Effect of telmisartan on preexistent cardiac and renal lesions in spontaneously hypertensive mature rats.

Fifteen adult male spontaneously hypertensive rats (one year old) (SHR) were separated into three groups (n=5 each) during 15 weeks as follows: initial control group (IC); final control group (FC); and telmisartan group (T) (1.2 mg/kg/day of telmisartan). Serum and urinary creatinine and proteinuria were not different comparing untreated and telmisartan-treated SHRs. FC rats showed a continuous BP increase during the study while T rats reached the 15th week with a significantly low BP. The LV mass index was significantly smaller in the T group than in the FC group, as was the glomerular hypertrophy. The cardiomyocyte nuclei density per area and the cardiomyocyte mean cross-sectional area were smaller in the T group than in both the IC and FC groups. Intramyocardial artery densities (per area and per volume) were greater in the T group than in untreated SHRs, but myocardial fibrosis was reduced. In conclusion, telmisartan monotherapy effects on BP and also on the hypertension target organs, heart and kidney, are favorable. Telmisartan is able to attenuate SHR cardiomyocyte and glomerular hypertrophies, and myocardial reactive fibrosis as well. It also is favorable to the intramyocardial microcirculation.