is reported. The new esterase was tentatively named ES-4C determined by a third allele of the Es-4 locus of Linkage Group V (LGV). Strain distribution was surveyed using 17 inbred strains, but no strain except for the DK/Nac strain possessed the ES-4C type. Although we surveyed outbred stocks (Jcl: Wistar and Jcl: SD) we could not find rats carrying the ES-4C type. Genetic analysis of the ES-4C type was carried out using mating experiments between DK/Nac and BUF/Nac (ES-4B). The results indicated that the new variant was controlled by the Es-4 locus and it was named the Es-4c allele.     

Hemograms for and nutritional condition of migrant bald eagles tested for exposure to lead

Plasma proteins, hematocrit, differential blood counts were examined and nutritional condition was estimated for bald eagles (Haliaeetus leucocephalus) trapped (n = 66) during antumn migration, 1994-95 at Galloway Bay (Saskatchewan, Canada), for the purposes of estimating prevalence of exposure to lead. Sex and age differences in hematocrit and plasma proteins were not observed; however, female eagles exhibited larger median absolute heterophil counts than males. Hematologic values were similar to those previously reported from eagles in captivity. Departures from expected hematological values from a healthy population of eagles were not observed in birds with elevated levels of blood lead (> or =0.200 microg/ml). Similarly, nutritional condition was not related to blood-lead concentrations. Therefore, it appears that lead exposure in this population was below a threshold required to indicate toxicological alteration in the hematological values and index of nutritional condition that we measured.     

Protective role of <Emphasis Type="SmallCaps">l</Emphasis>-ascorbic acid on antioxidant defense system in erythrocytes of albino rats exposed to nickel sulfate

In this experimental study, we investigated whether l-ascorbic acid has any influence on the blood antioxidant defense system, lipid peroxidation and hematological parameters of the albino rats exposed to nickel sulfate(NiSO₄).Twenty four adult rats were divided into four groups of six animals in each group. The control rats were untreated and comprised Group I. Group II rats were administered nickel sulfate (2.0 mg/100 g b.wt.; intraperitonially, i.p.). Group II rats were treated orally l-ascorbic acid (50 mg/100 g b.wt.) and Group IV rats were given both nickel sulfate and l-ascorbic acid simultaneously on alternate days until the tenth dose. The hematological parameters were assessed: red blood corpuscle counts, packed cell volume %, hemoglobin concentration, white blood corpuscle counts and platelets count decreased significantly and clotting time increased significantly in nickel treated rats. We also observed increase malondialdehyde (MDA) and decrease glutathione level (GSH) in erythrocytes of nickel treated rats. The activities of erythrocyte antioxidant enzymes like superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) were significantly increased in rats treated with nickel sulfate. Simultaneously treatment of l-ascorbic acid exhibited a possible protective role on the toxic effect of nickel sulfate on the hematological values, erythrocyte MDA and GSH concentrations as well as antioxidant enzymatic defense system.     

Natural dental caries in molars of osteogenic disorder Shionogi rats

Osteogenic disorder Shionogi (ODS) rats are genetically defective in ascorbic acid biosynthesis. They exhibit a gait abnormality due to dysfunctional bone formation and display various dental abnormalities. Conditions of the oral cavity and tooth quality both influence the development of dental caries. This study was designed to determine the characteristics of dental caries in ODS/ ShiJclod/od rats. Caries were scored and compared among ODS/ShiJclod/od, ODS/ShiJcl+/+, and Jcl:Wistar retired breeders. Among male rats, the caries scores of the ODS/ShiJclod/od and ODS/ShiJcl+/+ groups were similar to each other but greater than those in Jcl:Wistar rats, whereas among female rats, caries scores in ODS/ShiJclod/od animals were equivalent to or somewhat greater than those in ODS/ShiJcl+/+ rats, whose scores were markedly greater than those of Jcl:Wistar rats. The results suggest that ODS/ShiJcl rats were more susceptible to dental caries than were Jcl:Wistar rats. Under the conditions of the study, caries scores between ODS/ ShiJclod/od and ODS/ShiJcl+/+ rats differed only among parous females.     

SHRSP/Izm and WKY/NCrlCrlj Rats Having a Missense Mutation in Abcg5 Deposited Plant Sterols in the Body,but Did Not Change Their Biliary Secretion and Lymphatic Absorption—Comparison with Jcl:Wistar and WKY/Izm Rats

We had previously found plant sterols deposited in the bodies of stroke-prone spontaneously hypertensive rats (SHRSP)/Sea and Wistar Kyoto (WKY)/NCrlCrlj rats that had a missense mutation in the Abcg5 cDNA sequence that coded for ATP-binding cassette transporter (ABC) G5. We used SHRSP/Izm, WKY/NCrlCrlj, and WKY/Izm rats in the present study to determine the mechanisms for plant sterol deposition in the body. Jcl:Wistar rats were used as a control strain. A diet containing 0.5% plant sterols fed to the rats resulted in plant sterol deposition in the body of SHRSP/Izm, but not in WKY/Izm or Jcl:Wistar rats. Only a single non-synonymous nucleotide change, G1747T, resulting in a conservative cysteine substitution for glycine at amino acid 583 (Gly583Cys) in Abcg5 cDNA was identified in the SHRSP/Izm and WKY/NCrlCrlj rats. However, this mutation was not found in the WKY/Izm or Jcl:Wistar rats. No significant difference in the biliary secretion or lymphatic absorption of plant sterols was apparent between the rat strains with or without the missense mutation in Abcg5 cDNA. Our observations suggest that plant sterol deposition in rat strains with the missense mutation in Abcg5 cDNA can occur, despite there being no significant change in the biliary secretion or lymphatic absorption of plant sterols.     

Selenium status in Turkey

This study was initiated to evaluate the status of selenium in Turkish residents. Serum selenium level of 76 healthy children, living in Ankara, aged 2 mo-13 y was determined by a spectrofluorometric method. Average selenium level was found to be 88.1 +/- 12.4 micrograms/L (mean +/- SD). Selenium levels showed a tendency to increase with age and mean selenium level in early infancy was lower than that of school children; no relation to the sex and hematological parameters such as hemoglobin concentration and white blood cell counts were observed.