Abstract 17726: Successful Anti-Hypertensive Effect of Carotid Body Denervation in Different Animal Models of Hypertension
The peripheral chemoreceptor reflex is sensitised in both the spontaneously hypertensive rat (SHR) and Goldblatt (2 kidney, 1 clip) renovascular model of hypertension. However, it is not known whether aberrant tonicity may be contributing to the development and maintenance of hypertension. Herein, we investigate the effect of carotid body denervation (CBD) in spontaneously hypertensive (SH) and Goldblatt (2 kidney 1 clip) rats.
Bilateral CBD was performed in two models of hypertension: (i) adult SH rats (12 weeks) with age- and sex matched Wistar rats; (ii) Wistar rats after partial occlusion of the left renal artery (Goldblatt) and sham operated age- and sex-matched Wistar rats. Arterial pressure was recorded telemetrically, and after baseline recordings (5 days) CBD or sham surgery was performed. Respiratory rate typically fell at week 1 following CBD (75±1 vs. 61±2 breaths/min) but recovered by week 3 (70±2 breaths/min). In adult SH rats, CBD lowered arterial pressure by ~20 mmHg. The development of arterial pressure in the Goldblatt rats was stunted after CBD; no change was observed in sham groups. In both SH and Goldblatt rats concurrent reductions in the low and very low spectral power of systolic blood pressure occurred suggesting systemic sympathoinhibition, which was confirmed by recording pronounced reductions in renal sympathetic nerve activity chronically (~55%). Baroreflex gain increased following CBD in SH and Goldblatt rats, but not in sham operated animals. CBD also reduced activation of T immune cells.
In summary, the carotid bodies play a major role in the maintenance of arterial pressure in adult SH and Goldblatt rats. These results are consistent a previous finding of the importance of the carotid body in the development of hypertension in young, pre-hypertensive SH rats. Our data support the idea that reducing carotid body afferent drive could provide a novel therapeutic treatment for human hypertension.
- © 2013 by American Heart Association, Inc.