S. Roysommuti et al., Lifetime treatment with captopril improves renal function in spontaneouslyhypertensive rats., CLIN EXP HY, 21(8), 1999, pp. 1315-1325
Lifetime treatment with captopril prevents the development of hypertension
in spontaneously hypertensive rats (SI-IR). This study tests the hypothesis
that compared to untreated hypertensive SHR, captopril-treated SHR display
similar diuretic and natriuretic responses to an isotonic saline infusion
despite significantly lower arterial pressure. Eight-week-old, male SHR wer
e instrumented with femoral arterial, venous, and bladder catheters. Forty-
eight hours later, each rat was infused intravenously with an isotonic sali
ne load (5% of body weight; 0.5 ml/min). Lifetime captopril-treated SHR and
untreated control SHR displayed nearly identical natriuretic and diuretic
responses to the saline infusion. Thus, although lifetime captopril treatme
nt significantly reduces mean arterial pressure in SHR, renal excretory res
ponses appear to be unaltered. Moreover, histological examination of the ki
dneys of the lifetime captopril-treated SHR did not reveal significant stru
ctural damage in the kidneys at either 8 weeks of age or at 12 months of ag
e. Together, the data suggest that lifetime captopril treatment does not ad
versely affect renal function and structure in SHR.