Abstract 17485: Carotid Body Denervation Markedly Improves Survival of Hypertensive Heart Failure in Rats
Introduction: Hypertension is a major cause of heart failure. Since carotid body denervation (CBD) is known to inhibit excessive sympathoexcitation in animal models of hypertension and/or heart failure, we hypothesized that the CBD-induced sympathoinhibition improves the survival in Dahl salt-sensitive rats with high-salt diet, as an animal model of hypertensive heart failure.
Methods: Dahl salt-sensitive rats with high-salt diet (8% NaCl) were randomized into CBD (N=14) and sham operated (N=18) groups. At 7 weeks of age, we removed the tissues around the carotid bifurcation and established CBD. Echocardiograms and 24-hour urinary norepinephrine (uNE) excretion as parameters of sympathoexcitation were assessed in every week. In some rats, we telemetrically recorded blood pressure. We conducted detailed physiological and histological analyses at 16 weeks. Finally, we compared the survival rate between 2 groups.
Results: At 11 weeks of age, CBD did not alter blood pressure (162±15 vs. 169±12 mmHg, NS) or uNE (0.9±0.5 vs. 1.1±0.5 μg/day, NS, Fig 1). In contrast, at 14 weeks of age, CBD significantly reduced the development of hypertension (209±14 vs. 228±11 mmHg, p<0.05) and uNE (1.0±0.6 vs. 2.0±0.4 μg/day, p<0.05, Fig 1). CBD prevented the loss of body weight (311±23 vs. 286±50 g, p<0.05), and tended to reduce biventricular weight (4.6±0.4 vs. 5.0±0.2 g/kg) as well as lung weight (4.8±0.5 vs. 6.1±1.1 g/kg) at 16 weeks of age. Furthermore, CBD markedly improved the survival rate (100 vs. 45 %, p=0.024, Fig. 2). Postmortem studies indicated that those rats died of heart failure.
Conclusions: CBD significantly inhibited the sympathoexcitation, attenuated the development of hypertension and improved survival in Dahl salt-sensitive rats. CBD could be a new therapeutic strategy for hypertensive heart failure.
Author Disclosures: K. Fujii: None. K. Saku: None. T. Kishi: None. T. Takehara: None. T. Akashi: None. Y. Oga: None. A. Nishizaki: None. T. Ide: None. K. Sunagawa: None.
- © 2014 by American Heart Association, Inc.