Increase In Mean Blood Pressure Research Articles

Physiological stressor impact on peripheral facial temperature, Il-6 and mean arterial pressure, in young people.

Nowadays, stress is part of everyday life, whose long-term effects can trigger health risks. Among the main alterations that occur in the human body we can find the variation of inflammatory activity, blood pressure, and facial peripheral temperature. The objective of this work is to show the facial thermal behavior for men and women, as well as the differences in vascular and inflammatory responses induced by the effect of acute social stress. The Trier Social Stress Test was applied to 15 women and 15 men, free of disease, with an average age of 23.8 years and a standard deviation of 5.52. After capturing the baseline state, and at the end of the test, the inflammatory activity was measured through salivary interleukin-6; the mean blood pressure, and the capture of facial thermographic images. For the thermal images, six regions of interest (biothermomarkers) were analyzed: forehead, right cheek, left cheek, chin, nose, and corrugator muscle. The results obtained after analyzing the information were: an increase in inflammatory activity, an increase in mean blood pressure, and significant temperature changes in different areas of interest of the face, depending on gender. For men, it only appeared in the region of the nose and women's forehead, cheeks, and nose. Furthermore, the correlation between the three variables (il-6, blood pressure, and temperature) was performed and no significant values were found. Regarding the relationship between genders, only significant values were found for il-6.

Influence of repetitions on the Valsalva maneuver

ObjectiveIn autonomic units, patients perform several short Valsalva maneuvers (VMs) while learning the procedure. The effects of repeated VMs on cardiovascular elicited responses were assessed. Methods14 healthy volunteer subjects were selected (aged 22–26). VMs were performed every 3 min up to 6 times in a reclined sitting position. Changes in blood pressure (BP), heart rate (HR) and baroreflex sensitivity indexes were evaluated. Subjects were classified according to their adrenergic response patterns. ResultsVMs repetitions evoked a progressive decrease in BP during phases II and III and a reduced increase in mean BP at late phase II. Increased bradycardia at early phase II and IV was also observed. Last two VMs showed a significant increase in Valsalva ratio, while other indexes remained unaltered. Subjects with balanced adrenergic responses presented extended pressure recovery time from the third repetition and lower BP values than those with augmented or suppressed adrenergic responses. ConclusionsSignificant changes in BP and HR at certain phases were observed when consecutive VMs were performed in young subjects in a reclined position. The most affected baroreflex index was the Valsalva ratio. Adrenergic response patterns showed differences that should be considered in order to avoid false positives. SignificanceWe recommend not repeating the VM more than 4 times and revisiting the role and reliability of the Valsalva ratio.

Effect of dexmedetomidine on attenuation of hemodynamic response to intubation, skin incision, and sternotomy in coronary artery bypass graft patients: A double-blind randomized control trial.

Background and Aims:Coronary artery bypass grafting (CABG) surgery involves various noxious stimuli resulting in stress response, which in turn increases the risk of perioperative myocardial ischemia. The present study was conducted to evaluate the effect of dexmedetomidine on the attenuation of hemodynamic response to intubation, skin incision, and sternotomy in CABG surgery.Material and Methods:Sixty patients were randomized into two groups of 30 each. Group D patients received dexmedetomidine 1 μg/kg as loading dose over 10 min, followed by continuous infusion of 0.5 μg/kg/h. In group P, normal saline was infused as loading and maintenance dose at similar rate. Hemodynamic parameters, total induction dose of thiopentone, and adverse effects were recorded. Statistical analysis was performed using SPSS version 20.0. Chi-square test and ANNOVA test were used and P < 0.05 was considered significant.Results:The percentage increase in heart rate was significantly lesser in group D than group P after intubation (7.04% v/s 15.08%), skin incision (5.91% v/s 10.11%), and sternotomy (5.33% v/s 11.65%). Similarly increase in systolic, diastolic, and mean blood pressure were significantly lesser in group D than group P after intubation, skin incision, and sternotomy. There was a significant reduction of mean total of thiopentone in group D in comparison to group P. (1.16 mg/kg v/s 2.44 mg/kg) (P<0.001).Conclusion:Dexmedetomidine resulted in significant attenuation of hemodynamic response to intubation, skin incision, and sternotomy in CABG surgery without significant adverse effects. It also significantly reduced the dose of thiopentone required for induction.

Effects of obesity on sympathetic nervous system

Background: Obesity is a chronic, relapsing, neurochemical disorder controlled by the autonomic nervous system. It is an imbalance in the energy homeostasis that leads to cardiovascular conditions such as hypertension, ischemic heart disease, atherosclerosis, and stroke. The sympathetic nervous system (SNS) plays an important role in the regulation of metabolic and cardiovascular homeostasis. SNS activation is characteristic of a number of metabolic and cardiovascular diseases that occur more frequently in obese individuals. Aims and Objective: This study aims to assess the relationship between cardiac autonomic function (handgrip and cold pressor test [CPT]) and obesity in adults. Materials and Methods: This is an experimental analytical non-randomized study. Body mass index was calculated by Quetelet’s index. Cardiac autonomic function tests employed were handgrip test (HGT) and CPT. Results: In HGT, the mean increase in systolic blood pressure (SBP) and diastolic BP (DBP) was 9.85 mmHg and 8.54 mmHg in obese and 15.88 mmHg and 14.15 mmHg in non-obese. While in CPT, the mean increase in SBP and DBP was 11.2 mmHg and 9.12 mmHg in obese and 17.00 mmHg and 14.62 mmHg in non-obese. Conclusion: The increase in SBP and DBP was significantly less in obese as compared to non-obese during autonomic function tests.

Phytochemical, antihypertensive and nephroprotective study of aqueous extract of the stems and roots of Selaginella vogelii Mett (Selaginellaceae) in rats

Selaginella vogelii belongs to the Selaginellaceae family widely used in traditional medicine to treat hepatitis, cancer, cardiovascular, renal and inflammatory diseases.The present study was undertaken to evaluate the antihypertensive and nephroprotective effects of Selaginella vogelii aqueous extract.Reverse phase high-performance liquid chromatography (RP-HPLC) was used to analyze the chromatographic fingerprint and to identify various chemical components of the plant extract. The antihypertensive activity of the aqueous extract of Selaginella vogelii (100, 200 and 400mg/kg of body weight) was evaluated on an L-NAME-induced hypertension model in rat. After body weight measurement, CODA non-invasive blood pressure system was used to record cardiovascular parameters as blood pressure and heart rate. Biochemical and histological analysis were performed to demonstrate the protective effect of the aqueous extract of Selaginella vogelii in gentamicin (i.p)-induced nephrotoxicity model.The phytochemical analysis indicated the presence of phenolic acids, flavonoids, and saponins. The aqueous extract of Selaginella vogelii significantly prevented (P<.01) the increase of mean blood pressure with a maximum of 47.64% at the dose of 400mg/kg during the 4weeks of treatment. The Selaginella vogelii aqueous extract significantly reduced ALAT (60.88%), ASAT (38.84%) and creatinine (52.81%) concentrations. In the nephroprotective assay, the plant extract (400mg/kg) significantly decreased (P˂0.01) kidney weight (39.66%). Urea and creatinine rates were reduced in both tissue and serum. Histological analysis showed that, S. vogelii extract (400mg/kg) restored renal disorders induced by administration of gentamicin.The aqueous extract of Selaginella vogelii possesses antihypertensive and nephroprotective effects with an effective dose of 400mg/kg. This study indicates that the aqueous extract prevented the increase of the mean blood pressure and the nephroprotective effect may be adduced to the decrease in the creatinine and urea levels in the kidneys. The findings justify the traditional use of Selaginella vogelii.

Cardiovascular and Orthostatic Responses to a Festive Meal Associated With Alcohol in Young Men.

Aim: Sharing a festive meal associated with alcohol is quite common. While the cardiovascular changes occurring after meal ingestion of different nutrient composition has been well-established, the effects of ingesting a festive versus a standard meal accompanied with alcohol are less clear. Here, we compared the postprandial hemodynamics, cutaneous and psychomotor performance responses after ingestion of a classical Swiss festive meal [cheese fondue (CF)] versus a light ready-meal [Nasi Goreng (NG)], both accompanied with white wine.Methods: In a randomized cross over design, we examined in 12 healthy young men, the continuous cardiovascular, cutaneous, and reaction time responses to ingestion of cheese fondue versus a standard meal at rest (sitting position) and hemodynamic changes in response to orthostatic challenge (active standing) in pre- and postprandial phases.Results: Breath alcohol concentration after wine ingestion was similar after both meal types. Compared to the standard meal, consumption of CF induced higher increases in heart rate (HR), cardiac output (CO), double product (DP) and cardiac power output (CPO), greater vasodilation, and rises in skin blood flow and skin temperature. Greater increases in HR, DP, and mean blood pressure (MBP) were observed during orthostatic challenges with CF compared to NG. A two-choice reaction time task revealed similar reaction times with both meals, suggesting no influence of meal composition on psychomotor performance.Conclusion: In sitting position, CF ingestion induced a more important cardiovascular load compared to NG. Although the dose of alcohol and the festive meal used here did not lead to orthostatic hypotension, eating CF induced a greater cardiometabolic load suggesting that hemodynamic reserves have been encroached during active standing. This may impede the cardiovascular capacity during physical exercise or stress situations, particularly in elderly subjects who are at greater risk for postprandial hypotension and cardiovascular diseases.

Brain perivascular macrophages contribute to the development of hypertension in stroke-prone spontaneously hypertensive rats via sympathetic activation.

Hypertension is associated with systemic inflammation. The activation of the sympathetic nervous system is critically involved in the pathogenesis of hypertension. Brain perivascular macrophages (PVMs) can be affected by circulating inflammatory cytokines, and the contribution of brain PVMs to sympathoexcitation has been demonstrated in a heart failure model. We thus investigated whether brain PVMs contribute to the development of hypertension through sympathoexcitation. Stroke-prone spontaneously hypertensive rats (SHRSP) developed hypertension over an 8-week period from 4 to 12 weeks of age. The number of brain PVMs and plasma interleukin-1β levels significantly increased at the ages of 8 and 12 weeks in SHRSP compared with normotensive Wistar-Kyoto rats (WKY). To determine the contribution of brain PVMs to blood pressure elevation, we intracerebroventricularly injected liposome-encapsulated clodronate, which eliminates macrophages by inducing apoptosis, into 8-week-old rats; we then assessed its effects in 10-week-old rats. Clodronate treatment attenuated the increase in mean blood pressure in SHRSP but not in WKY. Clodronate treatment reduced the depressor effect of hexamethonium, an index of sympathetic activity; it also reduced neuronal activity in sympathetic regulatory nuclei such as the hypothalamic paraventricular nucleus and rostral ventrolateral medulla and reduced the expression of cyclooxygenase-2 and prostaglandin E2, a downstream pathway in activated macrophages, in SHRSP but not in WKY. Furthermore, clodronate treatment attenuated the increase in blood pressure and renal sympathetic nerve activity in response to an acute intravenous injection of interleukin-1β in WKY. In conclusion, brain PVMs contribute to the development of hypertension via sympathetic activation. PVMs may be activated by increased levels of circulating interleukin-1β.

Changes in pulse pressure × heart rate, hs-CRP, and arterial stiffness progression in the Chinese general population: a cohort study involving 3978 employees of the Kailuan Company.

BackgroundPulse wave velocity (PWV) is a marker of arterial stiffness, which represents sub-clinical atherosclerosis. Pulsatile stress and high-sensitivity C-reactive protein (hs-CRP) are associated with arteriosclerosis. However, there is no prospective data confirming whether changes in pulsatile stress and inflammatory markers affect the progression of arterial stiffness. The aim of this study was to investigate the relationships over time between the effects of changes in pulsatile stress and hs-CRP, and arterial stiffness progression during a 2-year follow-up.MethodsWe performed a longitudinal study involving 3978 participants. All participants underwent a physical examination in 2010–2011 and 2012–2013, during which we measured participants' hs-CRP levels, brachial–ankle pulse wave velocity (baPWV), and pulsatile stress.ResultsBaseline hs-CRP was correlated with baPWV (r = 0.18, P = 0.000); however the correlation was weaker than that with systolic blood pressure (r = 0.65), pulsatile stress (r = 0.57), and rate-pressure product (r = 0.58). Multiple linear regression analysis demonstrated that changes in pulsatile stress, mean arterial pressure, and low-density lipoprotein-C (LDL-C) were positively correlated with changes in baPWV, with correlation coefficients of 0.27, 0.25, and 0.07, respectively, but not with changes in hs-CRP. Moreover, each 100-aU increase in pulsatile stress, 1 mmHg increase in mean blood pressure, and 1 mmol/L increase in LDL-C was associated with a 3 cm/s, 4.78 cm/s, and 17.37 cm/s increase in baPWV, respectively.ConclusionsPulsatile stress increases are associated with arterial stiffness progression, but that changes in hs-CRP had no effect on arterial stiffness progression. Hs-CRP may simply be a marker of inflammation in arterial stiffness and has no association with arterial stiffness progression.

Aliskiren, Fosinopril, and Their Outcome on Renin-Angiotensin-Aldosterone System (RAAS) in Rats with Thyroid Dysfunction.

Background and Objectives Thyroid hormones have an important role in the growth and development of various tissues including the kidney, which is the major site of renin release and the consequent angiotensin and aldosterone formation. Therefore any derangement in thyroid function can result in abnormal functioning in the renin-angiotensin-aldosterone system. The current study was undertaken to find the impact of using a direct renin inhibitor (Aliskiren) and an angiotensin-converting enzyme inhibitor (Fosinopril) on the components of the renin-angiotensin-aldosterone system (RAAS) in rats with thyroid dysfunctions. Method Forty-two male albino rats were divided into three subgroups. First group (6 rats) served as control. Second group (18 rats) served as hyperthyroid group (6 rats positive control, 6 rats given Aliskiren, and 6 rats given Fosinopril). Third group (18 rats) served as hypothyroid group (6 rats positive control, 6 rats given Aliskiren, and 6 rats given Fosinopril). Induction of hyperthyroidism and hypothyroidism was done through daily oral administration of L-Thyroxine and Propylthiouracil, respectively. On day 40 of the study, the rats were sacrificed and blood was collected for estimation of renin, angiotensin I, angiotensin II, aldosterone, TSH, T3, and T4. The collected blood samples were also used for estimation of levels blood urea, serum creatinine, liver enzymes, and serum electrolytes. Blood pressure and urine collection were done on days 1 and 40. The collected urine was used for estimation of urine flow, sodium excretion, and potassium excretion rates. Results In hypothyroid induced rats, serum renin level dropped as expected, while the use of Aliskiren and Fosinopril on these hypothyroid rats raised renin level due to the feedback mechanism. Both angiotensin I and II were significantly (P <0.05) lower than normal levels in the hypothyroid rats, unlike the level of aldosterone, which was higher than normal level. There was nonsignificant lowering in BP (systolic, diastolic, and mean BP) in the hypothyroid rats. Treatment of these rats with Aliskiren and Fosinopril did not lower the blood pressure more than normal when compared to the hypothyroid group. The hypothyroid rats also showed a decrease in level of serum creatinine. In hyperthyroid rats, there was a rise in levels of serum renin, angiotensin II, and aldosterone; nevertheless, the increase in angiotensin I level was significant. The use of Aliskiren and Fosinopril increased the level of renin nonsignificantly (decreased angiotensin I significantly). Hyperthyroid rats showed a significant increase in systolic, diastolic, and mean blood pressure. Both Aliskiren and Fosinopril increased urine flow, Na+ excretion, and K+ excretion rates. Aliskiren was better at reducing the high blood pressure. Conclusion Aliskiren and Fosinopril in hyperthyroid rats decreased serum angiotensin I, angiotensin II, and aldosterone. Blockade of renin and inhibition of angiotensin-converting enzyme both resulted in a rebound increase in level of renin in hypothyroid rats. Aliskiren is better at controlling blood pressure in hyperthyroid rats. Urine flow, sodium excretion, and potassium excretion rates were improved by the use of Aliskiren and Fosinopril in hyperthyroid rats.

GABAA receptors modulate sympathetic vasomotor outflow and the pressor response to skeletal muscle metaboreflex activation in humans.

The activation of the group III/IV skeletal muscle afferents is one of the principal mediators of cardiovascular responses to exercise; however, the neuronal circuitry mechanisms that are involved during the activation of group III/IV muscle afferents in humans remain unknown. Recently, we showed that GABAergic mechanisms are involved in the cardiac vagal withdrawal during the activation of mechanically sensitive (predominantly mediated by group III fibres) skeletal muscle afferents in humans. In the present study, we found that increases in muscle sympathetic nerve activity and mean blood pressure during isometric handgrip exercise and postexercise ischaemia were significantly greater after the oral administration of diazepam, a benzodiazepine that increases GABAA activity, but not after placebo administration in young healthy subjects. These findings indicate for the first time that GABAA receptors modulate sympathetic vasomotor outflow and the pressor responses to activation of metabolically sensitive (predominantly mediated by group IV fibres) skeletal muscle afferents in humans. Animal studies have indicated that GABAA receptors are involved in the neuronal circuitry of the group III/IV skeletal muscle afferent activation-induced neurocardiovascular responses to exercise. In the present study, we aimed to determine whether GABAA receptors modulate the neurocardiovascular responses to activation of metabolically sensitive (predominantly mediated by group IV fibres) skeletal muscle afferents in humans. In a randomized, double-blinded, placebo-controlled and cross-over design, 17 healthy subjects (eight women) performed 2min of ischaemic isometric handgrip exercise at 30% of the maximal voluntary contraction followed by 2min of postexercise ischaemia (PEI). Muscle sympathetic nerve activity (MSNA), blood pressure (BP) and heart rate (HR) were continuously measured and trials were conducted before and 60min after the oral administration of either placebo or diazepam (10mg), a benzodiazepine that enhances GABAA activity. At rest, MSNA was reduced, whereas HR and BP did not change after diazepam administration. During ischaemic isometric handgrip, greater MSNA (pre: ∆13±9burstsmin-1 vs. post: ∆29±15burstsmin-1 , P<0.001), HR (pre: ∆23±11beatsmin-1 vs. post: ∆31±17beatsmin-1 , P<0.01) and mean BP (pre: ∆33±12mmHg vs. post: ∆37±12mmHg, P<0.01) responses were observed after diazepam. During PEI, MSNA and mean BP remained elevated from baseline before diazepam (∆10±8burstsmin-1 and ∆25±14mmHg, respectively) and these elevations were increased after diazepam (∆17±12burstsmin-1 and ∆28±13mmHg, respectively) (P≤0.05). Importantly, placebo pill had no effect on neural, cardiac and pressor responses. These findings demonstrate for the first time that GABAA receptors modulate MSNA and the pressor responses to skeletal muscle metaboreflex activation in humans.

Large vessels as a tree of transmission lines incorporated in the CircAdapt whole-heart model: A computational tool to examine heart-vessel interaction.

We developed a whole-circulation computational model by integrating a transmission line (TL) model describing vascular wave transmission into the established CircAdapt platform of whole-heart mechanics. In the present paper, we verify the numerical framework of our TL model by benchmark comparison to a previously validated pulse wave propagation (PWP) model. Additionally, we showcase the integrated CircAdapt–TL model, which now includes the heart as well as extensive arterial and venous trees with terminal impedances. We present CircAdapt–TL haemodynamics simulations of: 1) a systemic normotensive situation and 2) a systemic hypertensive situation. In the TL–PWP benchmark comparison we found good agreement regarding pressure and flow waveforms (relative errors ≤ 2.9% for pressure, and ≤ 5.6% for flow). CircAdapt–TL simulations reproduced the typically observed haemodynamic changes with hypertension, expressed by increases in mean and pulsatile blood pressures, and increased arterial pulse wave velocity. We observed a change in the timing of pressure augmentation (defined as a late-systolic boost in aortic pressure) from occurring after time of peak systolic pressure in the normotensive situation, to occurring prior to time of peak pressure in the hypertensive situation. The pressure augmentation could not be observed when the systemic circulation was lumped into a (non-linear) three-element windkessel model, instead of using our TL model. Wave intensity analysis at the carotid artery indicated earlier arrival of reflected waves with hypertension as compared to normotension, in good qualitative agreement with findings in patients. In conclusion, we successfully embedded a TL model as a vascular module into the CircAdapt platform. The integrated CircAdapt–TL model allows detailed studies on mechanistic studies on heart-vessel interaction.

Hemodynamics of infants with strong fluctuations of internal cerebral vein.

There is a high incidence of intraventricular hemorrhage in extremely low-birthweight (ELBW) infants of low gestational age with high-grade fluctuations in the perfusion waveform of the internal cerebral vein. This study investigated changes in the hemodynamic status of ELBW infants during initial strong fluctuations in the perfusion waveform of the internal cerebral vein. We evaluated the perfusion waveform of the internal cerebral vein in 192 ELBW infants from birth, every 8h for a total of 120h. Sixty-seven infants had high-grade fluctuations. On the basis of the presence of patent ductus arteriosus (PDA), patients were subdivided into PDA(-) (n=32) and PDA(+) (n=35) groups. During the first high-grade fluctuation, the PDA(-) group had significant increases in systolic, diastolic, and mean blood pressure (P<0.001 for all). The PDA(+) group did not have significant changes in blood pressure but did have significant increases in the number of interruptions or regurgitations of diastolic renal arterial blood flow (P=0.04) and end-diastolic left pulmonary arterial flow velocity (P<0.001), indicating increased left-to-right shunt. Blood pressure elevation may underlie fluctuations in the perfusion waveform of the internal cerebral vein and lead to the first high-grade increases during acute management of ELBW infants. When no elevation in blood pressure occurred, hemodynamically significant PDA was considered a potential underlying factor.

Study of blood pressure in relation with age, sex and BMI in school going children of age group 5-15 years in Amalapuram, Andhra Pradesh, India

Background: The measurement of blood pressure is an important component of routine Pediatric physical examination. Children with higher levels of blood pressure tend to maintain higher blood pressure levels in adulthood in comparison to their peer group. The aims and objectives of this study were to define the normal pattern of blood pressure and prevalence of hypertension in urban school children between the age group of 5-15 years and to evaluate relationship of blood pressure with variables such as age, sex, height, weight and BMI in Amalapuram, Andhra Pradesh.Methods: This was a prospective cross-sectional observational study conducted from July 2016 to December 2018 in Department of Pediatrics, KIMS Amalapuram.Results: The overall prevalence of hypertension in the present study was 3.2%. Of these 16 children 11 were males amounting to 4.41% of total number of males and 5 were females amounting to 1.99% of total number of females. The prevalence of hypertension was more in the males. It was observed that there is not much increase in mean blood pressure up to 130 cms (both in males and females) and increased significantly and gradually in children above 130 cms of height. Blood pressure increases gradually and in a proportionate manner with increase in weight and BMI.Conclusions: Blood pressure is an important vital sign which reflects the integrity of the cardiovascular system, renal, endocrinal system and other systems in the body. Blood pressure of an individual varies with age, sex, height, weight and BMI. It also has a strong correlation with family history of hypertension. Thus, concluded that hypertension has its roots in childhood and early adolescence.

Enhanced Carotid Body Chemosensory Discharge is Essential for the Hypertension Induced by Chronic Intermittent Hypoxia

Chronic intermittent hypoxia (CIH), the main feature of obstructive sleep apnea, enhances carotid body (CB) discharges, leading to sympathetic overflow and hypertension. CIH produces oxidative stress (ROS) in the CB, which contributes to enhance the CB drive to the brainstem and hypothalamic nuclei related to the cardiorespiratory control, such as the nucleus of the tractus solitary (NTS), the rostral ventrolateral medulla (RVLM) and the paraventricular nucleus (PVN). We hypothesized whether the enhanced CB chemosensory drive may increase ROS levels in central cardiovascular nuclei during CIH‐induced hypertension. Accordingly, we studied the effects of CB ablation on ROS formation in the NTS, PVN and RVLM of hypertensive CIH‐rats. Male Sprague‐Dawley rats (200 g) were exposed to CIH (5–6% inspired O2 for 20s, followed by room air for 280s, 12 times/h, 8 h/day), for 28 days. Arterial blood pressure (BP) was measured by radio‐telemetry (DSI, USA). Following 21 days of CIH exposure, rats were anesthetized with isofluorane in 2% O2, and the CBs were cryogenically destroyed bilaterally using a fine‐tipped forcep cooled in liquid N2. Then, rats were maintained in CIH conditions for one more week. Another group of rats were maintained in CIH or Sham conditions for 28 days. At the end of the experiments, all animals were euthanized (pentobarbital 120mg/kg i.p.) and brains were removed and frozen at −20°C. Coronal sections of the NTS, RVLM and PVN were cut and incubated for 30 min in the dark with the ROS sensitive fluorescent probe dihydroethidium (DHE 10μM, Invitrogen USA). DHE fluorescence was measured using epifluorescence microscopy (Olympus Optical, Japan) at an excitation wavelength of 543 nm. Data were analyzed by one‐way ANOVA followed by Bonferroni's test. Compared to Sham rats, CIH‐rats showed a significant increase in mean BP (□ 10 mmHg, p&lt;0.05). The CIH‐induced hypertension was abolished by the ablation of the CBs (CBA). ROS formation was markedly reduced by CBA in the NTS, RVLM and PVN of CIH‐exposed rats (CIH vs. CIH‐CBA: NTS: 6.2±1.5 vs. 1.5±02 au, RVLM: 4.9± 1.5 vs. 2.1±1.6 au, PVN: 5.4±1.8 vs. 1.6±05 au, p &lt;0.05, n= 5–6 rats). Results support the evidence for an essential role of the CBs in the development and maintenance of the CIH‐induced hypertension and oxidative stress present in the NTS, RVLM and PVNSupport or Funding InformationFONDECYT 1150040This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Amelioration of Nω‐Nitro‐L‐Arginine Methyl Ester (L‐NAME)‐induced hypertension and cardio‐renal oxidative stress by the methanol bark extract of Persea americana

Hypertension is a leading cause of cardiovascular morbidity and mortality. Uncontrolled hypertension causes end organ damage resulting in hypertensive cardiomyopathy and nephropathy. Traditionally, P. americana bark extract (PABE) is commonly used as a remedy for hypertension in Nigeria. In this study, we investigated the probable ameliorative effects of PABE on L‐NAME induced hypertension and cardiorenal oxidative stress.Sixty (60) male Wistar albino rats were grouped into six groups each containing 10 rats. Group A, the control, was administered potable water. Groups B‐F received orally, 40 mg/kg of L‐NAME only, 40 mg/kg of L‐NAME+100 mg/kg of PABE extract, 40 mg/kg of L‐NAME+200 mg/kg of PABE extract, 40 mg/kg of L‐NAME+400 mg/kg of PABE extract and 40 mg/kg of L‐NAME+ 0.25 mg/kg of lisinopril, respectively for 21 daysL‐NAME administration caused a significant (p &lt;0.05) increase in systolic, diastolic and mean arterial blood pressure as well as markers of oxidative stress namely H2O2, Malondialdehyde, Protein carbonyl and AOPP in cardiac and renal tissues. Immunohistochemistry showed increased expressions of CTn1, NRF2 and NFkB in the cardiac tissues and also KIM‐1, NRF2 and NFkB in the kidney tissues of the group treated with L‐NAME alone compared to the control.Treatment with PABE caused a significant (P&lt;0.05) decrease in blood pressure, an improvement in antioxidant defense systems, reduction in markers of oxidative stress, cardiac and renal injury and inflammation comparable with that of lisinopril.The results obtained from this study suggest the ameliorative effect of PABE on L‐NAME‐induced hypertension and cardiorenal oxidative stress and hence, its potential as an antihypertensive supplement.Support or Funding InformationTertiary Education Trust Fund (TETFUND), NigeriaThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Modulation of Nω‐nitro‐L‐arginine methyl ester (L‐NAME)‐Induced Hypertension and Cardio‐renal Oxidative Stress by Methanol Extract of Persea americana Root

Hypertension is the leading cause of cardiovascular morbidity and mortality. Uncontrolled hypertension causes end organ damage resulting in hypertensive cardiomyopathy and nephropathy. P. americana root extract (PARE) is commonly used the management of hypertension in Nigeria traditional medicine.In this study, we investigated modulatory effects of PARE on L‐NAME induced hypertension, oxidative stress and cardio‐renal complicationsSixty male rats (wistar strain) were used in this study, and they were randomly divided into six experimental groups with ten rats in each group. Group A served as the controls and they received distilled water only for the period of 21 days. Group B was given L‐NAME only at 40mg/kg while groups C, D and E were given a daily dose of L‐NAME at 40 mg/kg and methanol root extract at respective dose of 100mg/kg, 200mg/kg and 400mg/kg for 21 days. Group F was given a daily dose of L‐name+ Lisinopril (0.25mg/kg) orally for 21 days. L‐name was given at 40mg/kg daily. Blood pressure measurements were recorded in conscious animals by tail cuff plethysmography . Biochemical assays were carried out on the serum, cardiac and renal tissues to assess the enzymatic and non‐enzymatic antioxidant defense system. Immunohistochemistry was also done on cardiac and renal tissues.Treatment with L‐NAME caused a significant (p &lt;0.05) increase in systolic, diastolic and mean arterial blood pressure and markers of oxidative stress in cardiac and renal tissues. Immunohistochemistry showed increased expressions of CTn1, NRF2 and NFkB in the heart tissues and KIM‐1, NRF2 and NFkB in the kidney tissues of the group treated with L‐NAME alone compared to the control. Treatment with PARE caused a significant (P&lt;0.05) decrease in blood pressure, an improvement in antioxidant defense systems, reduction in markers of oxidative stress, cardiac and renal injury and inflammation comparable with that of lisinopril..The results obtained from this study suggest that PARE can modulate high blood pressure with associated end organ damage and cardio‐renal oxidative stress in L‐NAME induced hypertensionThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Mechanisms of Salt‐Sensitive Hypertension in a Mouse Model of ACTH‐Dependent Cushing Syndrome

Salt‐sensitive blood pressure (BP) reflects underlying renal and vascular (endothelial) dysfunction. People with abnormal glucocorticoid homeostasis, such as in Cushing syndrome and obesity, are often salt‐sensitive but the underlying mechanisms are not clearly defined1,2. Here, we used a mouse model to examine the effect of ACTH excess on blood pressure and salt‐sensitivity. To test this, radio telemetry was used to track BP longitudinally and measure the effect of high salt diet before and after chronic ACTH treatment in C57BL/6J mice (n=6). Data are mean ± SD. After 7 days of baseline measurements, mean BP was 105.8 ± 6.5mmHg before being placed on a high salt diet (3 % Na+ by weight) for a further 7 days. BP increased ~12 mmHg over the first 3 days before declining to 113.1 ± 7.2mmHg. BP returned to 107.7 ± 10.4mmHg, similar to baseline, after a 5‐day washout period. Mice were then treated with ACTH (2.5μg/day). ACTH increased mean BP to 115.5 ± 5.0mmHg with a flattening of the diurnal rhythm following 13 days infusion. When placing these mice on a high salt diet, mean BP increased and stabilised to 136.1 ± 13.4mmHg after 14 days. These data show that chronic ACTH excess contributes to salt‐sensitivity. To investigate potential mechanisms of salt‐sensitivity, the acute pressure natriuresis (PN) response of renal artery function were examined in separate cohorts of mice treated with either vehicle or ACTH (2.5μg/day; n=6 per group) for 14 days. PN response was induced in anaesthesised mice (120mg/kg Inactin) by sequential arterial ligation. BP increased ~40mmHg following ligations in both vehicle and ACTH groups. In vehicle‐treated mice, fractional sodium excretion increased from 0.2 ± 0.2 to 5.0 ± 4.2μmol/min. The natriuretic response was significantly blunted in ACTH‐treated mice, reaching 2.1 ± 1.1μmol/min at its peak. We next investigated vascular function in ACTH‐excess ex vivo by wire myography in isolated mesenteric and renal arteries. Vascular reactivity to phenylephrine (PHE), acetylcholine (ACh) and sodium nitroprusside (SNP) was assessed. ACTH‐excess caused vascular dysfunction in the renal artery but not in the mesenteric artery. ACTH‐excess resulted in a reduction in sensitivity to vasoconstrictor PHE (p=0.0005) and endothelium dependent (ACh) and endothelium independent (SNP) vasodilators (p=0.0128 and p=0.0002, respectively). These data show that chronic glucocorticoid excess contributes to salt‐sensitivity with potential mechanisms behind this being impairment of the acute natriuretic and diuretic response to increased BP and renal vascular dysfunction.Support or Funding InformationSupported by British Heart Foundation PhD studentships FS/16/54/32730 &amp; FS/15/63/32033.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Assessment of the Relationship Between Ambient Temperature and Home Blood Pressure in Patients From a Web-Based Synchronous Telehealth Care Program: Retrospective Study.

BackgroundDecreased ambient temperature significantly increases office blood pressure, but few studies have evaluated the effect of ambient temperature on home blood pressure.ObjectiveWe aimed to investigate the relationship between short-term ambient temperature exposure and home blood pressure.MethodsWe recruited patients with chronic cardiovascular diseases from a telehealth care program at a university-affiliated hospital. Blood pressure was measured at home by patients or their caregivers. We obtained hourly meteorological data for Taipei (temperature, relative humidity, and wind speed) for the same time period from the Central Weather Bureau, Taiwan.ResultsFrom 2009 to 2013, we enrolled a total of 253 patients. Mean patient age was 70.28 (SD 13.79) years, and 66.0% (167/253) of patients were male. We collected a total of 110,715 home blood pressure measurements. Ambient temperature had a negative linear effect on all 3 home blood pressure parameters after adjusting for demographic and clinical factors and antihypertensive agents. A 1°C decrease was associated with a 0.5492-mm Hg increase in mean blood pressure, a 0.6841-mm Hg increase in systolic blood pressure, and a 0.2709-mm Hg increase in diastolic blood pressure. This temperature effect on home blood pressure was less prominent in patients with diabetes or hypertension. Antihypertensive agents modified this negative effect of temperature on home blood pressure to some extent, and angiotensin receptor blockers had the most favorable results.ConclusionsShort-term exposure to low ambient temperature significantly increased home blood pressure in patients with chronic cardiovascular diseases. Antihypertensive agents may modify this effect.

Reduction in Hemodynamic Changes during Direct Laryngoscopy and Intubation by Intravenous Clonidine or Nalbuphine Premedication - A Comparative Evaluation

Background: Accentuated hemodynamic changes during direct laryngoscopy can be modified by appropriate premedication. The present study was aimed to comparatively evaluate the clinical efficacy of intravenous clonidine with nalbuphine premedication for reduction in hemodynamic changes during direct laryngoscopy and intubation. &nbsp;Subjects and Methods: Sixty adult consenting patients of ASA physical status I and II of either gender, were randomized into two equal groups of 30 patients each to receive either clonidine (2 µg/kg) Group I or nalbuphine (0.2 mg/kg) Group II, intravenously 10 minutes before induction. Anesthetic technique was standardised and direct laryngoscopy with intubation was facilitated with vecuronium bromide. Changes in heart rate, arterial blood pressure and ECG were recorded at baseline, after giving study drug, after laryngoscopy and intubation, then after at 1st, 2nd, 3rd, 5th, 10th, and 15th min of intubation and were noted as primary end points. Any side effects and complications were recorded as secondary end points. Results: After premedication in patients of comparable demographic profile, the fall in heart rate and blood pressure showed statistically significant difference between the groups. After laryngoscopy and intubation, the increase in mean heart rate and mean blood pressure occurred immediately in patients of both groups but persisted up to 5 to 7 min in patients of clonidine group and up to 10 minutes in patients of nalbuphine group with statistically significant difference between the groups. Conclusion: Intravenous clonidine premedication (2 µg/kg) could effectively reduce the hemodynamic changes during direct laryngoscopy and intubation when compared to intravenous nalbuphine (0.2 mg/kg), administered 10 min before induction.

The phospholipid fraction obtained from egg yolk reduces blood pressure increase induced by acute stress in spontaneously hypertensive rats.

Despite continuous research, an improved understanding of the pathophysiology of hypertension and the development of new antihypertensive therapies, hypertension is still the most prevalent chronic cardiovascular disease (CVD) among adults in Western societies. Stress is a common factor related to cardiovascular morbidity. An increase in blood pressure is one of the most common reactions to stress. Chronic and acute stress have also been related to cardiovascular disorders. Polyunsaturated fatty acids (PUFAs) have attracted considerable interest as potential complementary therapy for the treatment of CVD, including hypertension. Egg yolk, rich in PUFAs and phospholipids, might be a good source of phospholipids and PUFAs. The current study was aimed at investigating the potential effect of the phospholipid fraction of eggs on blood pressure changes in spontaneously hypertensive rats (SHRs) as a response to acute stress. Male, 7-week-old SHRs received dietary phospholipid fraction for 12 weeks. The control animals received standard feed. At the end of the treatment, they were exposed to 40 min of white noise in order to induce acute stress. Then, blood pressure measurements were carried out under normal conditions for 12 h before and during the acute stress procedure. Blood pressure was measured by telemetry. Diastolic, systolic and mean blood pressure were significantly lower in the SHRs treated with phospholipid fraction than in the control group. The acute stressor caused a significant increase in diastolic, systolic and mean blood pressure in both the treated and untreated animals, but the increase in blood pressure as a response to the stressor was significantly less pronounced in the rats treated with phospholipid fraction than in control rats. These results show that egg phospholipids can limit a stress-induced rise in blood pressure. The results of this research show that phospholipid fraction derived from egg yolk reduces stress-induced increases in blood pressure.