Lesion of the OVLT markedly attenuates chronic DOCA-salt hypertension in rats.

Lesions of the anteroventral third ventricle (AV3V region) are known to prevent many forms of experimental hypertension, including mineralocorticoid [deoxycorticosterone acetate (DOCA)-salt] hypertension in the rat. However, AV3V lesions include the organum vasculosum of the lamina terminalis (OVLT), portions of the median preoptic nucleus, and efferent fibers from the subfornical organ (SFO), thereby limiting the ability to define the individual contribution of these structures to the prevention of experimental hypertension. Having previously reported that the SFO does not play a significant role in the development of DOCA-salt hypertension, the present study was designed to test the hypothesis that the OVLT is necessary for DOCA-salt hypertension in the rat. In uninephrectomized OVLT-lesioned (OVLTx; n = 6) and sham-operated ( n = 4) Sprague-Dawley rats consuming a 0.1% NaCl diet and 0.9% NaCl drinking solution, 24-h mean arterial pressure (MAP) was recorded telemetrically 5 days before and 21 days after DOCA implantation (100 mg sc per rat). No differences in control MAP were observed between groups. The chronic pressor response to DOCA was attenuated in OVLTx rats such that MAP increased to 133 ± 3 mmHg in sham-operated rats by day 21 of DOCA compared with 120 ± 4 mmHg (means ± SE) in OVLTx rats. These results support the hypothesis that the OVLT is an important brain site of action for the pathogenesis of DOCA-salt hypertension in the rat.

Western diet-induced hepatic steatosis and alterations in the liver transcriptome in adult Brown-Norway rats.

BACKGROUND: The purpose of this study was to investigate the effects of sub-chronic high fat, high sucrose diet (also termed 'Westernized diet' or WD) feeding on the liver transcriptome during early nonalcoholic fatty liver disease (NAFLD) development. METHODS: Brown Norway male rats (9 months of age) were randomly assigned to receive ad libitum access to a control (CTL; 14 % kcal fat, 1.2 % sucrose by weight) diet or WD (42 % kcal from fat, 34 % sucrose by weight) for 6 weeks. RESULTS: Six weeks of WD feeding caused hepatic steatosis development as evidenced by the 2.25-fold increase in liver triacylglycerol content, but did not induce advanced liver disease (i.e., no overt inflammation or fibrosis) in adult Brown Norway rats. RNA deep sequencing (RNA-seq) revealed that 94 transcripts were altered in liver by WD feeding (46 up-, 48 down-regulated, FDR < 0.05). Specifically, the top differentially regulated gene network by WD feeding was 'Lipid metabolism, small molecular biochemistry, vitamin and mineral metabolism' (Ingenuity Pathway Analysis (IPA) score 61). The top-regulated canonical signaling pathway in WD-fed rats was the 'Superpathway of cholesterol biosynthesis' (10/29 genes regulated, p = 1.68E-17), which coincides with a tendency for serum cholesterol levels to increase in WD-fed rats (p = 0.09). Remarkably, liver stearoyl-CoA desaturase (Scd) mRNA expression was by far the most highly-induced transcript in WD-fed rats (approximately 30-fold, FDR = 0.01) which supports previous literature underscoring this gene as a crucial target during NAFLD development. CONCLUSIONS: In summary, sub-chronic WD feeding appears to increase hepatic steatosis development over a 6-week period but only induces select inflammation-related liver transcripts, mostly acute phase response genes. These findings continue to outline the early stages of NAFLD development prior to overt liver inflammation and advanced liver disease.

Plasma syndecan-1 concentration as a biomarker for endothelial glycocalyx degradation in septic adult horses.

BACKGROUND: Limited information is available regarding endothelial glycocalyx degradation during sepsis in horses. Plasma syndecan-1 concentrations are increased in consequence of sepsis in other species and have been useful for prognostication. OBJECTIVES: To determine whether plasma syndecan-1 levels are increased in adult horses affected with sepsis. STUDY DESIGN: Retrospective cohort study. METHODS: Adult horses were assigned to one of three groups based on results of physical and laboratory examinations, clinical diagnosis, and results of previously described SIRS classification: Group 1 horses included healthy, nonseptic horses; Group 2 included horses in which clinical illness was identified but that were not considered to be septic; Group 3 included horses with a clinical diagnosis of sepsis. Plasma syndecan-1 concentration was determined in blood obtained at admission into the hospital for each horse, using an equine specific ELISA. Data were analysed using ANOVA and linear regression (p ≤ 0.05). RESULTS: One hundred and ninety-one horses were included and divided into three groups. Scores for SIRS were highest for Group 3 horses and lowest in Groups 1 and 2. Plasma syndecan-1 concentrations in Group 3 horses (50.73 ± 84.24 µg/ml; n = 42) were greater than those for Group 1 (15.69 ± 11.28 µg/ml; n = 66) and Group 2 (16.88 ± 15.30 µg/ml; n = 83). There was no difference regarding syndecan concentrations between Groups 1 and 2. MAIN LIMITATIONS: Retrospective study design, solitary time point of measurement for each patient, and lack of a widely accepted consensus regarding definitive diagnosis of sepsis in adult horses. CONCLUSIONS: Circulating plasma levels of syndecan-1, a biochemical marker of endothelial glycocalyx damage, are increased in septic adult horses.

Optimal filling solution for silicone Foley catheter balloons.

We assessed whether saline, sterile water, or air better maintained filling volume and diameter in a veterinary silicone Foley bulb. The bulbs of 45 8-French silicone Foley catheters were inflated: 15 with 5 mL of sterile water (SW bulbs), 15 with 0.9% saline (S bulbs), and 15 with air (A bulbs). The bulbs were submerged in 30 mL of synthetic urine in a 50 mL conical tube in a 38°C water bath. Five catheters from each group were removed on days 3, 5, and 10 to measure bulb volume and diameter. On days 3 and 5, volume and diameter of SW or S bulbs were significantly greater than those of A bulbs, but were not significantly different from one another. At day 10, only 1 S bulb remained intact, 4 of the 5 SW bulbs were intact, the average volume of the SW bulbs was 2.8 mL, and the A bulbs were all deflated. We conclude that sterile water and 0.9% saline are both acceptable for Foley bulb inflation of 5 d or less, but sterile water might be preferred if bulb inflation must be maintained for more than 5 d.

Laminitis and the equine metabolic syndrome.

Although much has been written about laminitis in the context of its association with inflammatory processes, recognition is growing that most cases of laminitis examined by veterinarians in private practice are those associated with pasture grazing, obesity, and insulin resistance (IR). The term 'endocrinopathic laminitis' has been adopted to classify the instances of laminitis in which the origin seems to be more strongly associated with an underlying endocrinopathy, such as either IR or the influence of corticosteroids. Results of a recent study suggest that obesity and IR represent the most common metabolic and endocrinopathic predispositions for laminitis in horses. IR also plays an important role in the pathogenesis of laminitis that develops when some horses or ponies are allowed to graze pastures at certain times of the year. The term equine metabolic syndrome (EMS) has been proposed as a label for horses whose clinical examination results (including both physical examination and laboratory testing) suggest heightened risk for developing laminitis as a result of underlying IR.

Diagnosis, Surveillance and Management of Streptococcus equi subspecies zooepidemicus Infections in Chinchillas (Chinchilla lanigera).

During a 6-mo period, two 5-6 mo old female chinchillas (Chinchilla lanigera) were examined at the University of Colorado Anschutz Medical Campus after the discovery of firm, nonmobile masses in the left ventral cervical and left axillary region. Other than these findings and mild weight loss, both chinchillas' physical exams were normal. Bloodwork revealed an inflammatory leukogram characterized by leukocytosis, toxic neutrophils, lymphopenia, and monocytosis with mild, nonregenerative anemia. At necropsy, both masses were identified as abscesses. Streptococcus equi, subspecies zooepidemicus (S. zooepidemicus) was isolated in pure culture. Histology of the lungs, liver, spleen, and kidneys showed a marked increase in the numbers of both polymorphonuclear leukocytes and lymphocytes. Both animals were deemed unsuitable for research and were euthanized under isoflurane anesthesia by an intracardiac injection of pentobarbital sodium solution. S. zooepidemicus is an opportunistic, commensal organism found in the upper respiratory tract of horses. This organism has been documented to cause disease in other species and is zoonotic. Infections in humans have been reported, resulting in glomerulonephritis, endocarditis, septic arthritis, osteomyelitis, meningitis, and death. To aid in diagnosis and prospective surveillance of this bacteria, oral and nasal swabs were collected from the remaining cohort of chinchillas, and a qPCR screening assay was implemented. Within 12 mo, 4 of 41 additional females tested positive by culture or qPCR, resulting in a disease prevalence of 14% (6 of 43). However, only 2 of the additional 4 S. zooepidemicus positive animals developed clinical signs. The potential for the spread of infection, zoonosis, and adverse effects on research demonstrate that surveillance for S. zooepidemicus should be considered in a biomedical research environment.

Cytologic and histopathologic evaluation of extruded canine degenerate disks.

OBJECTIVE: To describe the cytologic and histopathologic appearance of degenerate disk material in dogs with Hansen type I intervertebral disk disease (IVDD). STUDY DESIGN: Case series. ANIMALS: Dogs (n=45) that had surgical intervention for Hansen type I IVDD (January-November 2007). METHODS: Impression smears and histopathologic sections were prepared from surgically removed degenerate disk material. All slides were evaluated for overall cellularity, quantity and attributes of extracellular matrix, types of cells present, and their cytomorphology. Histopathologic sections were also examined for presence of neovascularization and hemorrhage. RESULTS: Cytologically, 11 of 45 samples consisted of only extracellular matrix, 30 had evidence of inflammation, and 20 contained dysplastic spindloid cells. Histologically, hyaline cartilage predominated in 35 of 45 samples, fibrocartilage in 4, and spindloid cells in 6; 37 of 45 were inflamed, 37 were hemorrhagic, and 13 had neovascularization. CONCLUSIONS: The cytologic and histopathologic appearance of extruded degenerate disk material in dogs is variable and can include dysplastic spindloid cells. CLINICAL RELEVANCE: The variability in cytologic findings and frequent presence of dysplastic spindloid cells suggest that cytology alone may not be a reliable tool to differentiate degenerate canine disk material from a mesenchymal neoplasm.

Opposing effects of S-equol supplementation on metabolic and behavioral parameters in mice fed a high-fat diet.

Phytoestrogens, such as daidzein and genistein, may be used to treat various hormone-dependent disorders. Daidzein can be metabolized by intestinal microbes to S-equol. However, not all individuals possess bacteria producing this metabolite, resulting in categorization of equol vs nonequol producers. Past human and rodent studies have suggested that supplementation of this compound might yield beneficial metabolic and behavioral effects. We hypothesized that administration of S-equol to diet-induced obese male and female mice would mitigate potential diet-induced metabolic and comorbid neurobehavioral disorders. To test this possibility, we placed 5-week-old C57 mice on a high-fat diet (HFD) to mimic the diet currently consumed by many Western adults. Animals were randomly assigned to S-equol supplementation (10 mg/kg body weight) or vehicle control group. After 4 weeks on HFD with or without S-equol supplementation, metabolic and behavioral phenotyping was performed. Although the initial hypothesis proposed that S-equol treatment would improve metabolic and neurobehavioral outcomes, this supplementation instead exacerbated aspects of HFD-induced metabolic disease, as indicated by suppressed physical activity in treated individuals, reduced energy expenditure in treated males, and serum chemistry changes (hyperglycemia in treated individuals; hyperinsulinemia and hypoleptinemia in treated males). Conversely, S-equol individuals exhibited less anxiety-like and depressive-like behaviors, as evidenced by increased exploratory time in the elevated plus maze by treated males and increased time spent mobile in the tail suspension test for treated individuals. In summary, S-equol may be beneficial in mitigating depression and anxiety disorders in individuals, but for indeterminate reasons, supplementation may worsen facets of metabolic disorders in obese individuals.

Glucose lowering effects of inhaled insulin in healthy cats.

Inhaled medications have proven effective and well tolerated in cats, and inhaled insulin has been used successfully for the management of diabetes mellitus in humans. Thus, we hypothesize that delivery of aerosolized regular insulin can lower blood glucose in healthy cats. Five adult cats were administered aerosolized 0.9% saline (IS), regular insulin intravenously (IV) 0.5 U/kg, and aerosolized regular insulin 15 U/kg (I15) and 25 U/kg (I25) and blood glucose was evaluated. Mean blood glucose was significantly lower at 15, 30 and 45 min in the I25 and IV groups compared to baseline. Similarly, the IV and I25 groups had a significantly greater maximal percent change in blood glucose than the IS group. Significantly more cats developed severe hypoglycemia (<50 mg/dl; 2.7 mmol/l) in the IV and I25 groups than in the IS group. Results of this study demonstrate that aerosolized insulin can effectively lower blood glucose concentrations in healthy cats.

Comparison of a semiquantitative point-of-care assay for the detection of canine microalbuminuria with routine semiquantitative methods for proteinuria.

BACKGROUND: It has been speculated that renal disease can be identified through the detection and quantification of microalbuminuria, however, reliable measurement of albuminuria in any quantity can be challenging. Recently, a new point-of-care immunoassay was validated for the specific detection of microalbuminuria and early renal disease in dogs. OBJECTIVES: The goal of this study was to determine if measurement of microalbuminuria by the point-of-care immunoassay correlated with results from routine semiquantitative methods for detecting proteinuria in dogs. METHODS: One hundred and thirty-eight urine samples, from 133 different dogs, submitted for urinalysis to the Clinical Pathology Laboratory at the University of Missouri-Columbia Veterinary Medical Teaching Hospital were eligible for the study. Samples that contained >20 RBC/high power field (hpf) or >20 WBC/hpf were excluded, as were samples with insufficient volume to complete all tests. All samples were evaluated with a urinary dipstick with or without a sulfosalicylic acid turbidimetric test, a urine protein:creatinine (UPC) ratio, and the immunoassay for microalbuminuria. Data were analyzed by the Spearman rank order correlation. RESULTS: Microalbuminuria results correlated significantly with those of the dipstick (r = 0.715), sulfosalicylic acid test (r = 0.742), and UPC ratio (r = 0.830). Correlation between the immunoassay and UPC ratio was the same (r = 0.830) when only samples with trace or 1+ proteinuria by dipstick were analyzed (n = 51). CONCLUSIONS: The point-of-care immunoassay results for microalbuminuria correlated with the results of semiquantitative methods for detecting total proteinuria in dogs. Routine methods for canine proteinuria appear to be adequate for determining whether further testing for renal disease is warranted.

Stress Leukogram Induced by Acute and Chronic Stress in Zebrafish (Danio rerio).

The use of zebrafish (Danio rerio) as an animal model for experimental studies of stress has increased rapidly over the years. Although many physiologic and behavioral characteristics associated with stress have been defined in zebrafish, the effects of stress on hematologic parameters have not been described. The purpose of our study was to induce a rise in endogenous cortisol through various acute and chronic stressors and compare the effects of these stressors on peripheral WBC populations. Acutely stressed fish underwent dorsal or full-body exposure to air for 3 min, repeated every 30 min over the course of 90 min. Chronically stressed fish underwent exposure to stressors twice daily over a period of 5 d. After the last stressful event, fish were euthanized, and whole blood and plasma were obtained. A drop of whole blood was used to create a blood smear, which was subsequently stained with a modified Wright-Giemsa stain and a 50-WBC differential count determined. Plasma cortisol levels were determined by using a commercially available ELISA. Endogenous cortisol concentrations were significantly higher in both stressed groups as compared with control fish. Acutely stressed fish demonstrated significant lymphopenia, monocytosis, and neutrophilia, compared with unstressed, control fish. Chronic stress induced lymphopenia and monocytosis but no significant changes in relative neutrophil populations in zebrafish. The changes in both stressed groups most likely are due to increases in endogenous cortisol concentrations and represent the first description of a stress leukogram in zebrafish.

Bisphenol A (BPA) in the serum of pet dogs following short-term consumption of canned dog food and potential health consequences of exposure to BPA.

Bisphenol A (BPA) is a widely present endocrine disruptor chemical found in many household items. Moreover, this chemical can bioaccumulate in various terrestrial and aquatic sources; thereby ensuring continual exposure of animals and humans. For most species, including humans, diet is considered the primary route of exposure. However, there has been little investigation whether commercial-brands of dog foods contain BPA and potential health ramifications of BPA-dietary exposure in dogs. We sought to determine BPA content within dog food, whether short-term consumption of these diets increases serum concentrations of BPA, and potential health consequences, as assessed by potential hematological, serum chemistry, cortisol, DNA methylation, and gut microbiome changes, in dogs associated with short-term dietary exposure to BPA. Fourteen healthy privately-owned dogs were used in this study. Blood and fecal samples were collected prior to dogs being placed for two-weeks on one of two diets (with one considered to be BPA-free), and blood and fecal samples were collected again. Serum/plasma samples were analyzed for chemistry and hematology profiles, cortisol concentrations, 5-methylcytosine in lymphocytes, and total BPA concentrations. Fecal samples were used for microbiome assessments. Both diets contained BPA, and after two-weeks of being on either diet, dogs had a significant increase in circulating BPA concentrations (pre-samples=0.7±0.15ng/mL, post-samples=2.2±0.15ng/mL, p<0.0001). Elevated BPA concentrations positively correlated with increased plasma bicarbonate concentrations and associated with fecal microbiome alterations. Short-term feeding of canned dog food increased circulating BPA concentrations in dogs comparable to amounts detected in humans, and greater BPA concentrations were associated with serum chemistry and microbiome changes. Dogs, who share our internal and external environments with us, are likely excellent indicators of potential human health concerns to BPA and other environmental chemicals. These findings may also have relevance to aquatic and terrestrial wildlife.

Modulation of leptin, insulin, and growth hormone in obese pony mares under chronic nutritional restriction and supplementation with ractopamine hydrochloride.

Horses fed beyond their nutritional requirement and that are physically inactive will develop obesity, which is often accompanied by insulin resistance and heightened risk of laminitis. The use of pharmacologic agents in combination with nutritional restriction may promote weight loss in obese horses unable to exercise because of laminitic pain. This study shows that reducing feed intake of brome grass hay to 75% of ad libitum intake in obese pony mares reduces body weight without induced exercise. Additional supplementation of ractopamine hydrochloride for 6 weeks resulted in a tendency for increased weight loss. Subsequent modulation of obesity-associated hormones, leptin and insulin, as a result of caloric restriction was observed.

Structural equation modeling identifies markers of damage and function in the aging male Fischer 344 rat.

The male Fischer 344 rat is an established model to study progressive renal dysfunction that is similar, but not identical, to chronic kidney disease (CKD) in humans. These studies were designed to assess age-dependent alterations in renal structure and function at late-life timepoints, 16-24 months. Elevations in BUN and plasma creatinine were not significant until 24 months, however, elevations in the more sensitive markers of function, plasma cystatin C and proteinuria, were detectable at 16 and 18 months, respectively. Interestingly, cystatin C levels were not corrected by caloric restriction. Urinary Kim-1, a marker of CKD, was elevated as early as 16 months. Klotho gene expression was significantly decreased at 24 months, but not at earlier timepoints. Alterations in renal structure, glomerulosclerosis and tubulointerstitial fibrosis, were noted at 16 months, with little change from 18 to 24 months. Tubulointerstitial inflammation was increased at 16 months, and remained similar from 18 to 24 months. A SEM (structural equation modeling) model of age-related renal dysfunction suggests that proteinuria is a marker of renal damage, while urinary Kim-1 is a marker of both damage and function. Taken together, these results demonstrate that age-dependent nephropathy begins as early as 16 months and progresses rapidly over the next 8 months.

Evaluation of a continuous glucose monitoring system for use in veterinary medicine.

BACKGROUND: With the emergence of continuous glucose monitoring systems being used to provide a detailed glucose picture in humans, a commercially available system (CGMS(R), Medtronic Minimed, Northridge, CA) was examined for use in veterinary species. METHODS: Adult, clinically normal horses (n = 7), cats (n = 3), dogs (n = 4), and cows (n = 5) were studied. Cats (n = 4), dogs (n = 5), and one horse with diabetes were included in the study. Several of the normal horses, including the horse with diabetes, and one cow were subjected to an intravenous glucose tolerance test. The CGMS was attached to each animal, and the recorded interstitial glucose concentrations were compared with whole blood glucose concentrations as determined by a point-of-care glucose meter. Events such as insulin administration, feeding, travel, or administration of intravenous glucose were all noted and compared with results from the CGMS. RESULTS: There was a positive correlation between interstitial and whole blood glucose concentrations for all the clinically normal species, those with diabetes mellitus, and those receiving intravenous glucose. Events such as feeding, glucose or insulin administration, and transport to the clinic were noted by the owner or clinician and could be identified on the graph and correlated with time of occurrence. CONCLUSIONS: Our data indicate that the use of the CGMS is valid for use in the species examined. Use of this system alleviated the need for multiple blood samples and the stress associated with obtaining those samples. This system may provide greater monitoring capabilities in patients with diabetes and promote the diagnostic and research potential of serial glucose monitoring in veterinary species.

Cloning and characterization of feline brain natriuretic peptide.

Brain (B-type) natriuretic peptide (BNP) is a cardiac hormone involved in regulation of fluid balance and blood pressure homeostasis of mammalian species. BNP sequence is species-specific and considered to be a significant prognostic and diagnostic marker for cardiac dysfunction. Using conventional polymerase chain reaction and amplification of cDNA 3'- and 5'-ends, a total of 1500 nucleotides encompassing the entire feline BNP gene were characterized. The feline BNP gene is organized in three exons separated by two introns. The complete transcript of 736 nucleotides was characterized, including 396 nucleotides encoding feline preproBNP. The preproBNP consisted of a signal peptide of 26 amino acids and a proBNP of 106 residues. The predicted mature BNP comprised 35 amino acids with likely 26- and 29-aa isomers, including a histidine residue at the C-terminus. Based on the similarity of BNP prepropeptide sequences, a phylogenetic relationship is presented for mammalian species including human, cat, cattle, dog, mouse, rat, sheep and swine.

Alkaline phosphatase expression in tissues from glucocorticoid-treated dogs.

OBJECTIVE: To determine the effect of glucocorticoids on the induction of alkaline phosphatase (ALP) isoenzymes in the liver, kidneys, and intestinal mucosa, 3 tissues that are principally responsible for ALP synthesis in dogs. SAMPLE POPULATION: Tissues from the liver, kidneys, and intestinal mucosa of 6 dogs treated with 1 mg of prednisone/kg/d for 32 days and 6 untreated control dogs. PROCEDURES: Using canine-specific primers for the ALP isoenzymes, a reverse transcription-polymerase chain reaction assay was designed to measure liver ALP (LALP) and intestinal ALP (IALP) mRNA and heterogeneous nuclear RNA (hnRNA) expression in tissues from the liver and kidneys and intestinal mucosa of glucocorticoid-treated and control dogs. Tissue ALP isoenzyme activities were compared between the groups. RESULTS: The LALP activity and mRNA concentrations increased in tissues of the liver and kidneys in dogs treated with prednisone, whereas LALP hnRNA increased only in liver tissues. The IALP activity and mRNA expression increased in intestinal mucosa and liver tissues in prednisone-treated dogs. We did not detect an increase in IALP hnRNA expression in these tissues. CONCLUSIONS AND CLINICAL RELEVANCE: Synthesis of ALP is increased in the liver, kidneys, and intestinal mucosa of dogs in response to prednisone treatment. This response appears to be regulated at the transcriptional level, but mechanisms may differ between LALP and IALP.

Kinetics of mRNA expression of alkaline phosphatase isoenzymes in hepatic tissues from glucocorticoid-treated dogs.

OBJECTIVE: To clone segments of the canine liver alkaline phosphatase (LALP) and corticosteroid-induced alkaline phosphatase (CIALP) genes and use those clones to determine the tissue source of CIALP, the kinetics of LALP and CIALP mRNA expression for glucocorticoid-treated dogs, and the correlation between LALP and CIALP transcript concentrations and isoenzyme activities. SAMPLE POPULATION: Tissues obtained from 7 dogs treated with prednisone (1 mg/kg, SC, q 24 h) for up to 32 days and 1 untreated (control) dog. PROCEDURE: Gene segments of LALP and CIALP were obtained by reverse transcription-polymerase chain reaction (RT-PCR) assay. The tissue source of CIALP and IALP mRNA was determined by northern blot analysis of tissues from 1 of the glucocorticoid-treated dogs. Hepatic tissues and serum samples were obtained from the 6 remaining glucocorticoid-treated dogs on days 0, 2, 5, 10, and 32 of prednisone treatment, and relative expression of LALP and CIALP mRNA was correlated with LALP and CIALP activity. RESULTS: A 2,246-base pair (bp) segment of canine LALP and a 1,338-bp segment of CIALP were cloned. Northern blot analysis revealed CIALP mRNA expression in hepatic tissues only after glucocorticoid treatment. Kinetics of LALP and CIALP mRNA expression in the liver of glucocorticoid-treated dogs paralleled liver and serum activities of LALP and CIALP. CONCLUSIONS AND CLINICAL RELEVANCE: The liver is the most likely source for CIALP in dogs. Analysis of kinetics of serum and hepatic LALP and CIALP mRNA suggests that after glucocorticoid treatment, both are regulated by modification of mRNA transcript concentrations, possibly through differing mechanisms.

Genomic sequence and cardiac expression of atrial natriuretic peptide in cats.

OBJECTIVE: To determine the nucleotide and amino acid sequence of atrial natriuretic peptide (ANP) in cats and its typical regions of cardiac expression. ANIMALS: 5 healthy adult mixed-breed cats. PROCEDURE: Total RNA was extracted from samples obtained from the left and right atrium, left and right ventricle, and interventricular septum of each cat. The RNA was used to produce cDNA for sequencing and northern blot analysis. Genomic DNA was extracted from feline blood samples. Polymerase chain reaction primers designed from consensus sequences of other species were used to clone and sequence the feline ANP gene. RESULTS: The feline ANP gene consists of 1,072 nucleotides. It consists of 3 exons (123, 327, and 12 nucleotides) separated by 2 introns (101 and 509 nucleotides). It has several typical features of eukaryotic genes and a putative steroid-response element located within the second intron. Preprohormone ANP consists of 153 amino acids. The amino acid sequence of the active form of feline ANP (ANP-30) is identical to that of equine, bovine, and ovine ANP-30 and differs from that of human, canine, and porcine ANP-28 only by 2 carboxy-terminal arginine residues. The ANP mRNA was detected only in the left and right atria. CONCLUSIONS AND CLINICAL RELEVANCE: The genetic and protein structure and principal regions of cardiac expression of feline ANP are similar to those of other species. Results of this study should be helpful in future studies on the natriuretic response in cats to diseases that affect cardiovascular function.

Evaluation of a continuous glucose monitoring system for use in dogs, cats, and horses.

OBJECTIVE: To evaluate a continuous glucose monitoring system (CGMS) for use in dogs, cats, and horses. DESIGN: Prospective clinical study. Animals-7 horses, 3 cats, and 4 dogs that were clinically normal and 1 horse, 2 cats, and 3 dogs with diabetes mellitus. PROCEDURE: Interstitial glucose concentrations were monitored and recorded every 5 minutes by use of a CGMS. Interstitial glucose concentrations were compared with whole blood glucose concentrations as determined by a point-of-care glucose meter. Interstitial glucose concentrations were also monitored in 2 clinically normal horses after oral and i.v. administration of glucose. RESULTS: There was a positive correlation between interstitial and whole blood glucose concentrations for clinically normal dogs, cats, and horses and those with diabetes mellitus. Events such as feeding, glucose or insulin administration, restraint, and transport to the clinic were recorded by the owner or clinician and could be identified on the graph and associated with time of occurrence. CONCLUSIONS AND CLINICAL RELEVANCE: Our data indicate that use of CGMS is valid for dogs, cats, and horses. This system alleviated the need for multiple blood samples and the stress associated with obtaining those samples. Because hospitalization was not required, information obtained from the CGMS provided a more accurate assessment of the animal's glucose concentrations for an extended period, compared with measurement of blood glucose concentrations. Use of the CGMS will promote the diagnostic and research potential of serial glucose monitoring.