Contribution of systemic blood pressure to myocardial remodeling in uremic rats.
Left ventricular hypertrophy with diffuse intermyocardiocytic fibrosis is a feature of uremia. The role of blood pressure and/or other cardiovascular uremic risk factors in cardiac remodeling is still uncertain. To determine the extent to which improvement of kidney function and the control of uremia-related risk factors are associated with a reduction of myocardial injury, we evaluated the effect of dietary protein restriction or the angiotensin-converting enzyme inhibitor lisinopril on cardiac structure in remnant kidney rats. One week after subtotal nephrectomy, Wistar rats were allocated to receive drinking water solution (group 1), 5 mg/kg per day lisinopril (group 2), or a low-protein diet (6%) (group 3) for 12 weeks. Group 2 and 3 showed a comparable efficacy in preventing the expected rise in creatininemia, urinary protein excretion, and glomerulosclerosis. However, hypertension development was prevented only in group 2. Groups 1 and 3 developed a significant (P < .01) increase in left ventricular weight (2.45 +/- 0.1 and 2.5 +/- 0.5 mg/g body wt, respectively) compared with group 2 (1.9 +/- 0.06 mg/g body wt). Cardiac hydroxyporline concentration was also lower in group 2 compared with group 1 (2.07 +/- 0.16 versus 2.73 +/- 0.17 mg/g left ventricular weight, P < .05) but not compared with group 3 (2.59 +/- 0.19 mg/g left ventricular weight). The effect of angiotensin-converting enzyme inhibition on left ventricular mass and intracardiac collagen content appeared to be dissociated from anemia, sympathetic activity, and hyperlipidemia. There was a close relationship between systolic pressure and left ventricular mass; however, no relationship between the degree of cardiac fibrosis and systolic pressure could be determined.(ABSTRACT TRUNCATED AT 250 WORDS)
Fabris
B
B
Institute of Medicina Clinica, Cattinara Hospital, University of Trieste, Italy.
Carretta
R
R
Fischetti
F
F
Candido
R
R
Calci
M
M
Castellano
M
M
Bardelli
M
M
Campanacci
L
L
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D004044:Dietary Proteins / Q000008:administration & dosage*; D006321:Heart / Q000187:drug effects* / Q000503:physiopathology; D006973:Hypertension / Q000209:etiology / Q000503:physiopathology* / Q000517:prevention & control; D017706:Lisinopril / Q000008:administration & dosage*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D014511:Uremia / Q000150:complications / Q000503:physiopathology*
D004044:Dietary Proteins; D017706:Lisinopril