Angiotensin converting enzyme inhibition improves cerebrovascular control during exercise in male rats with heart failure

We investigated the effects of chronic (-7 weeks) treatment with the angiotensin converting enzyme (ACE) inhibitor Captopril in rats with heart failure with reduced ejection fraction (HF-rEF) on brain blood flow (BF; radiolabeled microspheres) at rest and during submaximal exercise. We hypothesized that middle cerebral, posterior cerebral, and cerebellar BF during submaximal exercise (20 m/min, 5% incline) would be reduced in rats with HF-rEF (n = 10) compared to healthy (SHAM, n = 10) controls and HF-rEF rats chronically treated with Captopril (HF-rEF + Cap., n = 20). During submaximal exercise middle cerebral (HF-rEF + Cap.: 274 +/- 12; HFrEF: 234 +/- 23; SHAM: 248 +/- 24 ml/min/100 g) and cerebellar (HF-rEF + Cap.: 222 +/- 14; HF-rEF: 243 +/- 22; SHAM: 214 +/- 23 ml/min/100 g) BF increased from rest in all groups with no difference among groups (P > 0.24). Posterior cerebral BF increased from rest in all groups but was lower than SHAM (394 +/- 46 ml/min/100 g; P = 0.03) in HF-rEF (298 +/- 19 ml/min/100 g) but not HF-rEF + Cap. (356 +/- 18 ml/min/100 g; P = 0.14), supporting the concept that ACE inhibition in HF-rEF elevates brain BF increases, at least to the posterior cerebral region, during moderate intensity exercise/physical activity.

Automated summary

The study investigated the effects of chronic treatment with ACE inhibitor Captopril on brain blood flow in rats with HF-rEF during submaximal exercise. The results showed that middle cerebral and cerebellar blood flow increased during exercise in both HF-rEF and HF-rEF + Cap. groups, with no significant difference compared to the SHAM group, while posterior cerebral blood flow was lower in HF-rEF compared to SHAM.