Hemodynamic and histomorphometric characteristics of dilated cardiomyopathy of Syrian hamsters (Bio TO-2 strain)

Abstract

The natural history of the disease of the dilated strain Bio TO-2 of cardiomyopathic hamsters (CMH) is not totally characterized. We investigated its hemodynamic and histomorphometric characteristics at 140, 180, 220, 260, and 300 days of age. Forty CMH and 40 controls were investigated (8 at each stage). Mean arterial pressure (MAP, carotid artery catheter) and cardiac output and femoral blood flow (CO, FBF, transit time method) were measured in anesthetized animals. Systemic (SVR) and femoral (FVR) vascular resistances were calculated. Atria, left and right ventricles (LV, RV), lungs, and liver were weighed. LV cavity area, LV and RV wall thicknesses and collagen densities were determined (computer-assisted image analyzer). Pulmonary and hepatic congestion were assessed (arbitrary scales). Compared with controls, MAP, CO and FBF were significantly lower in CMH throughout the study (on average: -22%, -34%, -33%, respectively), FVR was significantly increased (+15%), but SVR was not significantly modified. Concerning histomorphometric characteristics, differences between groups significantly increased with age for most variables: at 300 days, atria (+292%), RV (+13%), lungs (+44%), and liver (+23%) weights, LV cavity area (+130%), LV (+364%) and RV (+181%) collagen densities were significantly increased in CMH vs controls, whereas LV (-40%) and RV (-23%) wall thicknesses were significantly decreased. At 260 and 300 days, CMH showed significant pulmonary congestion without hepatic alteration. Bio TO-2 CMH progressively develop an alteration of cardiac function leading to decreased MAP and musculo-cutaneous blood flow associated with cardiac remodeling including atria hypertrophy and LV dilation, wall thinning and a rise in collagen density.

Chronic Istaroxime Improves Cardiac Function and Heart Rate Variability in Cardiomyopathic Hamsters

“…On the whole, the present results confirm previous findings on heart failure progression in Bio TO.2 hamsters [10][11][12][13][14]. Indeed, [7].…”

“…Animals were monitored by a veterinarian. Experiments were performed on Bio TO.2 Syrian hamsters, which represent a reproducible model of progressive cardiac hypertrophy, dilation and failure, that exhibits features resembling those of dilated cardiomyopathy in human [10][11][12][13][14]. Male Bio TO.2 and healthy Bio F1B Syrian hamsters were purchased from Bio Breeders Inc. (Watertown, MA, USA).…”

Activation of host tissue trophic factors through JAK-STAT3 signaling: a mechanism of mesenchymal stem cell-mediated cardiac repair

“…The ␦-sarcoglycan-null strain of TO2 hamster exhibits cardiac dysfunction between 1 and 2 mo of age and develops dilated cardiomyopathy (DCM), which leads to congestive heart failure resembling that seen in many patients (13,34,50). The ␦-sarcoglycan protein deficiency causes cell membrane fragility and permeability to Ca 2ϩ , inducing damages to myocytes, smooth muscle cells, and endothelial cells (20,30,49,55).…”

Cardiac and peripheral actions of growth hormone and its releasing peptides: Relevance for the treatment of cardiomyopathies

“…Genetically inherited cardiomyopathies in Syrian hamsters (CMH) may be classified according to their prominent feature, either ventricular dilatation in TO-2 [45] and MS200 [46], both derived from BIO 53.58, or hypertrophy in BIO 14.6 and derived strains including CHF-146, UM-X7.1 and CHF-147, a UM-X7.1 CMH subline [47,48].…”