The nucleus tractus solitarius (NTS) is the primary brain region for receiving and integrating cardiovascular afferent signals. It plays a crucial role in maintaining balance of autonomic nervous system and regulating blood pressure through cardiovascular reflexes. Neurons within the NTS form complex synaptic connections and interact reciprocally with other brain regions. The NTS regulates autonomic nervous system activity and arterial blood pressure through modulating baroreflex, sympathetic nerve activity, renin-angiotensin-aldosterone system, and oxidative stress. Dysfunctions in NTS activity may contribute to hypertension. Understanding the NTS' role in centrally regulating blood pressure and alterations of neurotransmission or signaling pathways in the NTS may provide rationale for new therapeutic strategies of prevention and treatment. This review summarizes the research findings on autonomic nervous system regulation and arterial blood pressure control by NTS, as well as unresolved questions, in order to provide reference for future investigation.
Solitary Nucleus/physiopathology* ; Hypertension/physiopathology* ; Humans ; Animals ; Autonomic Nervous System/physiopathology* ; Blood Pressure/physiology* ; Baroreflex/physiology* ; Renin-Angiotensin System/physiology* ; Sympathetic Nervous System/physiology*

OBJECTIVE: To assess the efficacy of Qingda Granule (QDG) in ameliorating hypertension-induced cardiac damage and investigate the underlying mechanisms involved. METHODS: Twenty spontaneously hypertensive rats (SHRs) were used to develope a hypertension-induced cardiac damage model. Another 10 Wistar Kyoto (WKY) rats were used as normotension group. Rats were administrated intragastrically QDG [0.9 g/(kg•d)] or an equivalent volume of pure water for 8 weeks. Blood pressure, histopathological changes, cardiac function, levels of oxidative stress and inflammatory response markers were measured. Furthermore, to gain insights into the potential mechanisms underlying the protective effects of QDG against hypertension-induced cardiac injury, a network pharmacology study was conducted. Predicted results were validated by Western blot, radioimmunoassay immunohistochemistry and quantitative polymerase chain reaction, respectively. RESULTS: The administration of QDG resulted in a significant decrease in blood pressure levels in SHRs (P<0.01). Histological examinations, including hematoxylin-eosin staining and Masson trichrome staining revealed that QDG effectively attenuated hypertension-induced cardiac damage. Furthermore, echocardiography demonstrated that QDG improved hypertension-associated cardiac dysfunction. Enzyme-linked immunosorbent assay and colorimetric method indicated that QDG significantly reduced oxidative stress and inflammatory response levels in both myocardial tissue and serum (P<0.01). CONCLUSIONS Both network pharmacology and experimental investigations confirmed that QDG exerted its beneficial effects in decreasing hypertension-induced cardiac damage by regulating the angiotensin converting enzyme (ACE)/angiotensin II (Ang II)/Ang II receptor type 1 axis and ACE/Ang II/Ang II receptor type 2 axis.
Animals ; Drugs, Chinese Herbal/therapeutic use* ; Hypertension/pathology* ; Renin-Angiotensin System/drug effects* ; Rats, Inbred SHR ; Oxidative Stress/drug effects* ; Male ; Rats, Inbred WKY ; Blood Pressure/drug effects* ; Myocardium/pathology* ; Rats ; Inflammation/pathology*

OBJECTIVE: To investigate the correlation between the carotid artery plaque and the change of plasma aldosterone level related indexes during captopril challenge test. METHODS: The patients with hypertension were enrolled as research objects and the captopril challenge test were carried out when they were hospitalized to screen the cause of hypertension. There were intact carotid artery duplex ultrasonography diagnostic data in them (83 cases). They were divided into the plaque group(57 cases) with carotid artery plaque and no plaque group( 26 cases) without carotid artery plaque according to the carotid artery duplex ultrasonography diagnostic data. The correlation between the carotid artery plaque and the changes of aldosterone concentration, renin activity and aldosterone to renin activity ratio(ARR) in two groups were analyzed. RESULTS: The detection rate of carotid artery plaque was 68.67%. Compare with no plaque group, the patients in plaque group were elder and the level of apolipoprotein A1,(APOA1) was lower (all P＜0.05). The ARR difference value before and after captopril challenge test was lower ( P＜0.05).The aldosterone difference value and the renin activity difference value before and after captopril challenge test were higher in plaque group (all P＜0.05).The aldosterone difference value and the renin activity difference value were positive in plaque group and were negative in no plaque group. The difference value of the ARR was negative in plaque group and was positive in no plaque group. Logistic regression analysis showed that the age, the difference value of ARR and the aldosterone before and after captopril challenge test could be associated independently with carotid artery plaque occurrence after excluding gender difference and other factors. CONCLUSION The detection rate of carotid artery plaque was high among hospitalized patients with hypertension, the difference value of ARR and the aldosterone before and after captopril challenge test could be associated independently with carotid artery plaque occurrence.
Aldosterone ; blood ; Angiotensin-Converting Enzyme Inhibitors ; pharmacology ; Captopril ; pharmacology ; Carotid Stenosis ; drug therapy ; Humans ; Hypertension ; drug therapy ; Inpatients ; Renin

Aortoiliac occlusive disease (AIOD), especially proximal to the transplant artery, in kidney transplant patient activates the renin-angiotensin-aldosterone system by limiting graft renal perfusion and causes symptoms that can occur with transplant renal artery stenosis (TRAS) such as refractory hypertension, water retention, and graft renal dysfunction. Immediate clinical suspicion is difficult due to the nature of the progressive disease unlike TRAS. Herein, we present an interesting case of bilateral common iliac artery occlusion (AIOD, TASC II, type C) that manifested as uncontrolled blood pressure and decreased allograft function in a patient who had kidney transplant 17 years ago. The patient was successfully diagnosed with duplex scan, ankle-brachial index (ABI) and computed tomography angiography and treated with percutaneous luminal angioplasty and stent graft insertion.
Allografts ; Angiography ; Angioplasty ; Ankle Brachial Index ; Arteries ; Blood Pressure ; Blood Vessel Prosthesis ; Humans ; Hypertension ; Iliac Artery ; Kidney Transplantation ; Kidney ; Perfusion ; Phenobarbital ; Renal Artery Obstruction ; Renin-Angiotensin System ; Transplants ; Water

OBJECTIVE: To study the effect of 6-week intensive training on renal function in rats and the mechanism of exercise-induced proteinuria. METHODS: Thirty-six male SD rats, aged 6 weeks, were divided into two groups, including a control group(C,=12)and an overtraining group(M,=24). After the rats adapted to feeding for 4 d, group C did not carry out any exercise, and the M group did 6-week of increasing load swimming, 6 days a week, once a day. Started with the load of 1%weight at the beginning of the 4 week,and gradually increased (to 6% weight). Took a single urine from both groups 30 min after the end of the training. Blood was taken from the main ventral vein, and the bilateral kidneys were to be tested. The levels of tested urine protein, microalbumin and neutrophil gelatinase associated lipocalin(NGAL) was determined by using enzyme linked immunosorbent assaytest. The content of urine creatinine was tested with alkaline picric acid method,. The serum levels of colorimetric method to determine serum creatinine and urea nitrogen were determined by colorimetric method. The expression of Nephrin in renal tissue was detected by Western blot and the radioimmunoassay was used to test serum testosterone, corticosterone and renin-angiotensin system related index. RESULTS: Compared with group C, the serum testosterone/cortisone(T/C) of group M was decreased significantly (<0.01). The urine total protein(TP), microalbumin (mAlb), microalbumin/creatinine (mAlb/CRE), NGAL, blood urea nitrogen (BUN) and serum creatinine(SCr) were increased significantly (<0.01). The abnormality of glomerular structure was obvious, and the paller scores were higher. The protein expression of Nephrin was obviously down decreased (<0.01). The renin activity (Ra) and angiotension Ⅱ (Ang Ⅱ) in renal and circulating blood were decreased significantly (<0.01). CONCLUSIONS The effects of 6-week intensive training on renal function in rats and the mechanism of exercise-induced proteinuria may be that overtraining can induce the continuous excitation of Reninrenin activity in renal and circulating blood, down-regulated the expression of Nephrin, lead to abnormality of renal structure and function, and proteinuria.
Animals ; Blood Urea Nitrogen ; Corticosterone ; blood ; Creatinine ; blood ; Kidney ; physiopathology ; Male ; Membrane Proteins ; metabolism ; Physical Conditioning, Animal ; adverse effects ; Proteinuria ; Rats ; Rats, Sprague-Dawley ; Renin-Angiotensin System ; Testosterone ; blood

Nephrotic syndrome in the first year of life, characterized by renal dysfunction and proteinuria, is associated with a heterogeneous group of disorders. These disorders are often related to genetic mutations, but the syndrome can also be caused by a variety of other diseases. We report an infant with nephrotic syndrome associated with a neuroblastoma. A 6-month-old girl was admitted with a 10% weight loss over 10 days and nephrotic-range proteinuria. She was ill-looking, and her blood pressure was higher than normal for her age. Her cystatin-C glomerular filtration rate was decreased, and levels of plasma renin, aldosterone, and catecholamines were elevated. Renal ultrasonography and abdominal computed tomography showed a retroperitoneal prevertebral mass encasing both renal arteries and the left renal vein. The mass was partially resected laparoscopically, and the pathologic diagnosis was neuroblastoma. Findings on a simultaneous renal biopsy were unremarkable. The patient was treated with chemotherapy and several anti-hypertensive drugs, including an alpha blocker. Two months later, the mass had decreased in size and the proteinuria and hypertension were gradually improving. In an infant with abnormal renin-angiotensin system activation, severe hypertension, and nephrotic-range proteinuria, neuroblastoma can be considered in the differential diagnosis.
Aldosterone ; Antihypertensive Agents ; Biopsy ; Blood Pressure ; Catecholamines ; Diagnosis ; Diagnosis, Differential ; Drug Therapy ; Female ; Glomerular Filtration Rate ; Humans ; Hypertension ; Infant ; Nephrotic Syndrome ; Neuroblastoma ; Plasma ; Proteinuria ; Renal Artery ; Renal Veins ; Renin ; Renin-Angiotensin System ; Ultrasonography ; Weight Loss

Fructose intake has increased dramatically over the past century and the upward trend has continued until recently. Increasing evidence suggests that the excessive intake of fructose induces salt-sensitive hypertension. While the underlying mechanism is complex, the kidney likely plays a major role. This review will highlight recent advances in the renal mechanisms of fructose-induced salt-sensitive hypertension, including (pro)renin receptor-dependent activation of intrarenal renin-angiotensin system, increased nephron Na transport activity via sodium/hydrogen exchanger 3 and Na/K/2Cl cotransporter, increased renal uric acid production, decreased renal nitric oxide production, and increased renal reactive oxygen species production, and suggest actions based on these mechanisms that have therapeutic implications.
Blood Pressure ; Fructose ; adverse effects ; Humans ; Hypertension ; chemically induced ; physiopathology ; Kidney ; physiopathology ; Nitric Oxide ; metabolism ; Reactive Oxygen Species ; metabolism ; Renin-Angiotensin System ; Sodium Chloride, Dietary ; adverse effects ; Sodium-Hydrogen Exchanger 3 ; metabolism ; Uric Acid ; metabolism

BACKGROUND AND OBJECTIVES: A relationship between renin-angiotensin system (RAS) components and metabolic syndrome (MetS) has been suggested, but not elucidated clearly. We examined the levels of RAS components in patients with and without MetS and their association with MetS in Korean population. METHODS: This study was approved by the review boards of the participating institutions and endorsed by the Korean Society of Lipid and Atherosclerosis. We screened 892 Koreans aged ≥20 years who underwent evaluation of hypertension, diabetes, or dyslipidemia at 6 tertiary hospitals in 2015–2016. After excluding patients who were taking diuretics, β-blockers, or RAS blockers, or suspected of primary aldosteronism, 829 individuals were enrolled. Anthropometric and biochemical parameters including aldosterone, plasma renin activity (PRA), and aldosterone-to-PRA ratio were evaluated. The homeostasis model assessment for insulin resistance (HOMA-IR) were used for evaluating insulin resistance. RESULTS: The mean age of the participants was 52.8±12.8 years, 56.3% were male, and their mean systolic and diastolic blood pressures were 133.9±20.0 and 81.2±14.6 mmHg, respectively. The levels of serum aldosterone, but not PRA, were significantly higher in subjects with MetS than in those without (20.6±33.6 vs. 15.3±12.2 ng/dL, p < 0.05), and positively correlated with waist circumference, blood pressure, triglycerides, and glycated hemoglobin. The levels of aldosterone were independently associated with the number of MetS components and HOMA-IR after adjusting for conventional risk factors. CONCLUSIONS: Serum aldosterone levels were higher in Korean adults with MetS than in those without. This finding suggests that increased aldosterone level might be closely associated with insulin resistance.
Adult ; Aldosterone ; Atherosclerosis ; Blood Pressure ; Diuretics ; Dyslipidemias ; Hemoglobin A, Glycosylated ; Homeostasis ; Humans ; Hyperaldosteronism ; Hypertension ; Insulin Resistance ; Insulin ; Male ; Metabolic Syndrome X ; Plasma ; Renin ; Renin-Angiotensin System ; Risk Factors ; Tertiary Care Centers ; Triglycerides ; Waist Circumference

Hypercholesterolemia and hypertension are among the most important risk factors for cardiovascular (CV) disease. They are also important contributors to metabolic diseases including diabetes that further increase CV risk. Updated guidelines emphasize targeted reduction of overall CV risks but do not explicitly incorporate potential adverse metabolic outcomes that also influence CV health. Hypercholesterolemia and hypertension have synergistic deleterious effects on interrelated insulin resistance and endothelial dysfunction. Dysregulation of the renin-angiotensin system is an important pathophysiological mechanism linking insulin resistance and endothelial dysfunction to atherogenesis. Statins are the reference standard treatment to prevent CV disease in patients with hypercholesterolemia. Statins work best for secondary CV prevention. Unfortunately, most statin therapies dose-dependently cause insulin resistance, increase new onset diabetes risk and exacerbate existing type 2 diabetes mellitus. Pravastatin is often too weak to achieve target low-density lipoprotein cholesterol levels despite having beneficial metabolic actions. Renin-angiotensin system inhibitors improve both endothelial dysfunction and insulin resistance in addition to controlling blood pressure. In this regard, combined statin-based and renin-angiotensin system (RAS) inhibitor therapies demonstrate additive/synergistic beneficial effects on endothelial dysfunction, insulin resistance, and other metabolic parameters in addition to lowering both cholesterol levels and blood pressure. This combined therapy simultaneously reduces CV events when compared to either drug type used as monotherapy. This is mediated by both separate and interrelated mechanisms. Therefore, statin-based therapy combined with RAS inhibitors is important for developing optimal management strategies in patients with hypertension, hypercholesterolemia, diabetes, metabolic syndrome, or obesity. This combined therapy can help prevent or treat CV disease while minimizing adverse metabolic consequences.
Atherosclerosis ; Blood Pressure ; Cardiovascular Diseases ; Cholesterol ; Diabetes Mellitus, Type 2 ; Humans ; Hydroxymethylglutaryl-CoA Reductase Inhibitors* ; Hypercholesterolemia ; Hypertension ; Insulin Resistance ; Lipoproteins ; Metabolic Diseases ; Obesity ; Pravastatin ; Renin-Angiotensin System ; Risk Factors

Fimasartan is a nonpeptide angiotensin II receptor blocker. In a previous study that compared the pharmacokinetics (PK) of fimasartan between patients with hepatic impairment (cirrhosis) and healthy subjects, the exposure to fimasartan was found to be higher in patients, but the decrease of blood pressure (BP) was not clinically significant in those with moderate hepatic impairment. The aims of this study were to develop a population PK-pharmacodynamic (PD) model of fimasartan and to evaluate the effect of hepatic function on BP reduction by fimasartan using previously published data. A 2-compartment linear model with mixed zero-order absorption followed by first-order absorption with a lag time adequately described fimasartan PK, and the effect of fimasartan on BP changes was well explained by the inhibitory sigmoid function in the turnover PK-PD model overlaid with a model of circadian rhythm (NONMEM version 7.2). According to our PD model, the lower BP responses in hepatic impairment were the result of the increased fimasartan EC₅₀ in patients, rather than from a saturation of effect. This is congruent with the reported pathophysiological change of increased plasma ACE and renin activity in hepatic cirrhosis.
Absorption ; Blood Pressure ; Circadian Rhythm ; Colon, Sigmoid ; Healthy Volunteers ; Humans ; Linear Models ; Liver Cirrhosis* ; Liver* ; Pharmacokinetics ; Plasma ; Receptors, Angiotensin ; Renin