DOCA‐salt hypertension impairs artery function in rat middle cerebral artery and parenchymal arterioles

Abstract

Objective Chronic hypertension induces detrimental changes in the structure and function of surface cerebral arteries. Very little is known about parenchymal arterioles (PAs), which perfuse distinct neuronal populations in the cortex and may play a role in cerebrovascular disorders. We investigated the effect of deoxycorticosterone acetate (DOCA)-salt induced hypertension on endothelial function and artery structure in PAs and middle cerebral arteries (MCAs). Methods Uninephrectomized male Sprague-Dawley rats were implanted with a subcutaneous pellet containing DOCA (150 mg/kg b.w.) and drank salt-water (1% NaCl and 0.2% KCl) for 4 weeks. Sham rats were uninephrectomized and drank tap water. Vasoreactivity and passive structure in the MCAs and the PAs were assessed by pressure myography. Results Both MCAs and PAs from DOCA-salt rats exhibited impaired endothelium dependent dilation (p<0.05). In the PAs, addition of NO and COX inhibitors enhanced dilation in DOCA-salt rats (p<0.05) suggesting that dysfunctional NO and COX-dependent signaling could contribute to impaired endothelium-mediated dilation. MCAs from DOCA-salt rats exhibited inward remodeling (p<0.05). Conclusions Hypertension-induced MCA remodeling coupled with impaired endothelium dependent dilation in both the MCAs and PAs may exacerbate the risk of cerebrovascular accidents and the associated morbidity and mortality.

ROS Suppression by Egg White Hydrolysate in DOCA-Salt Rats—An Alternative Tool against Vascular Dysfunction in Severe Hypertension

“…As we described above, hypertension in the DOCA-salt model impairs vasodilator responses [ 7 , 10 , 40 , 41 , 42 ], and these vascular effects are strongly related to systemic and locally promoted oxidative stress and inflammation [ 7 , 10 , 43 ]. However, until now, there have been no studies in this model evaluating the effect of dietary EWH supplementation on vascular damage.…”

Candesartan prevents arteriopathy progression in cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy model

“…Vessel lumen inner diameters (IDs) were tracked and recorded after 5 minutes at each pressure step by video microscopy using Myoview software (DMT). Passive distensibility was calculated as the percent change in ID from the original diameter (ID0, at 5 mmHg) at a given pressure (IDp): [(IDp -ID0)] / ID0] × 100 (%) (91)(92)(93).…”

Vasculo-Neuronal Coupling and Neurovascular Coupling at the Neurovascular Unit: Impact of Hypertension

“…Our group also reported increases in parenchymal arteriole tone in ex vivo brain slice preparations from mice infused with Ang II (600 ng/kg/min) for 28 days ( Diaz et al, 2019 ). In addition, DOCA-salt–induced hypertension has been shown to impair endothelium-dependent dilation via dysfunctional cyclooxygenase (COX) and NO signaling ( Matin et al, 2016 ).…”