EFFECTS OF RENOVASCULAR HYPERTENSION ON MYOCARDIAL PROTEIN-PATTERNS -ANALYSIS BY COMPUTER-ASSISTED 2-DIMENSIONAL GEL-ELECTROPHORESIS

Hypertensive heart disease caused by renovascular hypertension reflect s the response of the heart to an increased afterload and neurohormona l stimulation. We hypothesized that in this condition the composition of the myocardial proteins of rats was altered. To identify yet unknow n quantitative and qualitative differences in myocardial proteins in r enovascular hypertensive heart disease, we analyzed protein patterns b y computer-assisted two-dimensional polyacrylamide large gel electroph oresis. Renovascular hypertension was induced by placing a silver clip on the left renal artery in 9-week-old rat siblings. Sham-operated an imals served as controls. Systolic blood pressure (197 +/- 19 mm Hg) a nd heart/body weight ratios (0.36 +/- 0.04%) were significantly increa sed in the hypertensive animals. Twenty protein patterns from the left ventricle of five hypertensive and five control rats were compared. T he molecular mass and isoelectric point (pl) of proteins spots ranging from 13 to 100 kDa and from 4.5 to 8.5, respectively, were determined using marker proteins. In total, 761 +/- 88 protein spots were resolv ed in all twenty gels. For the quantitative data analysis a univariate (Mann-Whitney test) as well as a multivariate statistical approach (c orrespondence analysis) were applied. Only one myocardial protein spot (molecular mass = 41.3 kDa; pI = 6.3) was decreased by more than twof old (p < 0.05) in renovascular hypertension. The vast majority of spot s did not indicate a significant alteration of intensity. Left ventric ular hypertrophy in early renovascular hypertension induces a form of myocardial hypertrophy that conserves the naturally occurring protein expression pattern.