bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract P116: Postpartum Catastrophe With Intracerebral Hemorrhage and Concurrent Cardiomyopathy
Authors: Sabzwari Syed Rafay Ali , Lin Yan , Dai Shengchuan
Published: July 2021

Introduction:
Postpartum Cerebral Angiopathy (PCA) or Reversible Cerebral Vasoconstriction Syndrome (RCVS) is a rare but important postpartum syndrome characterized by severe headaches with complications including seizures and intracranial hemorrhages. Peripartum cardiomyopathy (PPCM) is a known non-ischemic cardiomyopathy occurring mostly in the immediate postpartum period. This case is one of its kind to show the unique combination of PPCM and PCA.

Case Report:
32 years old Hispanic female with no past medical history presented with worsening headache since epidural anesthesia used for her uneventful spontaneous vaginal delivery six days ago. While in ED she suddenly developed left hemiplegia and an immediate CT head showed right basal ganglia intracerebral hemorrhage causing 10mm right to left midline shift. An emergent frontotemporal craniotomy and evacuation of hemorrhage was done. A cerebral angiogram the next day showed diffuse cerebral arterial vasoconstriction responding to intra-arterial verapamil suggestive of RCVS. An echocardiogram was completely normal and vasculitis workup was negative. Patient was started on nimodipine however she became hypotensive requiring pressors. A week later repeat angiography showed persistent vasospasm and a repeat echocardiogram showed dilated left and right ventricles with global impairment in systolic function and an EF of 15-20%. The subsequent day there was a change in her neurological status where she lost all brain and brainstem reflexes, pupils got fixed and dilated. CT brain showed global edema and tonsillar herniation. Apnea test was done which was consistent with the diagnosis of brain death.

Discussion:
The pathophysiologic mechanism of RCVS is believed to be related to altered cerebral auto regulation in response to endothelial injury that usually resolves in 3 months. The diagnosis can be made by cerebral angiography, MRA or CTA that shows multifocal segmental arterial constrictive lesions. It is likely that a combination of diffuse persistent cerebral vasospasm accompanied by poor cardiac function that culminated in eventual brain death of this healthy, postpartum patient. Management includes calcium channel blockers, sequential cerebral angiograms and supportive care.
Abstract P122: Plasma Circulating microRNAs as Potential Biomarkers in Chronic Kidney Disease
Authors: Berillo Olga , Huo Ku-Geng , Fraulob-Aquino Júlio C , Richer Chantal , Rehman Asia , Briet Marie , Boutouyrie Pierre , Lipman Mark L , Sinnett Daniel , Paradis Pierre , Schiffrin Ernesto L
Published: July 2021

Background:
Chronic kidney disease (CKD) is a global health burden with a worldwide prevalence of 13.4% for stage 5 and 10.6% for stage 3-5. There is an epidemiological association between hypertension (HTN) and CKD. The prevalence of high blood pressure (BP) has been reported to be over 85% in stage 3 and over 90% in stage 4-5 CKD patients. Circulating cell-free small non-coding RNAs called microRNA (miRNA) have been shown to associate with different pathologies including cancer and cardiovascular disease, and accordingly possesses potential to serve as biomarkers with clinical application. We aimed to identify differentially expressed (DE) miRNAs that may be related to CKD.

Methods and Results:
Normotensive, HTN (systolic BP > 135 mmHg or diastolic BP of 85-115 mmHg with BPtru) and CKD (estimated glomerular filtration rate (eGFR) < 60mL/min/m
2
) subjects (n=15-16 per group) were studied. Platelet-free plasma was isolated by a 2-step centrifugation (1000xg followed by 10,000xg) from 6 ml total blood. Plasma miRNAs were extracted using the QIAamp Circulating Nucleic Acid Kit. The quantity and quality of RNA were assessed using an Agilent 2100 Bioanalyzer. cDNA libraries were prepared using the TruSeq Small RNA Library Prep Kit, and sequenced with the HiSeq 2500 platform. FastQC was used for quality control. Sequences were mapped by STAR to the hg38 genome and annotated by miRDeep2. DE miRNAs were identified using EdgeR, which found 6 up-regulated and 3 down-regulated miRNAs uniquely associated with the HTN group, 2 up-regulated and 12 down-regulated miRNAs uniquely associated with the CKD group and 3 down-regulated miRNAs in both groups (
P
<0.01 & q<0.1). Two down-regulated miRNAs in the HTN group, miR-26a-5p (r=-0.33,
P
<0.05) and miR-151a-5p (r=-0.33,
P
<0.05), were correlated with SBP. One up-regulated miRNA in CKD group, let-7g-5p (r=0.31,
P
<0.05), was correlated with eGFR.

Conclusions and Perspectives:
DE platelet-free plasma miRNAs were identified in HTN and CKD patients. Some miRNAs may have the potential to serve as biomarkers in CKD.
Abstract P130: A Map of SPRINT’s Data-free Zone
Authors: Laffin Luke J , Besser Stephanie A , Alenghat Francis J
Published: July 2021

120 mmHg is an optimal SBP goal according to the SPRINT trial. However, certain inclusion and exclusion criteria cloud its broad applicability. It is critical to understand which patients are well represented and reasonable candidates for intensive BP goals. Using only trial inclusion and exclusion criteria diminishes the fact that subjects are unevenly distributed across these criteria. A patient may fit study constraints, yet be poorly represented. Conversely, a patient may be excluded based on a parameter, and declared an inhabitant of a "data-free zone," yet in other respects resemble the trial population.

We defined and mapped the "data-rich, data-limited, and data -free zones" of SPRINT based on subjects’ baseline characteristics and not on inclusion and exclusion criteria. For each participant (n=9245), a z-score was computed for 6 variables: age, SBP, glucose, non-HDL-C, creatinine, and BMI. Standardized coefficients from multivariable logistic regression, based on SPRINT’s primary end-point, were used to weigh variables. Summary Scores (SS) were generated for each subject to scale with the Euclidean distance of participants from the theoretical "average patient" in six dimensional space.

A SS of 0.56 represents the 90th percentile and 0.74 represents the 97.5th. These were chosen as borders between the data-rich, data-limited, and data-free zones. SS were then calculated for 2007-14 NHANES participants with age >35, SBP≥130, and HbA1c<7. The NHANES population mapped onto SPRINT data zones shows a landscape of applicability by race and sex (Figure).

Defining data zones based on patient characteristics holds promise to refine the applicability of trial results.
Abstract P150: Sex Difference of Hypertension in Spontaneously Hypertensive Rats: Role of Mitochondrial Oxidative Stress
Authors: Maranon Rodrigo O , Dalmasso Carolina , Patil Chetal N , Reckelhoff Jane F
Published: July 2021

Men have higher blood pressure (BP) than premenopausal women. Pressor response to oxidative stress may be a major contributor to the sex difference in BP control. Mitochondrial oxidative stress is associated with hypertension; however, whether mitochondrial oxidative stress plays a role in the sex difference in BP is unknown. In the present study, we tested the hypothesis that mitochondrial oxidative stress contributes to the sex difference in BP regulation in spontaneously hypertensive rats (SHR). Young intact (iYMSHR) and castrated males (cYMSHR), and females SHR (YFSHR) (3 mos of age) were implanted with radiotelemeters, and after a 4 day baseline BP, were treated with mitoTempo (0.75 mg/kg/d, sc minipumps), a specific scavenger of mitochondrial superoxide, for 7 days. Following 10 days washout of mito-tempo, rats were treated with Tempol (30 mg/kg/day, po drinking water) for 7 days. iYMSHR have higher blood pressure (by telemetry) than cYMSHR and YFSHR (148±1 mmHg, n=5, vs 132±1 mmHg, n=5, and 139±1 mmHg, n=5; p<0.01, respectively). MitoTempo reduced BP by 6% in iYMSHR (147±1 vs 139±1, n=5; p<0.05) compared to females (3%: 139±1 vs 136±1; n=5; p: NS) and castrated males (4.5%: 132±1 vs 126±1, n=5; p<0.05). After 10 days washout, tempol reduced BP only in iYMSHR (144±1 vs 130±1 mmHg, n=5; p<0.05). Our results suggest that mitochondrial oxidative stress may contribute to BP regulation in male SHR, but has no effect in females. The data also suggest that the presence of testosterone is necessary for the pressor response to oxidative stress in males since Tempol had no effect on BP in castrated males. Further studies examining the effect of steroid hormones and mitochondria in BP regulation are necessary to elucidate the importance of mitochondrial oxidative stress on sex difference of hypertension.
Abstract P172: Methylation of Mitochondrial Genes and Mitochondrial Damage in Aged Kidney of Hypertensive Mice
Authors: Ren Lu , Sen Utpal , Pushpakumar Sathnur
Published: July 2021

Hypertensive nephropathy is a major global health issue. Accumulating evidence from recent studies suggest that mitochondrial injury may contribute to the pathogenesis of renal damage in hypertension leading to glomerular and tubular necrosis. It is well-known that aging is associated with declining mitochondrial function in several organ systems. However, the role of aging and its correlation with mitochondrial injury and kidney damage in hypertension remains unclear. The purpose of the present study was to determine whether methylation of mitochondrial genes contributes to mitochondrial dysfunction in the aged kidney in Ang-II induced hypertension. Wild type (WT, C57BL/6J) mice aged 12-14 wk and 75-78 wk were used in this study and treated without or with Ang-II (1000 ng/kg/min) for 4 weeks. In response to Ang-II, aged mice exhibited higher blood pressure (145.21±5.32 vs. 127.32±3.47 mmHg) and reduced glomerular filtration rate compared to young mice (362.7±8.3 vs. 825±10.2 μL/min/100 g b.w.). Ang-II upregulated DNA methyltransferases and increased Dnmt activity in aged kidney and bisulfite conversion and methylation specific PCR revealed increased methylation of mitochondrial superoxide dismutases 1 and 2 and Sirtuin-1 genes which correlated with lower protein levels suggesting impaired anti-oxidant defense. Aged mice exhibited reduced mitochondrial biogenesis as suggested by downregulation of peroxisome proliferator-activated receptor (PPAR)-α and -γ, and PPAR-γ-co-activator (PGC)-1α. Furthermore, reduction of optic atrophy 1 and mitofusin-2 indicated increased mitochondrial fragmentation and downregulation of ATP synthase was associated with impaired ATP generation in aged mice receiving Ang-II compared to young mice. Our results suggest that increased DNA methylation of mitochondrial antioxidant genes leads to oxidative stress induced mitochondrial damage in aged kidney during hypertension.
Abstract P183: Influence of Insufficient Sleep on Endothelial Fibrinolytic Capacity in Adults With Elevated Blood Pressure
Authors: Bain Anthony R , Dow Caitlin A , Diehl Kyle J , Bammert Tyler D , Greiner Jared J , Stauffer Brian L , DeSouza Christopher A
Published: July 2021

The capacity of the endothelium to release tissue-type plasminogen activator (t-PA) is impaired in adults with elevated BP, leading to an increased risk of thrombotic events. Insufficient sleep is independently associated with elevated BP and impaired t-PA release. However, the compounded influence of insufficient sleep on t-PA release in adults with elevated BP is unknown. We tested the hypothesis that impairments in the capacity of the endothelium to release t-PA in adults with elevated BP is worse in those who sleep <7 h/night (short sleep duration) compared with those who sleep 7 to 9 h/night (normal sleep duration). We studied 38 sedentary, middle-aged adults: 10 with normal BP and normal nightly sleep duration (6M/4F; age: 55±2 yr; BP: 114/94±2/3 mmHg, sleep duration: 7.4±0.2 h); 14 with elevated BP and normal nightly sleep duration (8M/6F; 60±2 yr; 141/87±2/2 mmHg; 7.8±0.1 h); and 14 with elevated BP and short nightly sleep duration (10M/4F; 57±2 yr; 139/85±2/2 mmHg; 6.1±0.2 h). All subjects were free of overt metabolic and coronary disease. Net endothelial release of t-PA was determined, in vivo, in response to intra-brachial infusions of bradykinin (BK: 125-500 ng/min) and sodium nitroprusside (SNP: 2.0-8.0 μg/min). In the normal sleep groups, as expected, endothelial t-PA release in response to BK was significantly blunted (~30%) in the adults with elevated BP (from -1.2±0.8 to 50.2±4.8 ng/100mL tissue/min) compared with normal BP (from 0.9±3.4 to 73.0±8.0 ng/100mL tissue/min); and total t-PA release (area under the BK curve) was ~25% lower (p<0.05) in the adults with elevated (307±33 ng/100mL tissue) vs. normal (396±27 ng/100mL tissue) BP. Importantly, net endothelial release rate (from -1.5±1.0 to 40.6±4.3 ng/100mL tissue/min) and total amount of t-PA released (222±28 ng/100mL tissue) in response to BK were markedly lower (~25% and 30%, respectively, P<0.05) in the elevated BP and short sleep duration group compared with the elevated BP and normal sleep duration group. In the elevated BP population, sleep duration was positively correlated with total t-PA release (r=0.46, P<0.05). There was no effect of SNP on t-PA release in any group. In summary, insufficient sleep is associated with exacerbated impairments in t-PA release in adults with elevated BP.
Abstract P190: Long-term Intake of Muscadine Grape Extract Markedly Improves Exercise Capacity in Older Female (mRen2)27 Hypertensive Rats
Authors: Duncan A’ja V , Graham Wayne , Yamaleyeva Liliya , Gallagher Patricia E , Tallant E. Ann A , Chappell Mark C , Diz Debra I
Published: July 2021

Muscadine grapes (
Vitis rotundifolia
) contain significant levels of polyphenols and their antioxidant capacity may have cardiovascular benefit. We determined the cardiovascular effects of a water soluble muscadine grape extract (MGE) from Piedmont Research & Development Corporation (PRDC, Winston-Salem, NC) that we confirmed has a high content of epicatechin, gallic acid, ellagic acid and procyanidin B2. We hypothesize that this soluble MGE with a potentially high phenolic bioavailability exhibits cardioprotective actions. The effect of long-term MGE intake on blood pressure, cardiac function and exercise tolerance was established in female and male hemizygous (mRen2)27 [mRen2] transgenic rats, an Ang II-AT
1
R-dependent model of hypertension. The mRen2 were administered MGE (8 mg of total phenolics/mL) in the drinking water for 26 weeks (7 female; 7 male); control rats (9 female; 11 male) were given water only. At 40 weeks of age, exercise tolerance was assessed by treadmill (10.2 m x min
-1
, 5% inclination). The MGE-treated female mRen2 exhibited a >300% improvement in workload (
W: g X m
) as compared to the untreated group [14551 ± 1313 vs. 4498 ± 481; p<0.01]. MGE intake also extended the time to fatigue (TTF) by 300% in females (4943 ± 443 vs.1615 ± 166 sec; p<0.01). In contrast, chronic intake of MGE had no effect on either exercise workload or TTF in the male mRen2. MGE intake did not alter systolic blood pressure in females (162 ± 3 vs. 166 ± 6 mm Hg, p>0.05) and males (165 ± 5 vs. 160 ± 3 mm Hg) nor alter body weight in either group [females: 334 ± 7 g vs. 339 ± 8 g; males: 613 ± 12 g vs. 590 ± 6 g). Echocardiographic analyses revealed that although the female mRen2 exhibited a higher ejection fraction [73.4±5.1 vs. 42.3±4.5%, n=4-5, p<0.05] and a higher fractional shortening [44.2±4.2 vs. 22.1±2.7%, n=4-5, p<0.05] as compared to males, MGE treatment did not improve these indices in either group. We conclude that the marked improvement in exercise capacity in older adult hypertensive females by chronic MGE intake is not accompanied by augmented cardiac performance, perhaps reflecting the lack of an effect on blood pressure. Thus, it is possible that MGE may directly impact the skeletal muscle to improve exercise in the hypertensive mRen2 females, but not the males.
Abstract P204: Gender-specific Relationships Between Plasma Levels of Endocannabinoids and Vagal and Sympathetic Control of Heart Rate in Normotensive Obese Older Adults
Authors: Schaich Chris L , Shaltout Hossam A , Kovach Alex , Grabenauer Megan , Thomas Brian F , Brinkley Tina E , Nicklas Barbara J , Diz Debra I
Published: July 2021

Previous studies in obese individuals indicate higher circulating endocannabinoids anandamide (AEA) and 2-arachidonoylglycerol (2-AG) than in lean counterparts. However, the association between plasma endocannabinoids and autonomic control of blood pressure and heart rate has not been assessed in obesity. In a sample of normotensive, obese older adults we analyzed plasma content of the endocannabinoids AEA and total AG using mass spectrometry and examined correlations with various indices of spontaneous sympathovagal activity. Spontaneous baroreflex sensitivity (BRS) for heart rate control was calculated by spectral analysis of arterial pressure (AP) time (Sequence [Seq] Up, Seq Down and Seq All) and frequency (low-frequency [LF] and high-frequency [HF] α) domains from continuous resting AP recordings. In addition, time domain analysis was used to calculate heart rate variability (HRV) and blood pressure variability, indices of cardiac vagal tone and vascular sympathetic tone, respectively. The sample included 8 males and 17 females with a mean age of 68.4 ± 0.6 years, a mean body mass index of 35.0 ± 0.8 kg/m
2
, and mean AP of 101.0 ± 2.2 mmHg. Across the complete sample, we report a significant inverse correlation between plasma AG content and HFα, an index of the vagally-mediated parasympathetic spontaneous BRS (
r
= -0.50,
P
< 0.05). We further report a significant inverse correlation between plasma AG and the vagal spontaneous BRS (Seq Up) in males (
r
= -0.87,
P
< 0.01) but not in females. However, in females but not males we found significant positive relationships between AEA and LFα, an index of sympathetic spontaneous BRS (
r
= 0.49,
P
< 0.05), and AEA and HRV (
r
= 0.50,
P
< 0.05). These results are consistent with a role for the endocannabinoid system to modulate autonomic control of the circulation in populations at risk for hypertension and cardiovascular disease, and suggest gender differences that have yet to be elucidated.
Abstract P217: Nox Compartmentalization, Protein Oxidation and ER Stress in Vascular Smooth Muscle Cells in Hypertension
Authors: Camargo Livia L , Montezano Augusto C , Harvey Adam , Tsiropoulou Sofia , Hood Katie , Cao Zhenbo , Burchmore Richard , Hartley Richard , Bulleid Neil , Touyz Rhian M
Published: July 2021

In hypertension, activation of NADPH oxidases (Noxs) is associated with oxidative stress and vascular dysfunction. The exact role of each isoform in hypertension-associated vascular injury is still unclear. We investigated the compartmentalization of Noxs in VSMC from resistance arteries of Wistar Kyoto (WKY) and spontaneously hypertensive rats (SHR). Expression of Nox1 and Nox4 was increased in SHR cells (96.6±28.7% and 48.2±21.2% vs WKY, p<0.05), as well as basal ROS levels measured by chemiluminescence (110.2±26.4% vs WKY, p<0.05) and amplex red (105.2±33.2% vs WKY, p<0.05). Phosphorylation of unfolded protein response activators, PERK and IRE1α, and expression of ER chaperone BiP were elevated in SHR cells (p<0.05 vs WKY), indicating activation of ER stress response. Immunoblotting after organelle fractionation demonstrated that Noxs are expressed in an organelle-specific manner, with Nox1, 2 and 4 present in plasma membrane, ER and nucleus, but not in mitochondria. In SHR cells, NoxA1ds (Nox1 inhibitor, 10μM) and GKT136901 (Nox1/4 inhibitor, 10μM) decreased AngII-induced ROS levels (p<0.001 vs Ctl). Additionally, mito-tempol (mitochondrial-targeted antioxidant, 50nM) and 4-PBA (ER stress inhibitor, 1mM) decreased basal ROS levels in SHR cells (p<0.05 vs Ctl). Furthermore, oxidation of the antioxidant enzymes Peroxiredoxins (Prx) was increased in SHRSP compared to WKY (2.51±0.14 vs 0.56±0.07, p<0.001). One-dimensional isoelectric focusing revealed that cytosolic Prx2 and mitochondrial Prx3 were more oxidized in SHRSP than WKY cells. Using a biotin-tagged dimedone-based probe (DCP-Bio) we identified oxidation of ER stress proteins BiP and IRE1. To investigate the effect of protein oxidation in vascular function, vascular reactivity was evaluated in isolated mesenteric arteries. Inhibition of general oxidation (DTT 1mM; Emax: 111.7±33.1) and peroxiredoxin (Conoidin A 10nM; Emax: 116.0±7.3) reduces vascular contraction in response to noradrenalin in WKY rats (Emax: 166.6±30.2; p<0.05). These findings suggest an important role for Nox1/4 in redox-dependent organelle dysfunction and post-translational modification of proteins, processes that may play an important role in vascular dysfunction in hypertension.
Abstract P248: Novel Role of Axl Kinase in Endothelial Cell Proliferation and Pulmonary Arterial Hypertension
Authors: Gorelova Anastasia , Sahoo Sanghamitra , Pagano Patrick J
Published: July 2021

Pulmonary arterial hypertension (PAH) is a poorly characterized disease of unclear etiology that affects individuals of all ages. Vascular remodeling and increase in pulmonary artery (PA) and right ventricle (RV) pressures are two major culprits in RV failure and death in PAH. Recent advances in the study of PAH suggest that endothelial cell proliferation is an early instigator of this hallmark remodeling. We postulated that Axl receptor tyrosine kinase (implicated in pro-proliferative and pro-survival signaling in cancerous cells) could mediate endothelial proliferation and thus hemodynamic changes occurring in PAH. Using immunofluorescent microscopy of lung microvessels of human PAH vs. non-PAH, we observed Axl expression on intimal endothelial cells but not medial smooth muscle cells. Furthermore, digitized microscopy revealed that Axl tended to increase on the endothelium of PAH vessels (1.65±0.15-fold vs. non-PAH; n=3-4;
p=0.057
). To address the role of Axl
in vivo
, an Axl inhibitor R428 was employed in a mouse model of pulmonary hypertension. C57Bl/6 mice were subjected to hypoxia at pO
2
=10% and VEGF receptor antagonist SU5416 (Su/Ch) or normoxia (Norm) for 3 wks. Indeed, Su/Ch caused a significant rise in lung Axl protein and mRNA (7.1±0.4- and 2.4±0.5-fold, Su/Ch vs. Norm, protein and mRNA, respectively; n=3-6; p<0.01). As predicted, RV pressure (RVP) rose from 27±0.5 to 43±1.8 mmHg (Norm vs. Su/Ch; n=6; p<0.01). However, we did not observe a decrease in RVP with twice-daily gavage of 75 mg/kg R428 (43±1.4 mmHg, Su/Ch + R428; n=6). A similar pattern was observed with mean PA pressure (18.4±0.3 and 28.7±1.2 mmHg, Norm vs. Su/Ch, p<0.01; 28.7±0.9 mmHg, Su/Ch + R428), RV resistance (1403±256 vs. 2703±464 Wood units, Norm vs. Su/Ch, n/s; vs. 3610±625 Wood units, Su/Ch + R428) and Fulton index (0.26±0.01 and 0.34±0.02, Norm vs. Su/Ch, p<0.05; 0.38±0.02, Su/Ch + R428). In conclusion, our preliminary results demonstrate upregulated Axl expression in the endothelium of PAH patients and in lungs of PH mice and suggest that Axl kinase may play a novel role in pulmonary vascular endothelial proliferation and remodeling in PAH. It remains to be determined whether drug bioavailability or severity of disease precluded an ameliorative effect of an Axl inhibitor.
Abstract P276: (Pro)Renin Receptor-dependent Renal Generation of Aldosterone Contributes to ENaC Activation During Angiotensin II-induced Hypertension
Authors: Wang Fei , Peng Kexin , Lu Xiaohan , Yang Kevin , Nau Adam , Yang Tianxin
Published: July 2021

(Pro)renin receptor (PRR) has emerged as a novel regulator of ENaC under various physiological and pathophysiological conditions including Ang II-induced hypertension. However, the mechanism for ENaC-activating action of PRR remains incompletely understood. The present study attempted to test renal-derived aldosterone (Aldo) as a potential mediator of PRR signaling in the setting of Ang II treatment. In normal Sprague-Dawley rats with intact adrenal glands, a 7-d minipump infusion of Ang II at 100 ng/kg/min induced a 3.2-fold increase in urinary Aldo excretion and a 1.8-fold increase in plasma Aldo, as assessed by ELISA. Following intramedullary delivery of a PRR decoy peptide PRO20 (120 μg/kg/d) (IM PRO20), Ang II-induced increases in urinary Aldo was reduced by 75% without affecting plasma Aldo, in parallel with attenuated hypertension (radiotelemetry-measured MAP on day 7: 132.6 ± 5.8 mmHg in Ang II+IMPRO20 vs. 157.1 ± 6.2 mmHg in Ang II). Following adrenalectomy (ADX), urinary Aldo was decreased from 9.3 ± 1.2 ng/24h to an unbeatable level under basal condition; it was elevated to 0.96 ± 0.05 ng/24h by Ang II and became undetectable again by IM PRO20, as assessed by mass spectrometry. Similar results were obtained by ELISA. In parallel, urinary Na+/K+ ratio in ADX rats was decreased by Ang II infusion and blunted by IM PRO20. Furthermore, Ang II infusion induced a 1.3-fold increase in urinary Aldo excretion and this increase was reduced by 60% in CD PRR KO mice, correlating to the changes in MAP. In cultured mpkCCD cells exposed to 10 nM prorenin, amiloride-sensitive transepithelial Na+ transport, measured by using epithelial volt-ohmmeter, was increased 2.1-fold at 6 h that sustained at 24 h, which was suppressed by 86% following treatment with the mineralocorticoid receptor antagonist eplerenone. Medium Aldo was increased by 2.6-fold following exposure to 10 nM prorenin for 24 h. Overall, these results suggest that activation of PRR results in local generation of Aldo that likely contributes to increased ENaC activity and thus hypertension during Ang II treatment.
Abstract P288: Systemic Administration of an Angiotensin Type-2 Receptor Agonist Decreases Renal Regulatory T Cells
Authors: Gillis Ellen E , Sullivan Jennifer C
Published: July 2021

There is increasing evidence supporting a critical role of the immune system in the development of hypertension. Our lab has previously reported sex differences in the renal T cell profile in both Spontaneously Hypertensive Rats (SHR) and Angiotensin II (Ang II) models of hypertension, with females having more anti-inflammatory regulatory T cells (Tregs) than males. Ang II has a well-defined role in the activation of pro-inflammatory T cells in hypertension via the angiotensin type-1 receptor (AT1R). Less is known about the role of the angiotensin type-2 receptor (AT2R) in the regulation of immune cells, although the AT2R has been shown to be cardioprotective and AT2R expression is greater in females than males. Based on the potential anti-hypertensive role of AT2Rs, we hypothesized that administration of an AT2R agonist, Compound 21 (C21), would increase renal Tregs, and this increase would be greater in females due to greater AT2R expression. Male and female SHR (10 weeks of age, n=3-4) were implanted with telemetry units for continuous monitoring of mean arterial pressure (MAP). Following 10 days of recovery, baseline MAP was recorded for 5 days. Rats were then divided into the following treatment groups: surgical controls, low dose C21 (150 ng/kg/min, sc by osmotic minipump), high dose C21 (300 ng/kg/min, sc by osmotic minipump). Kidneys were harvested after 2 weeks of treatment and flow cytometry was performed on whole kidney homogenates. MAP was not altered by C21 treatment in males (137±4 vs 134±4 vs 134±4 mmHg; n.s.) or females (128±2 vs 136±5 vs 134±4 mmHg; n.s.). Interestingly, despite having no effect on MAP, there was a significant decrease in renal CD3
+
CD4
+
FoxP3
+
Tregs in females following both low and high doses of C21 (data expressed as % CD3
+
CD4
+
cells: 6±0.6 vs 3±0.6 vs 3.5±1.3 %, respectively; p=0.02). Tregs decrease in males following the high dose of C21 only (data expressed as % CD3
+
CD4
+
cells: 3.3±0.3 vs 3.3±0.5 vs 1.7±0.7 %, respectively; p=0.05). Total CD3
+
T cells, CD3
+
CD4
+
T cells, and Th17 cells were not altered by C21 treatment. In conclusion, AT2R activation suppresses renal Tregs, and females are more sensitive than males. These data suggest a novel role for AT2R regulation in the kidney in hypertension.
Abstract P332: Dietary Salt Intake and Blood Pressure Control in Hypertensive Individuals Under Antihypertensive Treatment During 7 Years
Authors: Ohno Kazuto , Takase Hiroyuki , Machii Masashi , Nonaka Daishi , Sugiura Tomonori , Ohte Nobuyuki , Dohi Yasuaki
Published: July 2021

Purpose:
Excess salt intake is one of the most important causes of hypertension. Salt restriction is a key strategy in the management of hypertension and, thus, should be instructed for hypertensive patients under medical treatment. We investigated recent changes in dietary salt intake and blood pressure (BP) levels in hypertensive patients.

Methods:
Total of 12422 hypertensive subjects (male 71.0% [8814 of 12422], 64.6±9.2 year-old) under medical treatment who visited our hospital for a physical checkup from 2010 to 2016 were enrolled. They were divided into 3 groups according to the number of antihypertensive drugs prescribed (1, 2 and ≥3 drugs). Cross-sectional analyses were performed using data in each year and changes during the 7 years were investigated. Individual salt intake was estimated using a spot urine by a previously reported method.

Results:
BP levels and the accomplishment rate of the target BP (<140/90mmHg) were improved in each group during the 7 years without significant difference among the groups (Overall 2010 to 2016; BP 132.7±13.6/80.0±8.9 to 128.8±13.7/76.3±9.6 mmHg and accomplishment ratio 65.6 [968 of 1475] to 76.4% [1433 of 1875]). However, individual salt intake was gradually increased in all groups (2010 to 2016 in 1, 2, and ≥3 drugs; 11.7±3.7 to 12.2±4.0, 11.9±3.7 to 12.7±3.9, and 12.2±3.9 to 12.9±4.1 g/day, respectively) and the accomplishment rate of salt restriction (<6g/day) was significantly reduced in subjects with increased number of antihypertensive drugs (3.5 [225 of 6435], 2.8 [125 of 4564], and 2.3% [33 of 1423] in groups with 1, 2, and ≥3 drugs, respectively). The accomplishment rate of the target BP was significantly higher in patients who achieved salt restriction than in those who did not achieve salt restriction in all groups (Over all; 80.2 [307 of 383] vs. 73.3% [8829 of 12039]).

Conclusions:
The control of BP in individuals with antihypertensive medications was improved in the last 7 years. However, salt restriction has not been successfully achieved especially in hypertensive patients with multiple antihypertensive medications. Excess salt intake may induce resistance to antihypertensive treatment and, thus, increases the number of antihypertensive drugs for BP control.
Abstract P337: Sodium-independent Elevations of Blood Pressure are Accompanied by Immune Cell Infiltration in the Kidney and Renal Damage in Dahl SS Rats
Authors: Wade Brittany M , Mattson David L
Published: July 2021

Infiltration of immune cells in the kidney is driven by elevated renal perfusion pressure and amplifies sodium-sensitive hypertension and renal injury in Dahl Salt Sensitive (SS) rats fed a high salt diet. The present studies were performed to determine the importance of immunity in the development of sodium-independent hypertension and renal damage in SS rats and SS lacking T- and B-lymphocytes due to a null mutation in the Rag1 gene (SS-Rag1

em1Mcwi

). The baseline level of mean arterial pressure (MAP) was not different between groups, and the continuous infusion of AngII (5 ng/kg/min, iv) to SS and SS-Rag1

em1Mcwi

fed low salt (0.4% NaCl) led to a significantly greater increase in MAP in SS (190±3 mmHg) than in SS-Rag1

em1Mcwi

(177±3 mmHg) after 12 days of infusion (n=9 rats/group). Renal damage, as assessed by albumin excretion rate, was significantly increased after 12 days of AnglI infusion in the SS (from 32±4 to 81±9 mg/day) and in the Rag1 mutants (from 12±2 to 51±8 mg/day). Compared to vehicle-infused rats, kidneys of AngII-treated SS (n=4-5/group) had increased CD45+ total leukocytes (1.8±0.2 vs 4.4±1.2 x 10
6
cells/kidney), including CD11b/c+ macrophages/monocytes and CD3+ T Cells. Upon cessation of the AngII infusion, MAP in the SS-Rag1

em1Mcwi

significantly decreased to a level not different from control values (135±5 vs 128±3 mmHg). In contrast, though MAP decreased in the SS when AngII infusion was stopped, blood pressure remained at a level greater than control values throughout the 9-day recovery period (157±8 vs 129±2 mmHg). Albumin excretion rate also tended to decrease in both SS and SS-Rag1

em1Mcwi

rats following the return to saline infusion, but the reversibility was not complete. Despite the maintenance of elevated pressure in the SS following AngII withdrawal, there was a significant and complete reversal in the number of CD45+, CD11b/c+, and CD3+ cells in the SS kidneys. The present data indicate that immune cells amplify sodium-independent hypertension and the development of renal damage in the SS rat, but also indicate that factors in addition to renal perfusion pressure may mediate immune cell infiltration into the kidney in hypertension.
Abstract P343: A Dual Endothelin A/B Receptor Blocker in a Rat Model of Sleep Apnea and Chronic Kidney Disease
Authors: Gonzalez Bosc Laura V , Giermakowska Wieslawa , Pace Carolyn E , Barrera Adelaeda , Mendiola Perenkita , Jones David T , Murphy Minerva , Kanagy Nancy L
Published: July 2021

Obstructive sleep apnea (OSA) is characterized by recurrent episodes of pharyngeal collapse during sleep resulting in intermittent hypoxia (IH) and sleep fragmentation. OSA affects 5% to 20% of the US population, is associated with high incidence of hypertension, and is a prognostic indicator of accelerated renal failure. More than 20 million people in the US have chronic kidney disease (CKD). In rodents, endothelin-1 (ET-1) contributes to IH-induced hypertension, and ET-1 levels inversely correlate with GFR in end-stage CKD patients. These findings provide the rationale to test the hypothesis that a dual ET receptor antagonist will attenuate the development of hypertension and renal dysfunction in a combined rat model of IH and CKD. Male Sprague Dawley rats received one of three diets: A) control, B) 0.2% adenine, C) 0.2% adenine + 30 mg/kg/day of macitentan (dual ET
A
/ET
B
receptor antagonist, Actelion Pharmaceuticals) for 2 weeks followed by 2 weeks of recovery (regular chow or chow+macitentan). Rats were then exposed to sham or IH (20 short exposures/hr to 5% O
2
and 5% CO
2
7 hr/day during sleep) for 4 weeks. Changes in mean arterial blood pressure (MAP) recorded by telemetry are in
Figure 1A
and estimated glomerular filtration rate
in Figure 1B
. In summary, macitentan prevents increases in blood pressure caused by CKD, IH and by the combination of CKD+IH. However, it does not improve kidney function. Our data suggest that macitentan could be an effective antihypertensive in CKD patients with irreversible kidney damage as a way to protect the heart, brain and eyes from elevated arterial pressure but it does not reverse toxin-induced tubule atrophy in our experimental conditions.
Abstract P384: Switching Insufficient Hypotensive Monotherapy to ARB and CCB Combination Tablet in Elderly Patients Increases Both Patient and Physician Satisfaction Rates and Contributes Better Patient-physician Concordance
Authors: Ikeda Yoshiyuki , Sasaki Takeshi , Kuwahata So , Akasaki Yuichi , Hamada Chikuma , Ohishi Mitsuru
Published: July 2021

Background:
Treatment must take into consideration patient-physician concordance conducted with good communication. Whereas it has been reported that there are discrepancies in awareness between patients and physicians regarding the blood pressure (BP) levels, there are no studies addressing patient and physician satisfaction with hypertension (HT) treatment. Reducing the pill burden and medication costs using combination drug, such as ARB/CCB tablet might improve adherence and concordance. Thus, the aim of this study is to evaluate the satisfaction of both hypertensive elderly patients and their physicians and QOL of patients with angiotensin II type I receptor blocker (ARB) and calcium channel blocker (CCB) combination drug (CD) treatment.

Methods and Results:
An open-label, multicenter, intervention study was conducted. Patients with insufficient hypotensive effect under the treatment with ARB or CCB monotherapy were enrolled, and medication was switched to CD and taken for 12 weeks. Physicians and patients participated in satisfaction surveys concerning HT treatment and patients also participated in QOL survey. Both home and clinic BP measurements showed a significant decrease after treatment was switched to an CD. Patient satisfaction rates showed an increase for treatment (69.4% to 90.1%), antihypertensive drugs (60.0% to 76.5%), clinic BP (37.0% to 68.8%), and home BP (41.2% to 67.5%). Significant differences were found between patients and physicians in the proportions of satisfaction and dissatisfaction at baseline, and ratios for both patient and physician satisfaction increased at 12 weeks. The QOL survey for patients showed significantly increase in the QOL score for general health (p = 0.0191). After CD treatment, satisfaction rates for both patients and physicians increased and improvement in the discrepancy between patient and physician satisfaction was achieved in addition to better BP control.

Conclusions:
In elderly patients with HT, switching insufficient hypotensive monotherapy to ARB and CCB combination tablet treatment increases both patient and physician satisfaction rates and contributes better patient-physician concordance.
Abstract P389: Post-traumatic Stress-induced Sensitization of Angiotensin II Hypertension is Reversed by Blockade of Angiotensin-converting Enzyme or Tumor Necrosis Factor-alpha
Authors: Xue Baojian , Yu Yang , Wei Shun-Guang , Beltz Terry G , Guo Fang , Felder Robert B , Johnson Alan K
Published: July 2021

Using an Induction-Delay-Expression experimental paradigm, our previous studies demonstrated that post-traumatic stress disorder (PTSD) sensitizes angiotensin (ANG) II-elicited hypertension, which was associated with upregulation of central renin-angiotensin system (RAS) components and proinflammatory cytokines (PICs). The present study investigated whether inhibition of angiotensin-converting enzyme (ACE) or tumor necrosis factor-α (TNF-α) prior to PTSD blocks sensitization of ANG II-elicited hypertensive response. The resident-intruder paradigm was used to model PTSD. Each intruder rat (male Sprague-Dawley) was pretreated with ACE inhibitor (captopril, 0.5 mg/Ml) or with TNF-α inhibitor (pentoxifylline, PTX, 100 mg/kg/day) in the drinking water for two weeks and then exposed to a different resident (male Long-Evans) for 2 hours on three days with each session separated by 1 day. Beginning 3 days after the last exposure, the intruder (PTSD) rats and unstressed control rats received a subcutaneous infusion of ANG II (120 ng/kg/min) for 2 weeks. The PTSD rats had a significantly enhanced hypertensive response to the ANG II infusion and an upregulation of mRNA expression of RAS and PIC components and of a microglial marker in the lamina terminalis (LT) when compared to control rats. Both the sensitized hypertensive response and enhanced gene expression were blocked by pre-treatment with either ACE inhibitor or TNF-α antagonist. These results suggest

that upregulation of the brain RAS and PICs produced by a severe stress contribute to PTSD-induced sensitization of the hypertensive response to ANG II.
Abstract P402: Familial Clustering of Hypertensive Target Organ Damage in the Community
Authors: Niiranen Teemu J , Lin Honghuang , Larson Martin G , Vasan Ramachandran S
Published: July 2021

Prior studies suggest that hypertensive target organ damage (TOD) is a heritable trait. However, the risk that parental TOD confers on propensity for TOD in their offspring, and how hypertensive TOD clusters in the background of parental versus offspring hypertension status remain unclear. We studied 3238 Framingham Heart Study participants (mean age 39±8 years, 53% women) with available parental data on TOD. Parents and offspring underwent measurements for echocardiographic left ventricular hypertrophy, microalbuminuria, and conventional risk factors. Prevalence of any TOD (left ventricular hypertrophy or microalbuminuria) in participants with 0 and ≥1 parents with any TOD was 7% (131 of 1860) and 13% (173 of 1378), respectively (
P
<0.001 for difference). As illustrated in the
Figure
, having ≥1 parent with TOD was associated with greater odds of TOD in offspring compared to individuals without parental TOD (multivariable-adjusted odds ratio [OR], 1.65; 95% confidence interval [CI], 1.27-2.14). Similarly, parental left ventricular hypertrophy was associated with offspring left ventricular hypertrophy (OR, 2.73; 95% CI 1.92-3.89) and parental albuminuria was related to offspring albuminuria (OR, 1.49; 95% CI 1.03-2.16). These associations remained robust upon additional adjustment for risk factors and in analyses of subgroups defined according to parental or offspring hypertension status (
Figure
). Overall our data suggest that familial clustering of TOD in the community is independent of blood pressure. Additional studies are warranted to confirm our observations.
Abstract P409: Defective Renal Ang III and AT2 Receptor Signaling in Pre-hypertensive Spontaneously Hypertensive Rats (SHR)
Authors: Kemp Brandon A , Howell Nancy L , Padia Shetal H , Keller Susanna R , Gildea John J , Carey Robert M
Published: July 2021

The intrarenal renin-angiotensin (RAS) system controls blood pressure and electrolyte balance. Angiotensin II (Ang II), the principal RAS effector peptide, is metabolized by aminopeptidase A to des-apartyl
1
-Ang II (Ang III). Our previous studies showed that Ang III, not Ang II, is the preferred endogenous agonist for Ang type-2 receptor (AT
2
R)-induced natriuresis in normal rats, and that hypertensive 12-week old SHR lack natriuretic responses to Ang III. The present study tested whether Ang III induced natriuresis in 4 week old pre-hypertensive SHR by activating/translocating intrarenal AT
2
Rs and internalizing the major renal proximal tubule (RPT) sodium transporter NHE-3. Female 4 week old SHR (N=6) and WKY (N=6) rats were studied after 24 h systemic AT
1
R blockade with candesartan. The left kidney received a 30 min renal interstitial (RI) infusion of vehicle followed by cumulative RI infusions of Ang III (3.5, 7.0, 14, and 28 nmol/kg/min; each dose for 30 min). The right kidney received vehicle RI infusions. In 4 week old WKY, RI Ang III increased urine sodium excretion (U
Na
V) dose dependently from control of 0.04 ± 0.01 to 0.08 ± 0.02 (P<0.05), 0.09 ± 0.02 (P<0.01), 0.07 ± 0.01 (P<0.05), and 0.07 ± 0.01 (P<0.05) μmol/min. In 4 week old pre-hypertensive SHR, RI Ang III failed to induce natriuresis at all doses except 28 nmol/kg/min (0.03 ± 0.01 vs. 0.05 ± 0.01 μmol/min; P<0.05). There was no change in U
Na
V in right control kidneys of WKY or SHR. Also, Ang III had no effect on mean arterial pressure (MAP) in WKY or SHR. However, MAP was slightly higher, but normotensive, in SHR than WKY. Control and Ang III infused kidneys were processed for confocal microscopy from a separate group of rats. In WKY, RI Ang III induced translocation of AT
2
Rs from subapical to apical membranes of RPT cells [RPTC] (1767 ± 41 vs. 1313 ± 47 RFU; P<0.001). Simultaneously, Ang III induced retraction of NHE-3 from in SHR, intrarenal Ang III failed to induce AT
2
R translocation, NHE-3 retraction, and pSer
552
-NHE-3 upregulation. These results apical to subapical membranes of RPTCs (1703 ± 90 vs. 1388 ± 91 RFU; P<0.05). Consistent with NHE-3 retraction, Ang III increased pSer
552
-NHE-3 (1102 ± 57 vs. 830 ± 66 RFU; P<0.01). In contrast,demonstrate defective Ang III and AT
2
R signaling in pre-hypertensive SHR.
Abstract P415: ACE N-domain Regulates High-glucose Mediated Interleukin-1 beta Production by Renal Epithelial Cells Independently From Angiotensin II Generation
Authors: Giani Jorge F , Bernstein Ellen A , Eriguchi Masahiro , Gonzalez-Villalobos Romer A , Bernstein Kenneth E
Published: July 2021

Research studies demonstrated that interleukin (IL)-1β contributes to the development of diabetic nephropathy and hypertension. However, the origin and regulation of IL-1β synthesis during diabetic kidney injury are still unknown. Here, we hypothesize that renal epithelial cells produce IL-1β in response to a high glucose stress and that angiotensin converting enzyme (ACE) plays a key role in this process. To study this, we isolated proximal tubular (PT) epithelial cells from wild-type (WT) and mice lacking either the ACE N-domain (NKO) or the C-domain (CKO) catalytic activity. These cells were exposed to normal (5 mM) or high (30 mM) glucose for 24 hours. IL-1β produced by PT cells were assessed by ELISA and RT-PCR. High glucose induced WT PT cells to release significant amounts of IL-1β (from 5±1 to 70±6 pg/ml, p<0.001; n=6). When WT PT cells were exposed to a high glucose media in the presence of an ACE inhibitor (lisinopril, 10 mM), IL-1β levels were significantly reduced (from 70±6 to 38±6 pg/ml, p<0.01). In contrast, AT1 receptor blockade by losartan did not change the amount of IL-1β produced by WT PT cells. To determine which ACE domain is associated with IL-1β production, NKO and CKO PT cells were exposed to high glucose. Strikingly, NKO PT cells released lower amounts of IL-1β when exposed to high glucose compared to WT (NKO: 15±7 vs. WT: 79±9 pg/ml, p<0.01, n=4). No differences were observed between WT and CKO PT cells. Since the ACE N-domain degrades the anti-inflammatory tetrapeptide N-acetyl-Ser-Asp-Lys-Pro (AcSDKP), we tested whether the lower IL-1β production in NKO PT cells was due to an accumulation of AcSDKP. For this, we pre-treated NKO PT cells with a prolyl endopeptidase inhibitor (S17092, 50μM) to prevent the production of AcSDKP. Notably, this treatment increased the IL-1β response to high glucose in NKO PT cells (2.1±0.3-fold increase, p<0.01, n=4). Our data indicate that: 1) PT cells can sense and respond to high glucose by secreting IL-1β and 2) the absence of the ACE N-domain blunts the production of IL-1β through a mechanism that involves AcSDKP accumulation. In conclusion, ACE might contribute to the inflammatory response that underlays diabetic nephropathy independently from angiotensin II generation.