[Adjustment of systolic and diastolic pressure in the left ventricle during acute changes in outflow resistance in a rat heart-lung preparation].
Knowledge of the course of active and passive pressure regulation of the heart is essential for characterizing its faculty of self-regulation. We therefore studied the adjustment of systolic and end-diastolic pressure development through the left ventricle of the heart-lung preparation of rat against an acutely enhanced outflow resistance. It had been determined previously, how and how long hemodynamic stability of the preparation could be reached and maintained under the given experimental conditions. On sudden enhancement of the outflow resistance from 60 to values of 100--160 mm Hg we observed a multiphasic response of the systolic and diastolic pressure whose extent and dynamics were proportional to load. The ability of the end-diastolic pressure to re-adjust was determined to be 60--68%. The results suggest a multifactorial mechanism of self-regulation.
D000818:Animals; D001794:Blood Pressure; D006321:Heart / Q000502:physiology*; D008297:Male; D009200:Myocardial Contraction; D051381:Rats; D014655:Vascular Resistance; D016276:Ventricular Function
Die Einstellung des systolischen und diastolischen Druckes des linken Ventrikels bei akuter Veränderung des Abstromwiderstandes am Herz-Lungen-Präparat der Ratte.