Early Structural Changes of Aortic Wall in Sinoaortic‐denervated Rats

Abstract

1. The present work was designed to observe the early structural changes in the aortic wall in Sprague-Dawley rats 1, 2 and 4 weeks after sinoaortic denervation (SAD). 2. Rats were examined 1, 2 and 4 weeks after SAD. Blood pressure (BP) was recorded in the conscious state. The thoracic aortas were taken for investigations, including: light microscopy, electron microscopy, immunohistochemistry and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labelling (TUNEL). 3. Blood pressure variability (BPV) was significantly increased in the SAD groups 1, 2 and 4 after the operation when compared with the sham-operated ones. 4. Two weeks after SAD the percentage proportion of smooth muscle cell density (SMC%) was obviously increased. 5. Four weeks after SAD: the SMC%, percentage proportion of collagen density (CD%) and aortic wall thickness (WT) were obviously increased with vascular smooth muscle cells blebbing concomitantly. Endothelial cells showed degenerative changes and swelling with blebbing of the cell membrane and increased condensation of peripheral nuclear chromatin and cytoplasmic vacuolization. It was also found that the number of apoptotic endothelial cells was increased and expression of eNOS was reduced. 6. This is the first study that shows the time-course of aortic wall and endothelial cell changes induced by SAD. Increased BPV might be the priming factor in the development of organ damage induced by SAD.

Baroreflex and Cerebral Autoregulation Are Inversely Correlated

“…Experimental data are available showing that baroreflex impairment can cause atheroma through inflammation and endothelial cell changes. 7, 8 Improvement of baroreflex function after low-dose ketanserin has prevented the development of atherosclerosis in rats and rabbits. This effect was independent of ABP lowering.…”

“…5, 6 Also, it is possible that impaired BRS can accelerate atherosclerosis through inflammation and endothelial cell changes. 7, 8 Baroreflex and Cerebral Autoregulation of ABP was achieved using a servo-controlled finger plethysmograph (Finapres, Ohmeda, CO, USA for patients with carotid stenosis; and Nexfin, BMI for volunteers). Mean ABP and mean CBF velocities (CBFV) in the MCA were recorded over 10-20 min.…”

Arterial baroreflex function is an important determinant of acute cerebral ischemia in rats with middle cerebral artery occlusion

“…SAD was performed in SD rats according to the procedure described by Krieger (1964) with minor modifications (Shen et al, 2006). Briefly, rats were anesthetized with a mixture of ketamine and diazepam (i.p.)…”

Circadian expression of clock genes and angiotensin II type 1 receptors in suprachiasmatic nuclei of sinoaortic-denervated rats

“…In hypertensive rats, the target organ damage correlates negatively with ABR function [10,25] . Interruption of ABR by sinoaortic denervation induced aortic and cardiac hypertrophy independent of the mean level of blood pressure [26][27][28] . In the present study, it was found that dysfunction of the ABR attenuated the circadian expression of clock genes in the SCN.…”