EFFECT OF CHRONIC RENAL-INSUFFICIENCY ON THE FUNCTION AND METABOLIC PARAMETERS OF THE ISOLATED RAT-HEART

Chronic renal insufficiency (CRI) is often associated with cardiovascu lar disease; however, its underlying mechanisms are not completely und erstood. Therefore, in the present study, myocardial functions and met abolic changes were investigated using an animal model of CRI in subto tally nephrectomized rats. In addition, some other parameters, conside red risk factors of cardiovascular diseases, were determined. Subtotal nephrectomy led to an elevation in blood pressure (144+/-2.8 vs 114+/ -2.5 mm Hg), left ventricular hypertrophy (290+/-12 vs 200+/-40 mg/100 g b.w.), hypertriglyceridaemia (2.96+/-0.31 vs 0.77+/-0.07 mmol/l), a nd impaired glucose tolerance (AUC 836+/-12.4 vs 804+/-10.4 mmol . l(- 1). 120 min). Isolated perfused hearts of uraemic rats exhibited dimin ished basal functions (coronary and aortic flow, stroke volume) by 20- 30 % compared with the controls. Interestingly, the tolerance of isola ted heart to global 20-min no-flow ischaemia was improved in uraemic r ats. The most marked differences in heart function recovery during rep erfusion concerned aortic flow (90+/-2.3 vs 66+/-10 %) and stroke volu me (97+/-2.7 vs 68+/-5.6 % of pre-ischaemic values). Pre-ischaemic myo cardial glycogen content was distinctly increased (by 50 %) in uraemic rats compared with the controls.