Development of a sandwich enzyme-linked immunosorbent assay to detect and measure serum levels of canine ferritin.

We established a homologous sandwich enzyme-linked immunosorbent assay (ELISA) to measure serum levels of canine ferritin. Our assay uses a rabbit anti-canine heart ferritin polyclonal antibody, and canine heart ferritin as a standard. Serum ferritin concentration in healthy dogs (n=163) was 789 ± 284 ng/ml (mean ± standard deviation), a value higher than reported previously.

Matrix metalloproteinase-2 stimulates collagen-I expression through phosphorylation of focal adhesion kinase in rat cardiac fibroblasts.

Collagen-I is thought to be the main component of the extracellular matrix in cardiac fibrosis, the accumulation of which occurs with excessive activation of matrix metalloproteinase-2 (MMP-2). MMP-2 degrades the extracellular matrix; however, the relative importance of MMP-2 to collagen-I synthesis in cardiac fibroblasts remains unclear. We investigated whether extracellular activation of MMP-2 regulates collagen-I synthesis and phosphorylation of focal adhesion kinase (FAK) in rat cardiac fibroblasts.

Clinical implications of measurement of plasma atrial natriuretic peptide concentration in dogs with spontaneous heart disease.

Objective: To determine whether measurement of plasma atrial natriuretic peptide (ANP) concentration could be used to identify heart disease in dogs and to assess disease severity in affected dogs.

Design: Cross-sectional study.

Animals: 37 healthy dogs and 78 dogs with heart disease.

Myocardial injury-related changes in plasma NT-proBNP and ANP concentrations in a canine model of ischemic myocardial injury.

Serial changes in plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) and atrial natriuretic peptide (ANP) concentrations are unknown in dogs with myocardial injury. The time-course secretory responses between NT-proBNP and ANP or cardiac troponin-T (cTnT) related to myocardial infarction (MI) were investigated in this study. Six dogs were anaesthetised and the left anterior descending artery was ligated.

Spironolactone decreases isoproterenol-induced ventricular fibrosis and matrix metalloproteinase-2 in rats.

Although transregulation between the sympathetic nervous system and the renin-angiotensin-aldosterone system has been reported, it remains unclear whether sympathetic hyperactivity-induced matrix metalloproteinease (MMP) expression/activity and cardiac fibrosis are mediated by the mineralocorticoid receptor system. We investigated whether isoproterenol (ISO)-induced MMP expression/activity and cardiac fibrosis are mediated by spironolactone in rats. Male Wistar Kyoto rats were divided into 3 groups: control, ISO, and ISO combined with spironolactone (SPI).

The relationship between invasive hemodynamic measurements and tissue Doppler-derived myocardial velocity and acceleration during isovolumic relaxation in healthy dogs.

This study investigated the feasibility of using the values of tissue Doppler imaging (TDI)-derived myocardial velocity during isovolumic relaxation (V(IR)) and myocardial acceleration during isovolumic relaxation (ACC) obtained from the left ventricular (LV) free wall to evaluate LV relaxation in normal dogs. Seven dogs were anesthetized, and dobutamine or esmolol was infused at a rate of 5.0 and 10.

Differences in the duration of diuretic effects and impact on the renin-angiotensin-aldosterone system of furosemide in healthy dogs.

Our aim was to investigate the differences in the duration of diuretic effects and impact on the renin-angiotensin-aldosterone (RAA) system of furosemide as a model of short- and long-acting loop diuretics. Anesthetized dogs (n=6) were randomized into placebo, intravenous bolus administration (IB) and chronic rate infusion (CRI) groups. This study was conducted with a crossover study.

Acute cardiac volume load-related changes in plasma atrial natriuretic peptide and N-terminal pro-B-type natriuretic peptide concentrations in healthy dogs.

Plasma atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) have been used for the diagnosis of heart disease. The aim of the study was to investigate differences in secretory responses of plasma ANP and N-terminal proBNP (NT-proBNP) concentrations related to acute changes in preload. Six dogs were anaesthetised and infused intravenously with Ringer's solution (90-100mL/kg/h) for 60 min.

Assessment of diuretic effects and changes in plasma aldosterone concentration following oral administration of a single dose of furosemide or azosemide in healthy dogs.

Objective: To determine the diuretic effects and changes in plasma aldosterone concentration (PAC) following oral administration of a single dose of furosemide or azosemide in healthy dogs.

Animals: 8 mixed-breed dogs.

Procedures: A single dose of furosemide (2 mg/kg), azosemide (1, 5, or 10 mg/kg), or placebo (bifidobacterium [1 mg/kg]) was administered orally (in random order at 7-day intervals) to each dog (5 treatments/dog).

Assessing diastolic function with Doppler echocardiography using a novel index: ratio of the transmitral early diastolic velocity to pulmonary diastolic velocity.

We developed a novel index to assess left ventricular (LV) relaxation as the ratio of transmitral early diastolic velocity to pulmonary diastolic velocity (E/D ratio). Mixed breed dogs (n=7) were anesthetized and their respiration was controlled. A 3.

Relationships between velocities of pulmonary venous flow and plasma concentrations of atrial natriuretic peptide in healthy dogs.

Objective: To investigate the relationship between velocities of pulmonary venous flow (PVF) and plasma concentrations of atrial natriuretic peptide (ANP) in healthy dogs.

Animals: 7 healthy Beagles.

Procedures: Dogs were anesthetized, intubated, and positioned in left lateral recumbency.

Volume loading-related changes in tissue Doppler images derived from the tricuspid valve annulus in dogs.

Objective: To investigate the relationship between preload and tricuspid valve annulus-derived tissue Doppler imaging (TDI) as an index of right ventricular (RV) filling in dogs.

Animals: 7 Beagles.

Procedures: Peak systolic RV pressure and RV end-diastolic pressure (RVEDP) were measured in anesthetized dogs.

Comparison of the myocardial performance index derived by use of pulsed Doppler echocardiography and tissue Doppler imaging in dogs with volume overload.

Objective: To investigate the relationship between the myocardial performance index (MPI) determined by use of pulsed Doppler (PD) echocardiography and tissue Doppler imaging (TDI) in the response to volume overload-related changes in left ventricle (LV) performance.

Animals: 7 male Beagles.

Procedures: Dogs were anesthetized and intubated.

Effects of oral administration of furosemide and torsemide in healthy dogs.

Objective: To investigate the diuretic effects, tolerability, and adverse effects of furosemide and torsemide after short- and long-term administration in healthy dogs.

Animals: 8 mixed-breed dogs.

Procedures: In a crossover study, furosemide (2 mg/kg), torsemide (0.

Assessment of longitudinal tissue Doppler imaging of the left ventricular septum and free wall as an indicator of left ventricular systolic function in dogs.

Objective: To evaluate tissue Doppler imaging (TDI) of the left ventricular (LV) free wall (FW) and ventricular septum (VS) as an indicator of LV systolic function in dogs.

Animals: 7 healthy Beagles.

Procedures: Doses of dobutamine (5 and 10 microg/kg/min) and esmolol (50 and 100 microg/kg/min) were infused into the LV of each dog.

Effect of isoflurane anesthesia on hemodynamics following the administration of an angiotensin-converting enzyme inhibitor in cats.

The objective of this study was to evaluate the hemodynamics of the anesthetic isoflurane in healthy cats given angiotensin-converting enzyme inhibitor (ACEI). The 7 healthy young cats and 3 old cats were received placebo or enalapril 0.5 mg/kg orally.

Relationship between tissue Doppler-derived RV systolic function and invasive hemodynamic measurements.

Tissue Doppler imaging (TDI) is effective in assessing right ventricular (RV) function, but the relationship between invasive measurements and RV-TDI remains unclear. We investigated the RV systolic function by using the TDI-derived systolic myocardial (Sa) velocity and myocardial performance index (MPI). Beagles (n = 7) were anesthetized in the right lateral recumbent position.