scholarly journals Acupuncture Attenuates Renal Sympathetic Activity and Blood Pressure via Beta-Adrenergic Receptors in Spontaneously Hypertensive Rats

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Jing-Wen Yang ◽  
Yang Ye ◽  
Xue-Rui Wang ◽  
Fang Li ◽  
Ling-Yong Xiao ◽  
...  

The sympathetic nervous system, via epinephrine and norepinephrine, regulatesβ-adrenergic receptor (β-AR) expression, and renal sympathetic activation causes sustained increases in blood pressure by enhanced renin release. In this study, we aim to investigate the effect and underlying mechanism of acupuncture at Taichong (LR3) on renal sympathetic activity in spontaneously hypertensive rats. Unanesthetized rats were subject to daily acupuncture for 2 weeks. Mean blood pressure (MBP) and heart rate variability (HRV) were monitored at days 0, 7, and 14 by radiotelemetry. After euthanasia on the 14th day, blood and the kidneys were collected and subject to the following analyses. Epinephrine and norepinephrine were detected by ELISA. The expression ofβ-ARs was studied by western blotting and PCR. The renin content was analyzed by radioimmunoassay. 14-day acupuncture significantly attenuates the increase of MBP. The HRV indices, the standard deviation of all normal NN intervals (SDNN), and the ratio of the low-frequency component to the high-frequency component (LF/HF) were improved following acupuncture. Renal sympathetic activation induced upregulation of epinephrine, norepinephrine, and renin content were attenuated by acupuncture. In addition, acupuncture decreasedβ1-AR expression and improvedβ2-AR expression. These results indicated that acupuncture relieves the increased MBP via the regulation of renal sympathetic activity andβ-ARs.

2020 ◽  
Vol 318 (1) ◽  
pp. H124-H134 ◽  
Author(s):  
Zhi Geng ◽  
Chao Ye ◽  
Ying Tong ◽  
Feng Zhang ◽  
Ye-Bo Zhou ◽  
...  

Elabela (ELA) is a newly discovered peptide that acts as a novel endogenous ligand of angiotensin receptor-like 1 (APJ) receptor. This study was designed to evaluate the effects of ELA-21 in paraventricular nucleus (PVN) on blood pressure and sympathetic nerve activity in spontaneously hypertensive rats (SHR). Experiments were performed in male Wistar-Kyoto rats (WKY) and SHR. ELA expression was upregulated in PVN of SHR. PVN microinjection of ELA-21 increased renal sympathetic nerve activity (RSNA), mean arterial pressure (MAP), heart rate (HR), plasma norepinephrine, and arginine vasopressin (AVP) levels in SHR. Intravenous injection of ELA-21 significantly decreased MAP and HR in both WKY and SHR, but only induced a slight decrease in RSNA. APJ antagonist F13A in PVN abolished the effects of ELA-21 on RSNA, MAP and HR. Intravenous infusion of both ganglionic blocker hexamethonium and AVP V1a receptor antagonist SR49059 caused significant reduction in the effects of ELA-21 on RSNA, MAP and HR in SHR, while combined administration of hexamethonium and SR49059 abolished the effects of ELA-21. ELA-21 microinjection stimulated Akt and p85α subunit of phosphatidylinositol 3-kinase (PI3K) phosphorylation in PVN, whereas PI3K inhibitor LY294002 or Akt inhibitor MK-2206 almost abolished the effects of ELA-21 on RSNA, MAP, and HR. Chronic PVN infusion of ELA-21 induced sympathetic activation, hypertension, and AVP release accompanied with cardiovascular remodeling in normotensive WKY. In conclusion, ELA-21 in PVN induces exacerbated pressor and sympathoexcitatory effects in hypertensive rats via PI3K-Akt pathway. NEW & NOTEWORTHY We demonstrated that PVN microinjection of ELA-21 increases sympathetic nerve activity and blood pressure, which can be abolished by pretreatment of APJ antagonist. This is the first demonstration that central ELA can induce hypertension. The pressor effects in PVN are mediated by both sympathetic activation and vasopressin release via PI3K-Akt pathway. Our data confirm that ELA is upregulated in the PVN of SHR and so may be involved in the pressor and sympathoexcitatory effects in hypertension.


1987 ◽  
Vol 65 (4) ◽  
pp. 573-578 ◽  
Author(s):  
Esther A. Wilczynski ◽  
Frans H. H. Leenen

Spontaneously hypertensive rats were placed on a very low (9 μmol/g) or control (101 μmol/g) sodium diet at birth or 4 weeks of age. These diets were continued to 16 weeks of age, or at 10 weeks were increased from 9 to 26 or 101 μmol/g. Sodium restriction initiated up to 4 weeks of age and continued to 16 weeks of age severely retarded growth, prevented the development of hypertension, and reduced effective sympathetic activity as assessed by the response of blood pressure to ganglionic blockade. Only a small increase in sodium intake at 10 weeks of age (to 26 μmol/g or more) resulted in a marked increase in growth rate, an elevation of blood pressure, and a return of the response to ganglionic blockade towards normal. These data indicate that very severe sodium restriction must be continuous to maintain decreased sympathetic activity and normal blood pressure in spontaneously hypertensive rats. It appears that severe dietary sodium restriction suppresses one or more of the mechanisms involved in normal growth and development of hypertension in spontaneously hypertensive rats, but these mechanisms may still proceed once the sodium intake is increased.


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