Afferent Renal Denervation Attenuates Sympathetic Overactivation From the Paraventricular Nucleus in Spontaneously Hypertensive Rats.

BACKGROUND: The effectiveness of renal denervation (RDN) in reducing blood pressure and systemic sympathetic activity in hypertensive patients has been established. However, the underlying central mechanism remains unknown. This study aimed to investigate the role of RDN in regulating cardiovascular function via the central renin-angiotensin system (RAS) pathway. METHODS: Ten-week-old spontaneously hypertensive rats (SHR) were subjected to selective afferent renal denervation (ADN) using capsaicin solution. We hypothesized that ADN would effectively reduce blood pressure and rebalance the RAS component of the paraventricular nucleus (PVN) in SHR. RESULTS: The experimental results show that the ADN group exhibited significantly lower blood pressure, reduced systemic sympathetic activity, decreased chronic neuronal activation marker C-FOS expression in the PVN, and improved arterial baroreflex function, compared with the Sham group. Furthermore, ACE and AT1 protein expression was reduced while ACE2 and MAS protein expression was increased in the PVN of SHR after ADN. CONCLUSIONS: These findings suggest that RDN may exert these beneficial effects through modulating the central RAS pathway.

Effects of Exercise Training on PPARß/δ Expression in Skeletal Muscle of Rats with Spontaneous Hypertension.

PURPOSE: This study aimed to identify the relationship and mechanism between skeletal muscle peroxisome proliferator-activated receptor ß/δ (PPARß/δ) and spontaneous hypertension. METHODS: Rats were divided into four groups ( n = 10): spontaneous hypertensive rats exercise group (SHR-E), spontaneous hypertensive rats sedentary group (SHR-S), Wistar-Kyoto control rats exercise group (WKY-E), and Wistar-Kyoto control rats sedentary group (WKY-S). Although the sedentary groups were placed on the treadmill without moving during the training sessions, the exercise groups were forced to run on a treadmill for 8 wk, 1 h·d -1 , 5 d·wk -1 . After training, the density and area of gastrocnemius microvessels were observed. PPARß/δ, vascular endothelial growth factor A (VEGFA), superoxide dismutase 2 (SOD-2), and nitric oxide synthase in gastrocnemius were measured by real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot. RESULTS: Except the sixth week of age, the systolic blood pressure of SHR-S was significantly higher than that of WKY-S at all time periods. Exercise significantly reduced systolic blood pressure in SHR rats. Compared with the SHR-S group, the WKY-S group had significantly higher PPARß/δ protein level and density of skeletal muscle microvessels. Eight weeks of exercise increased the PPARß/δ, SOD-2, VEGFA, and microvessel density and area in the skeletal muscle of SHR. CONCLUSIONS: Exercise training promoted PPARß/δ mRNA and protein-level expression of PPARß/δ, SOD-2 and VEGFA in skeletal muscle, thus increasing the density and area of skeletal muscle blood vessels. These regulations contribute to the reduction of peripheral vascular resistance. This may be a potential mechanism of exercise to reduce blood pressure.

Effect of Exercise Prescription Implementation Rate on Cardiovascular Events.

BACKGROUND: Exercise prescription of cardiac rehabilitation (CR) is vital in patients with cardiovascular diseases (CVDs) and those carrying high risk for CVDs. However, the relation between the implementation rate of exercise prescription and cardiovascular events (CVEs) is unclear. DESIGN AND METHODS: In this retrospective study, using the administration data from the Rehabilitation Center in a hospital, patients aged ≥18 years with CVDs were consecutively enrolled from November 2018 to May 2021. Patients were divided into the high execution group (HEG) and low execution group (LEG) depending on whether they completed more than half the time of the exercise prescriptions. Baseline characteristics, ultrasonic cardiogram, cardiopulmonary exercise test, follow-up data, and CVEs were collected. RESULTS: The mean age of the 197 CR patients was 61.8 ± 13.7 years and the mean follow-up duration was 10.9 ± 4.2 months. Among them, 15 patients suffered CVEs: 4 in the HEG and 11 in the LEG. The incidence of CVEs showed significant differences between HEG and LEG (chi-square test). Free-event survival analysis using Kaplan-Meier survival plots showed that patients in LEG had poor survival. Cox proportional hazards regression analysis revealed that the prescription implementation rate was an independent predictor of CVEs. CONCLUSIONS: Our study suggested a significant effect of exercise prescription execution rate on the occurrence of CVEs. Further, the HEG of exercise prescription was associated with lower CVDs.