Dynamics of the hypertrophied left ventricle in the rat. Effects of physical training and chronic pressure load.
Left ventricular hypertrophy of about 40% was produced in rats by narrowing one renal artery (Goldblatt II) and of about 6% by swimming-training for 2 hours a day for 14 weeks. The dynamics of the hypertrophied ventricles were investigated by means of the isovolumic systolic and diastolic pressure-volume relations, the stress development during afterloaded and isovolumic contractions, and the force-velocity relation. The following results were obtained: The performance of the whole hypertrophied ventricle is increased. The developed stress and the maximum rate of stress development are enhanced, probably as a consequence of the increased density of the contractile proteins. The maximum shortening velocity can be reduced at the same time.
D000222:Adaptation, Physiological; D000818:Animals; D001794:Blood Pressure; D006332:Cardiomegaly / Q000503:physiopathology*; D002908:Chronic Disease; D006973:Hypertension / Q000503:physiopathology; D009200:Myocardial Contraction; D005082:Physical Exertion; D051381:Rats; D013550:Swimming; D016276:Ventricular Function