bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 390: Cardiovascular Effects of the Angiotensin-(1-7) Analogue A1317
Authors: Braga Janaina F , Caldeira Neiva , Lautner Roberto Q , Fraga-Silva Rodrigo A , Santos Robson A
Published: July 2021

Angiotensin-(1-7) (Ang-(1-7)) has been shown to have anti-hypertensive properties mediated through the receptor
Mas
. The beneficial effects of the Mas/Ang-(1-7) pathway prompted us to develop Ang-(1-7) analogues and peptides ligands for Mas. In the present study we evaluated the vasorelaxant and anti-hypertensive effect of the analogue A1317. To examine the NO production, chinese hamster ovary (CHO) cells transfected with
Mas
cDNA were incubated with A1317 at 10
-7
and 10
-6
mol/l for 60 minutes. Subsequently, the slices were mounted for evaluation by confocal microscopy. The vasorelaxant activity of the A1317 was measured in rings from Wistar rats and spontaneously hypertensive rats (SHR) descending thoracic aorta with functional endothelium pre-contracted with phenylephrine (0.1μM). To determine which receptor is involved in the vasorelaxant effect of the peptide experiment was performed in the presence of the Ang-(1-7) antagonist, A-779 (10 μm), in SHR rings. The acute effect of the peptide on arterial pressure was evaluated in male normotensive Wistar rats and SHR. Mean arterial pressure (MAP) and heart rate (HR) were monitored for 5 hours after
in
bolus
administration of different doses of A1317 (0.1-12.5nmol/kg) in conscious animals. A1317 stimulated the NO production in CHO-Mas transfected cells and produced a concentration-dependent vasodilator effect in endothelium-containing aortic rings (Emax=18.97±1.33% in Wistar rings and 38.0±3.3% in SHR rings). The vasorelaxation produced by A1317 was attenuated by A779. Acute administration of A1317 reduced the MAP time and dose-dependently in conscious SHR. The reduction in MAP started to be significant after 130 minutes of the
in bolus
injection (Δ=-13±2.0mmHg; 0.5nmol/kg). The maximum change in MAP was observed after 4 hours of the
in bolus
injection (Δ=-21±4.0mmHg;

0.5nmol/kg). A1317 also produced a decrease in MAP of normotensive Wistar rats, however the magnitude of the MAP change was considerably smaller than that observed in SHR (Δ=-8.8±2.0mmHg). There was no significant effect of A1317 on HR of Wistar rats or SHR. These data suggest that the peptide A1317 presents antihypertensive and vasorelaxant properties and may have cardiovascular applications similar to those of Ang-(1-7).
Abstract 40: Renin is Produced By a General Lysosomal Degradation Mechanism
Authors: Xa Lucie K , Lacombe Marie-Josée , Mercure Chantal , Reudelhuber Timothy
Published: July 2021

Renin is secreted almost exclusively by the juxtaglomerular (JG) cells of the kidney where it is first made as an inactive precursor called prorenin. Conversion of prorenin to active renin requires the proteolytic removal of an N-terminal prosegment by a second protease whose identity is still debated. Active renin is then stored in dense vesicles and secreted in response to stimuli. Using confocal microscopy we found that C57BL6 mouse kidney JG cells are highly enriched in Lamp-1, a biomarker for lysosomes, and that renin and Lamp-1 co-localize in renin storage vesicles. These data suggest that renin is stored in secretory lysosomes. N-terminal sequencing of C57BL6 mouse Ren-1 renin purified from kidney revealed an N-terminus beginning with SPVVLT¼. This is the same amino terminus as that reported for rat renin and mouse As4.1 cells and different from that reported for human renin. This result raises the possibility that rodents and humans use different prorenin processing enzymes (PPE). Treatment of mice with captopril for 7 days increases plasma active renin by 19-fold (control 149 +/- 22 vs. treated 2859 +/- 672 ng AI/ml/hr, P< 0.0001) and kidney renin messenger RNA by 4.81-fold (P< 0.0001). Nevertheless, Illumina expression array analysis of C57BL6 mouse kidney before and after captopril treatment did not reveal candidate PPEs whose expression paralleled that of renin. This result suggests that the PPE is not limited to JG cells. To test the possibility that general lysosomal hydrolases are responsible for renin production, we used a Lamp-1 C-terminal sequence to force the sorting of mouse Ren-1 prorenin into lysosomes of transfected human embryonic kidney (HEK) cells. Transfection resulted in the intracellular retention of renin of the appropriate molecular weight and which lacked the engineered Lamp-1 C-terminal tail, suggesting that the proteolytic processing of prorenin is not carried out by a protease that is restricted to JG cells. Altogether, our results are consistent with mature renin being produced by lysosomal degradation of the prosegment and the selective resistance of mature renin to hydrolysis. The different N-termini of rodent and human renins could be explained by differential susceptibility of their prosegments to lysosomal hydrolysis.
Abstract 411: Cytokine Receptors in the Subfornical Organ Mediate Sympathetic and Hemodynamic Responses to Peripherally Administered TNF-α and IL-1β in Rat
Authors: Wei Shun-Guang , Beltz Terry G , Zhang Zhi-Hua , Yu Yang , Johnson Alan K , Felder Robert B
Published: July 2021

Introduction:
Pro-inflammatory cytokines (PIC) play an important role in regulating autonomic and cardiovascular function in hypertension (HTN) and heart failure (HF). Peripherally administered PIC such as tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) act within the brain to increase blood pressure (BP), heart rate (HR) and renal sympathetic nerve activity (RSNA). These molecules are too big to cross blood brain barrier (BBB), and so the mechanisms by which they activate sympathetic drive to elicit hemodynamic responses remain quite a mystery. Our preliminary data indicate a dense distribution of TNF-α and IL-1β receptors in the subfornical organ (SFO), a forebrain which lacks a BBB and can be accessed readily by circulating PIC. The SFO projects to the hypothalamic paraventricular nucleus, which has been implicated as an important source of cardiovascular and autonomic dysfunction in HTN and HF.

Hypothesis:
SFO neurons sense circulating PIC and mediate their effects on sympathetic drive and hemodynamic responses.

Methods:
One week after an SFO lesion or a sham lesion (SHAM), urethane anesthetized male SD rats underwent an intracarotid artery (ICA) injection of TNF-α (200 ng) or IL-1β (200 ng). BP (mmHg), HR (beats/min) and RSNA (% change) responses were recorded.

Results:
In SHAM rats (n=5), ICA TNF-α dramatically increased (* p<0.05 vs. baseline) the BP (23 ± 1.5*), HR (61 ± 5*) and RSNA (88.5 ± 4.3 %*) responses, which peaked ∼30 min after injection. These early excitatory responses to ICA TNF-α were absent in SFO-lesioned rats (n=5), though a moderate excitatory response occurred hours later. Similarly, ICA IL-1β elicited increases in BP (21.8 ± 2.1*), HR (62 ± 6*) and RSNA (116.5 ± 5.2*) in the SHAM rats (n=5). In the SFO-lesioned rats (n=5), the BP (8.6 ± 1.3 †), HR (24 ± 2 †) and RSNA (26.8 ± 1.6 †) responses to ICA IL-1β were significantly († <0.05 vs. SHAM) attenuated.

Conclusion:
These data suggest that the SFO plays an important role as a central nervous system sensor of the peripheral inflammatory state, mediating the effects of circulating PIC on sympathetic drive and cardiovascular function in inflammatory conditions such as HTN and HF. The later occurring excitatory responses to PIC are unexplained but may involve their known vascular effects.
Abstract 418: Mineralocorticoid Receptor in Nucleus of the Solitary Tract Contributes to Aldosterone Stimulation of Salt Intake
Authors: Mifflin Steve W , Cherry Brandon , Franzke Michelle , Koneru Bhuvaneswari
Published: July 2021

A group of neurons in the nucleus of the solitary tract (NTS) contains the mineralocorticoid receptor (MR) which makes these neurons candidates for stimulating salt intake in response to aldosterone. The purpose of this study was to determine if neurons within the NTS that possess the MR play a role in aldosterone stimulation of salt intake. Five adult WKY rats received microinjections into the NTS of a small, hairpin RNA (shRNA) for the MR (Genedetect, Inc.) and 5 rats received NTS injections of a scrambled RNA (scRNA). In each rat injections of viral constructs were made at 3 points, all 0.5mm below the surface of the brain: calamus; bilaterally at 0.5mm rostral to calamus and 0.5mm lateral to the midline. One week after the viral construct injections, aldosterone-filled osmotic mini-pumps were implanted subcutaneously and connected to tubing within the 4
th
ventricle to infuse aldosterone at a rate of 20ng/h. Prior to and after surgeries, rats had ad libitum access to food and two graduated drinking bottles filled with distilled water and 0.3M NaCl respectively. Fluid level within each bottle was measured at the same time every day and salt intake expressed as 100 X the ratio of 0.3M NaCl intake to total fluid intake. Previous studies indicate that the viral constructs require 2 weeks to have a discernible effect. One week after injection of the viral constructs and prior to infusion of implantation of the aldosterone mini-pump, salt intake in shRNA injected rats was 6% ± 3% and in scRNA injected rats it was 4% ± 2%. One week after beginning aldosterone infusion (two weeks after injection of viral constructs), salt intake in shRNA injected rats was 16% ± 5% and in scRNA injected rats it was 22% ± 7% (p=0.01). Three weeks after beginning aldosterone infusion, salt intake in shRNA injected rats was 5% ± 2% and in scRNA injected rats it was 14% ± 9% (p=0.01). Post-mortem immunohistochemistry revealed a significant reduction in the number of NTS neurons exhibiting immunoreactivity for the MR (shRNA 2 ± 2 cells/section; scRNA 12 ± 2 cells/section; p=.008). These results indicate hindbrain infusions of aldosterone stimulate salt intake and that at least part of the hindbrain aldosterone stimulation of salt intake are mediated by hindbrain NTS neurons that possess the MR.
Abstract 424: Fish Oils Reduce the Risk of Stroke in Patients with Hypertension
Authors: Zhang Li , Mudumbi Praveen , Beer Dominik , Day Roseann , Robinson Victoria M , Ghosh Pradeepto , Esberg Douglas B , Rothman Steven A , Kramer R. Kyle , Day Francis , Kowey Peter R
Published: July 2021

BACKGROUND:
Hypertension (HTN) is a major cause of stroke. Previous studies showed evidence that long term fish oil consumption can prevent stroke in men but it has not been thoroughly investigated in patients with HTN. This study aimed to determine the prevalence of stroke or transient ischemic attack (TIA) in HTN patients consuming fish oils.

METHODS
Medical records of HTN patients were retrieved randomly from two hospital based cardiology outpatient clinics. The prevalence of stroke/TIA was investigated in patients with and without taking fish oils and the compliance of fish oil intake was further investigated by a follow-up survey. The use of anticoagulant agents, angiotensin-converting enzyme inhibitors (ACE), angiotensin receptor blockers (ARBs) and beta-blockers (BB) was also compared between two groups.

RESULTS
After taking fish oils (2±1 g) daily for a median duration of 4 yrs (95% CI: 3, 5 yrs) none of HTN patients in the fish oil group developed stroke/TIA whereas events of stroke/TIA occurred in 8% of HTN patients in the non-fish oil group (Table 1). No difference was found in the concomitant use of ACE, ARBs and BB in the two groups and the effect of fish oil was not influenced by anticoagulants.

CONCLUSIONS:
Our findings suggest that long term fish oil consumption can reduce the risk of stroke in patients with hypertension. This simple approach may help reduce the healthcare burden and improve the quality of life by preventing stroke in patients with hypertension.
Abstract 439: Gender Bias in Prehospital Chest Pain Management: Do female Paramedics Under-treat patients With Chest Pain?
Authors: El Sanadi Nabil , Leduc Todd , Erdman David , Mansour Jason , Thornton Gabriel
Published: July 2021

Introduction:
Patients with possible coronary insufficiency should undergo aggressive treatment to minimize the pain, since chest pain is a correlate of myocardial ischemia and injury. Patient gender should not affect the intensity of therapy.

METHODS:
A retrospective run-sheet review from a large prehospital system (684 paramedics E.M.S. approximately 17,000 runs/year) was done to determine the gender of the lead paramedic, the gender of the patient and the chest pain score difference pre-and post-treatment. Treatment included standard therapy of oxygen, nitroglycerin and morphine. A pain score of 0-10 was used. All runs with “chest pain” as the chief complaint were reviewed from 4/2007 to 7/2008. 225 cases were found. 2 sample poison test was used to analyze the data.

Results:

When female E.M.T.P’s treat female patients vs. Treating male patients, the pain score difference is 1.77 (p=0.010) When male E.M.T.P’s treat male patients vs. Female patients the pain score difference is 0.57 (p=0.063)

Conclusions:
Female FF/EMTP treat female patients more aggressively for chest pain than when they treat male patients. This may be due to gender bias and expectation of pain tolerance by male patients. Male FF/EMTP treats male and female patients with the same intensity.
Abstract 44: Restoration of Angiogenic Balance and Improved Endothelial Cell Function via Ampk Activation is Hypoxia and Ischemia Dependent in Trophoblast Cells and Pregnant Rats
Authors: Banek Christopher T , Bauer Ashley J , Needham Karen M , Dreyer Hans C , Gilbert Jeffrey
Published: July 2021

Previous studies indicate restoration of angiogenic balance lowers blood pressure and improves vascular endothelial cell function in several experimental models of preeclampsia. Stimulation of the adenosine monophosphate kinase (AMPK) pathway is known to increase VEGF expression. We hypothesized stimulation of AMPK with aminoimidazole carboxamide ribonucleotide (AICAR) would increase plasma VEGF, improve endothelial cell (EC) function and attenuate reduced uterine perfusion pressure (RUPP)-induced hypertension. RUPP was induced on day 14 of gestation (term=21), AMPK activation was stimulated
in vivo
by AICAR administered i.p. (50mg/kg) twice daily. Arterial pressure (AP) and tissues were collected on day 19. Human derived trophoblast cells were cultured in physiologic normoxic (8% O
2
) and hypoxic (1.5% O
2
) conditions. Angiogenic balance and EC function were assessed with an endothelial tube formation assay using human umbilical vascular endothelial cells (HUVEC) cultured for 8h with 5% serum from each treatment group. AICAR increased (
P
<0.05) placental phosphorylation of AMPKα in RUPP+AICAR (0.33±0.06) compared to normal pregnant (NP), NP+A and RUPP rats (0.19±0.03
vs.
0.16±0.04
vs.
0.18±0.03). AICAR increased (
P
<0.05) free plasma VEGF in the RUPP+AICAR (884±128 pg/ml) compared to NP+AICAR, NP and RUPP rats (708±179
vs.
843±52
vs.
420±75 pg/ml). EC function as assessed by tube formation was decreased by treatment with serum from RUPP
vs
. NP (25±2 vs. 51±7; tubes/frame;
P
<0.05) rats and this deficit was abrogated with serum from RUPP+AICAR rats (86±9 tubes/frame;
P
<0.05). RUPP hypertension was mitigated by AICAR infusion (NP 95±3; RUPP 123±2; NP+AICAR 104±3; RUPP+AICAR 101±5mmHg;
P
<0.05). Hypoxia increased (
P
<0.05) VEGF secretion 30% by BeWo cells and this effect was augmented a further 60% (
P
<0.05) by treatment with the AICAR mimetic metformin. AICAR increased levels of placental AMPK activation, increased free VEGF concentrations in plasma, restored endothelial cell function and reduced blood pressure RUPP rats but had no effect on these measures in NP control rats. These findings show AMPK activation and stimulation of VEGF with AICAR is ischemia/hypoxia dependent and may be useful for management of hypertension in pregnancy.
Abstract 445: Effects of Aerobic Exercise Training on C-Reactive Protein Levels in Normotensives versus Non-Normotensives
Authors: Kretzschmar Jan , Feairheller Deborah L , Sturgeon Kathleen , Diaz Keith M , Williamson Sheara T , Veerabhadrappa Praveen , Ling Chenyi , Perkins Amanda , Grimm Heather , Lee Hojun , Babbitt Dianne , Crabbe Deborah L , Kashem Abul M , Brown Michael D
Published: July 2021

One of the precursors to hypertension (HTN) is systemic inflammation which can lead to vascular dysfunction and eventually HTN. Aerobic exercise training (AEXT) is known to be an important intervention tool in the prevention and treatment of HTN, inflammation and vascular dysfunction. However, no study has yet determined the effect of AEXT on inflammation in normotensive versus non-normotensive participants.

Purpose:
To assess whether there are differential changes in the inflammatory marker C-reactive protein (CRP) in normotensive versus non-normotensive participants in response to AEXT.

METHODS:
27 participants ages 41-71 were assessed. To be considered for inclusion participants had to be free of any cardiovascular disease, non-smoking and sedentary. After inclusion participants underwent blood draws, blood pressure (BP) measurements and aerobic exercise testing. Aerobic fitness was by measuring VO2max. Participants then underwent AEXT (3 days/week, 65% of VO2max, 40 minutes/day) for 6 months. Whole blood was sent to Quest Diagnostics for the measurement of serum levels of CRP.

Results:
CRP levels were not significantly different between normotensive (avg. BP=113/74 mmHg, N=13) and non-normotensive (avg. BP=131/82 mmHg, N=14) participants before (2.86 ± 0.82 vs. 3.65 ± 0.90 mg/L) or after (3.28 ± 1.00 vs. 2.75 ± 0.73 mg/L) AEXT. However, non-normotensive participants significantly (p≤0.016) lowered their CRP levels (3.65 ± 0.90 vs. 2.75 ± 0.73 mg/L), whereas the normotensive group did not. Neither group lowered their BP levels.

Conclusion:
AEXT is a proven tool for the treatment and prevention of HTN and systemic inflammation. Although AEXT did not lower BP in our setting, results suggest that AEXT may be an important tool in lowering systemic inflammation in non-normotensives who are at greater risk for cardiovascular disease.
Abstract 450: Dopamine D2 receptors regulate Wnt signaling in the kidney.
Authors: Zhang Yanrong , Yang Yu , Cuevas Santiago , Asico Laureano D , Escano Crisanto , Jose Pedro A , Armando Ines
Published: July 2021

We have already reported that dopamine D2 receptors (D
2
R) are involved in the regulation of blood pressure and renal inflammation. In mice selective renal
Drd2
silencing by subcapsular infusion of D
2
R siRNA for 7 days does not affect blood pressure but results in increased expression of inflammatory factors in the renal cortex, glomerulosclerosis, tubular epithelial degeneration, tubular dilation and cast formation, as well as increased expression of pro-apoptotic caspase-1 (1.34±0.02 fold; qRT-PCR n=5/ group, P<0.05) and decreased expression of the anti-apoptotic factors, Bcl2a (0.71±0.02 fold; P<0.05) and survivin (0.57±0.02 fold; P<0.03) in the D
2
R siRNA infused kidneys compared to those infused with non-silencing siRNA (NS siRNA). We hypothesized that some of this alterations are mediated by the Wnt pathway that is involved in cell survival and the development of fibrosis in the kidney. The expression of Wnt 3 (4.8±0.1 fold; n=3; P<0.05), and Wnt 5 (1.5±0.03 fold; P<0.05) was increased in the infused kidney, as well as that of the downstream targets Dkk1 (Dickkopf 1 homolog; 1.7±0.05 fold; P<0.05), Wisp1 (WNT1 induced secreted protein 1, 2.3±0.05 fold; P<0.05), Sfrp2 (secreted frizzled-related protein 2;1.9±0.10 fold; P<0.05), Fn1 (fibronectin 1; 1.3±0.03 fold; P<0.05), and TGFβ (1.6±0.04 fold; P<0.05). Silencing of
Drd2
(siRNA, 30 nM, 72 h) in mouse renal proximal tubule cells (mPTCs) also increased significantly the expression of Wnt3, Wnt5, Wisp1, Dkk1, and Sfrp2. In contrast D
2
R stimulationin mPTCs (quinpirole, 1μM,24 h) decreased the expression of Wnt3, Wnt 5 and their targets. Our results indicate that D
2
R function is important in the regulation of the Wnt pathway and that the alterations in D
2
R function result in profound modifications in the pathway potentially leading to cell death and fibrosis and hypertension.
Abstract 451: Depletion of Macrophage Prevents Exacerbated Renal Injury and Hypertension Induced by Degeneration of Trpv1-positive Nerves in Rats Subjected to Renal Ischemic Reperfusion and Salt Load
Authors: Yu Shuang-Quan , Wang Donna H
Published: July 2021

High salt intake after recovery from renal ischemia-reperfusion (I/R) injury leads to hypertension and renal inflammation. This study tests the hypothesis that degeneration of transient receptor potential vanilloid type 1 (TRPV1)-positive nerves exacerbates salt-induced hypertension and renal inflammation after I/R via enhancing renal macrophage infiltration. Rats were fed a low sodium (0.4%) diet for 5 weeks after capsaicin pre-treatment (CAP, 100 mg/kg, s.c.) and renal I/R, followed by macrophage depletion with clodronate liposome (LC, 1.3 ml/kg/wk, i.v.) combined with a high sodium (4%) diet for 4 weeks. Western blot showed that CAP pretreatment further decreased renal TRPV1 levels after I/R (P<0.05), which was not affected by LC treatment. Macrophage infiltration in the renal cortex and medulla and renal proinflammatory cytokine (TNF-α and IL-1 β) levels were increased in I/R rats and further intensified in I/R+CAP rats (P<0.05), which were abolished by LC in both I/R and I/R+CAP groups. Mean arterial pressure (MAP) was elevated in I/R rats and further increased in I/R+CAP rats (P<0.05), which was prevented by LC in both I/R and I/R+CAP groups. Decreased creatinine clearance (Sham: 0.54±0.06, I/R: 0.28±0.02, I/R+CAP: 0.16±0.02, Sham+LC: 0.54±0.03, I/R+LC: 0.51±0.04, I/R+CAP+LC: 0.49±0.04 ml/min/100 gbwt, p<0.05) and increased levels of plasma urea, urinary 8-isoprostane, renal connective tissue growth factor (CTGF), and renal collage I and IV were observed in I/R rats and exacerbated in I/R+CAP rats (P<0.05), which were restored to normal levels by LC in both I/R and I/R+CAP groups. Thus, degeneration of TRPV1-positive nerves aggravates hypertension and renal inflammation and fibrosis induced by I/R and high salt intake, possibly via enhancing renal macrophage infiltration and function. These data suggest that activation of TRPV1 after renal injury conveys renal protection against inflammation and fibrosis via inhibiting macrophage infiltration.
Abstract 457: Blockade of Nuclear Factor Kappa B Reverses Renal Fibrosis in Npr1 Gene-Disrupted Mice
Authors: Das Subhankar , Periyasamy Ramu , Pandey Kailash N
Published: July 2021

Binding of atrial natriuretic peptide (ANP) to its guanylyl cyclase/natriuretic peptide receptor-A (GC-A/NPRA) exerts diverse physiological effects by lowering the blood pressure and blood volume. The objective of the present study was to determine the effect of blockade of nuclear factor-kappa B, inhibitory kappa B kinase, and inhibitory kappa B alpha (NF-κB, IKK, IκBα) in the kidneys of
Npr1
(coding for GC-A/NPRA) gene-disrupted mice. The disruption of
Npr1
greatly

stimulated the renal NF-κB binding activity by 6-fold (57.12 ± 3.35 vs 9.42 ± 0.92), IKK activity by 8-fold (56.05 ± 3.83 vs 6.85 ± 0.90), and IκBα phosphorylation by 11-fold (46.67 ± 1.32 vs 4.15 ±0.58), respectively, in the kidneys of null mutant (-/-; 0-copy) mice as compared with wild-type (+/+; 2-copy) mice. Interestingly, the expression levels of IκBα were reduced by 80% (5.35 ± 0.58 vs 31.64 ± 1.13) and pro-inflammatory cytokines and renal fibrosis were enhanced by 6- to 8-fold and 5-fold (32.58 ±2.06 vs 5.85 ± 0.91), respectively, in 0-copy mice than 2-copy mice. However, the treatment of 0-copy mice with NF-κB inhibitors, andrographolide, pyrrolidine dithiocarbamate, and etanercept showed a substantial reduction in renal fibrosis by 50% (14.09 ± 2.13, 18.01 ± 1.69, and 15.88 ± 0.70, respectively), attenuation of pro-inflammatory cytokines gene expression by 60-65%, IKK activity by 60% (25.37 ± 2.22, 22.67 ± 2.23, and 19.21 ± 2.50), and IkBα phosphorylation by 65-70% (19.68 ± 1.35, 24.67 ± 1.44, 16.62 ± 1.42), respectively. Our findings demonstrate that the disruption of
Npr1
activates NF-κB activity, expression of various pro-inflammatory cytokines, and renal fibrosis in 0-copy mice. However, the treatments with NF-kB inhibitors suppress NF-kB activity and pro-inflammatory cytokines and repairs the fibrosis in the kidneys of
Npr1
null mutant mice. The present results suggest that the blockade of NF-kB activity provides protective effects against the inflammatory and fibrotic responses in the kidney.
Abstract 464: Non-alcoholic Fatty Liver Disease Produced by Mas Deficiency in ApoE-KO Mice
Authors: Silva Analina R , Aguilar Edenil C , Alvarez-Leite Jacqueline I , Santos Séio H , Arantes Rosa M , Bader Michael , Alenina Natalia , Santos Robson A
Published: July 2021

The non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome and recent studies have shown the involvement of the renin-angiotensin system in this pathology. We have previously shown that Mas deficiency in ApoE-KO mice results in a marked increase in hepatic triglyceride and total lipids. However, the role of the Ang-(1-7)/Mas in the NAFLD is still not fully understood. The aim of this study was to evaluate the role of Mas in liver steatosis using a double knockout Mas/ApoE (DKO) mice. C57Bl6, Mas-/- (Mas), ApoE-/- (ApoE), and DKO mice were killed at 20 weeks of age. Mas deficiency in ApoE leads to reduced insulin sensitivity and serum leptin (WT = 2.27 ± 0.73 ng/mL, n =5; Mas = 0.96 ± 0.25 ng/mL, n = 6; ApoE = 0.64 ± 0.05 ng/mL, n = 3; DKO = 0.27 ± 0.05, n = 4). Furthemore, the DKO mice presented decrease hepatic expression of the insulin receptor (WT = 0.739 ± 0.083 AU, n = 6; Mas = 0.567 ± 0.115 AU, n = 6; ApoE = 0.702 ± 0.073 AU, n = 6; DKO = 0.321 ± 0.053 AU, n = 6). The oral glucose tolerance test did not differ between groups, as well as serum insulin levels. The liver levels of lipid peroxidation were increased in DKO (WT = 0.58 ± 0.04 μM/g of protein, n = 6; Mas = 0.74 ± 0.09 μM/g of protein, n = 6; ApoE = 0.56 ± 0.01 μM/g of protein, n = 6; DKO = 0.78 ± 0.08 μM/g of protein, n = 6). Consistent with this alteration, histological analysis showed degenerative changes of DKO hepatocytes associated with macro-and microvesicular steatosis, but with few inflammatory infiltrates. The mechanism involved in the development of hepatic steatosis was assessed by Western blotting using primary antibodies to PPAR-α, LXR, FoxO1 S256, glycogen phosphorylase (GP) and glucose 6-phosphatase (G6Pase). The DKO group showed lower levels of hepatic expression of PPAR-α and phosphorylated FoxO1. In addition, the Mas deficiency in ApoE animals significantly increased the expression of LXR. However, no changes were observed in the hepatic expression of GP and G6Pase. In conclusion, our data show that the Mas modulates the activity of key transcriptional factors in hepatic lipid homeostasis.
Abstract 467: The Role of Obesity and Aging in Cardiovascular Remodeling in Monosodium Glutamate Treated Rats
Authors: Burlá Adriana K , Fortes Zuleica B , Oigman Wille , Neves Mario F
Published: July 2021

The monosodium glutamate (MSG)-induced obese rat is a model associated with insulin resistance and dyslipidemia. The aim of this study was to evaluate the interaction of obesity and aging in cardiovascular remodeling. Male Wistar rats received subcutaneous injections of MSG (4.0g/kg) from the second to the sixth day after birth. The first sacrifice was done at week 16, when insulin resistance of the MSG group was established, and at week 30 we did the second sacrifice, obtaining four groups: control 16-week (CON-16); monosodium glutamate 16-week (MSG-16); control 30-week (CON-30); monosodium glutamate 30-week (MSG-30). Systolic blood pressure (BP) was measured weekly by tail-cuff plethysmography. The myocardium tissue was fixed and stained with Sirius red. The lumen diameter, media thickness and media cross-sectional area (CSA) of the intramyocardial arteries were measured. Cardiac collagen density was estimated with optical microscopy using the Image Pro Plus analysis system. The Lee index was significantly higher in MSG groups (30.43±0.34 and 31.2±0.2 vs 29.5±0.22 and 29.7±1.0 g/cm, p<0.001). The systolic BP was significantly increased in the MSG-30 group (135±2 mmHg, p<0.001) comparing to CON-16 (113±2 mmHg), CON-30 (115±1 mmHg) and MSG-16 (108±2 mmHg). The morphological analyses show similar diameter at the intramyocardial arteries but media thickness was significantly greater in MSG-30 rats (16.3±0.2 μm
2
, p < 0.01) when compared to CON-16(12.5±0.5 μm
2
) and CON-30(13.±0.4 μm
2
) groups. Vascular remodeling was evident in obese groups observing an adverse effect of aging when measuring media-to-lumen ratio: 30.2±2.0% (CON-16), 39.9±3.7% (MSG-16), 39.3±1.2% (CON-30), 51.2±1.3% (MSG-30) (MSG-30 vs MSG-16 and CON-30 p< 0.05; MSG-30 vs CON-16, p< 0.001). Media CSA was also increased in MSG groups compared to control group resulting in an elevated growth index suggesting a hypertrophic vascular remodeling in these animals. Myocardial collagen density was significantly greater in obese (4.0±0.5 and 5.1±0.5 %) than in control rats (2.1±1.3% and 2.6±0.6%, p<0.01). We concluded that in this experimental model, the presence of obesity promoted the increase of blood pressure and accelerated the adverse cardiovascular remodeling observed in aging.
Abstract 477: Chronic Baroreflex Activation Improves Baroreflex Control of Heart Rate In Obesity
Authors: Iliescu Radu , Tudorancea Ionut , Irwin Eric , Lohmeier Thomas
Published: July 2021

Impaired baroreflex control of heart rate (BRS) and attendant risk for cardiac arrhythmias are associated with sympathetically-mediated obesity hypertension. Since both global and renal-specific sympathoinhibition have sustained antihypertensive effects in obesity, we compared BRS in obese dogs subjected to 7 days of electrical baroreflex activation (BA) and, after recovery (REC), to bilateral surgical renal denervation (RDX). After control (C) measurements and 4 weeks of high fat diet, fat intake was reduced (RF) to maintain a body weight increase of ∼ 50%, which led to an increase in mean arterial pressure (MAP) from 100±2 to 117±3 mmHg and heart rate (HR) from 86±3 to 130±4 bpm. Obesity hypertension was associated with decreased sensitivity of 24h spontaneous BRS (determined by the sequence technique from daily beat-to-beat time series) and pulse interval (PI) variability (24h SD). While both BA and RDX abolished hypertension, only BA diminished tachycardia and normalized BRS, consequently improving HR variability. Short-term systolic blood pressure variability (5 min SD) also decreased with high fat feeding and was restored to control upon reduction of fat intake (RF) during established obesity hypertension, suggesting a vasoplegic effect of fat. These data suggest that in addition to the antihypertensive effects of sympathoinhibition, BA corrects cardiac baroreflex dysfunction in obesity hypertension, presumably by enhancing cardiac vagal activity. This in turn markedly improves depressed HR variability, a known risk factor for cardiac arrhythmic events.
Abstract 478: Is Ang II-mediated mTOR/S6K1 Activation in Proximal Tubule Cells mTORC2-dependent?
Authors: Nistala Ravi , Sinak Catherine , Aroor Annayya , Locher Bonnie , Sowers James R , Whaley-Connell Adam
Published: July 2021

Introduction:
Activation of the mTOR nutrient sensing pathway in early diabetes has been implicated in glomerulomegaly, hyperfiltration and hypertrophy of the nephrons. Recent studies show that excess/deletion of mTOR/raptor (mTORC1) in the podocytes results in diabetic changes. Interestingly, mTOR exists in another complex called mTORC2 (mTOR/rictor), which has been shown to phosphorylate Akt at S473 and is proposed to regulate cell motility and actin cytoskeleton. Recently, growth factors such as angiotensin II (Ang II) have been identified as activators of mTORC1 in cardiomyocytes, intestinal epithelial cells and embryonic cell. However, the precise mechanism of mTORC1 activation in the proximal tubule cells (PTC) is largely unknown. We
hypothesized
that Ang II activation of mTORC1 is dependent on mTORC2 activation.

Methods:
Mice were subjected to Ang II (200ng/kg/min) via osmotic minipump and whole kidney lysates analyzed for mTORC1 activation. In parallel, acute Ang II (10
-7
M, 10min) treatment of opossum PTCs stably expressing rat AT1
B
R was carried out on 24 hour starved cultures preceded by 1 hour pretreatment with various inhibitors.

Results:
Ang II activated mTORC1/S6 kinase in kidney lysates (1.5-fold) and cultured PTCs (3-5 fold) as evidenced by increased phosphorylation of T389-S6K1, S240/244-RPS6 and T36/45-4EBP1. Ang II also activated mTORC2 (2-fold) as evidenced by p-S473-Akt. Upstream, Ang II caused phosphorylation of EGF receptor and inhibition of EGFR activation resulted in 30% inhibition of Akt activation and partial inhibition of mTOR/S6 kinase. Inhibition of PKC also resulted in partial inhibition of mTOR/S6 activation but the magnitude (50%) was higher than inhibition of EGFR signaling. Rapamycin (10nM) inhibited mTORC1 activation and not mTORC2 but PP242 (ATP site inhibitor, 8nM) completely abolished both mTORC1 and mTORC2 activation.

Conclusion:
Ang II activation of mTOR/S6K follows a distinct pattern in PTC when compared to other cell types. Ang II induced activation of mTOR/S6 kinase is mediated by both PKC and EGFR activation. mTORC2 appears to play a central role in regulating Ang II induced activation of mTOR/S6 kinase.
Abstract 482: Amyloid-β Peptides Induce a Signal Transduction via Activation of the α1-Adrenoreceptor in Vsmc and Cardiomyocytes
Authors: Haase Nadine , Haase Hannelore , Herse Florian , Luft Friedrich C , Muller Dominik N , Wallukat Gerd , Dechend Ralf
Published: July 2021

Hypertension is associated with increased risk of Alzheimer disease (AD) that features Amyloid-β peptide (Aβ) deposition in brain (neuritic plaques) and in blood vessels (cerebral amyloid angiopathy). Recently, it was shown by others that Aβ peptides exert a chronotropic effect in neonatal cardiomyocytes, similar to α1-adrenoreceptor autoantibodies (α-AB) as we described earlier. We hypothesized that Aβ peptides elicit a signal transduction pathway in vascular cells, induced by activation of the α1-adrenoreceptor. Aβ peptides (10-35) and (25-35) induced a positive chorontropic effect in the cardiac contraction assay (CCA) after long term activation up to 4 hours (28.84±1.04 bpm and 28.96±1.08 bpm). The effect was attenuated by the α1-receptor blockers urapidil and prazosin (1.72±0.4 bpm and -0.76±1.16 bpm). β1, β2, AT1, or AT2 receptor blockers had no effect on the positive chronotropic effect of Aβ (10-35) and (25-35). Using confocal microscopy and phosphospecific immunoblotting we observed that both peptides induced ERK 1/2 phosphorylation in Chinese hamster ovary (CHO) cells, overexpressing the α1A adrenoreceptor (CHO-α1-AR), but not in wildtype CHO. pERK was also induced in vascular smooth muscle cells (VSMC) and cardiomyocytes. Both Aβ peptides induced an intracellular Ca2+ signal in VSMC. The positive chronotropic response to Aβ (25-35) in the CCA was blocked with a peptide corresponding to the 1st extracellular loop of the α1-AR, the identical epitope to which α1-AB binds. Our data show that Amyloid-β peptides induce a signal transduction cascade via the α1-adrenoreceptor in VSMC and cardiomyocytes. These data might help explain the newly discovered association between hypertension and Alzheimer disease. The role of Aβ peptides in vascular medicine deserves further study.
Abstract 490: Constrictor Mechanism of the Afferent Arteriole Initiated by Na/H Exchanger in the Nephron
Authors: Wang Hong , D'Ambrosio Martin A , Ren YiLin , Garvin Jeffrey L , Carretero Oscar A
Published: July 2021

The afferent arteriole (Af-Art) accounts for most of renal vasculature resistance, thus controlling glomerular filtration rate and renal function. Two mechanisms have been described in which the nephron helps control Af-Art resistance, namely tubuloglomerular feedback (TGF), and connecting tubule glomerular feedback (CTGF). TGF is a constrictor mechanism initiated at the macula densa by the Na/K/2Cl cotransporter (NKCC2), while CTGF is a dilator mechanism initiated at the connecting tubule by the epithelial Na channel (ENaC). However, when NKCC2 is blocked by furosemide, CTGF-induced Af-Art dilation is not evident, thus we hypothesize that there is a constrictor mechanism that is furosemide-insensitive and counters CTGF. To test this, we used
in vivo
micropuncture of single nephrons. Stop-flow pressure (P
SF
) was measured as an index of glomerular capillary pressure (which decreases when the Af-Art constricts). Two consecutive P
SF
curves were generated by raising nephron perfusion from 0 to 40 nL/min while adding drugs to the tubular perfusate. The decrease in P
SF
induced by increasing nephron perfusion was blocked by furosemide 10
-4
M (control: 7.9±0.2 mmHg, furosemide: 0.4±0.2 mmHg,
P
<0.001, n=6), but was partially restored when blocking CTGF with the ENaC inhibitor benzamil 10
-6
M (furosemide: 0.2±0.1 mmHg, furosemide+benzamil: 4.3±0.3 mmHg,
P
<0.001, n=6). A possible explanation for these observations is that TGF may be activated to some degree by Na/H exchanger (NHE)-mediated Na entry at the macula densa when NKCC2 is blocked. When we added the NHE blocker dimethylamiloride (DMA, 10
-4
M) in the presence of furosemide and benzamil, the decrease in PSF was significantly prevented (furosemide+benzamil: 4.6±0.3 mmHg, furosemide+benzamil+DMA: 1.1±0.2 mmHg,
P
<0.001, n=6). Therefore, we conclude that a constrictor mechanism of the Af-Art is initiated by NHE in the nephron and is observable when NKCC2-mediated TGF and ENaC-mediated CTGF have been blocked.
Abstract 493: Impact of Renal Vasoconstriction on the Relationship Between Blood Pressure and Renal Injury in Angiotensin II-induced Hypertensive Rats
Authors: Polichnowski Aaron J , Picken Maria , Long Jianrui , Williamson Geoffrey , Griffin Karen , Bidani Anil
Published: July 2021

Ang II is thought to play a prominent role in the development of hypertension-induced renal disease via BP dependent and independent pathways; however the quantitative relationships between BP and renal injury have not been rigorously examined in Ang II-induced hypertension. The major goals of the present study were to assess: 1) the relationship between BP and renal injury in rats with hypertension induced by Ang II vs. renal mass reduction (RMR) and 2) the pressure-flow relationships in conscious Ang II-infused rats. One group of male Sprague-Dawley rats (Charles River) were implanted with a BP radiotransmitter and 10 days later administered Ang II (n=12; 500 ng/kg/min via osmotic minipump) or subjected to 3/4 RMR via right uninephrectomy + infarction of ∼ 1/2 of the left kidney (RKI, n=5). BP was measured continuously and kidneys were perfused fixed at 6 weeks for the assessment of renal injury. In a separate experiment, MAP and RBF (Transonic) were measured in conscious chronically instrumented rats. After recovery from surgery (∼7 days), baseline MAP and RBF were assessed (∼4 hours @ 200 Hz) on 2 consecutive days. Subsequently, rats were administered Ang II (n=6; 500 ng/kg/min) or saline (n=7; sham) via osmotic minipump and MAP and RBF were again assessed every 2-3 days for 10 days. Despite a higher average systolic BP over 6 weeks in Ang II (174±3 mmHg) vs. RKI (165±6 mmHg) rats, glomerulosclerosis (GS) was higher (p<0.05) in RKI (15±7% out of 100 glomeruli) vs. Ang II (6±1% out of 100 glomeruli) rats. Moreover, the slope of the relationship between BP and %GS (Δ%GS/ΔmmHg) was greater in RKI vs. Ang II rats. Both MAP (98±2 vs. 99±3 mmHg) and RBF (8.1±1vs. 8.2±1 ml/min) were similar at baseline in Ang II and sham rats, respectively. MAP was elevated by day 3 (123±6 mmHg) and further increased to 157±5 mmHg by day 10 in Ang II rats. Conversely, RBF was decreased at day 3 (6.6±0.6 ml/min) and the vasoconstriction persisted over the experimental protocol as RBF further decreased to 5.6±0.7 ml/min at day 10 in Ang II rats. In conclusion, Ang II-induced hypertension is associated with a diminished susceptibility to renal injury as compared to rats with RMR likely due, in part, to the AngII-induced vasoconstriction, which reduces BP transmission to the renal microvasculature.
Abstract 503: Regulation of D5 Dopamine Receptor on Renalase Expression and Function in Rat Renal Proximal Tubule Cells
Authors: Wang Shaoxing , Jose Pedro , Zeng Chunyu
Published: July 2021

The dopaminergic and sympathetic systems interact to regulate blood pressure. Our previous studies show the regulation of dopamine receptor on α
1
-adrenergic receptor function. Due to the regulation of renalase on sympathetic tone, we hypothesize that dopamine receptor, especially D
1
-like receptor, might regulate renalase in kidney. The effect of D
1
-like receptor on renalase expression and function was checked in immortalized renal proximal tubule (RPT) cells from Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHRs). It resulted that D
1
-like receptor agonist, fenoldopam (10
-7
-10
-5
M), increased renalase protein expression and function in WKY RPT cells, in contrast, decreased it in SHR cells. These effects were blocked by D
1
-like receptor antagonist SCH 23390 (10
-6
M). Fenoldopam increased renalase mRNA level in WKY RPT cells, but not in SHR cells. Fenoldopam increased the degradation of renalase protein in both WKY and SHR cells. However, the degradation degree was higher in SHR cells than in WKY cells. The regulation of D
1
-like receptor on renalase was mainly via D
5
receptor, because inhibition of D
5
, not D
1
receptor, by antisense blocked inhibitory effect of D
1
-like receptor on renalase in WKY cells. Moreover, inhibition of PKC, by PKC inhibitor 19-31, blocked the effect of fenoldopam on renalase expression; stimulation of PKC, by PKC agonist (PMA), inhibited renalase expression and function, indicating that PKC is involved in the process. Consistent with the
in-vitro
study, renalase expression was lower in kidney from SHRs than in WKY rats. It indicated that D
1
-like receptor, via D
5
receptor, regulates renalase expression and function in RPT cells, aberrant regulation of D
5
receptor on renalase might be involved in the pathogenesis of hypertension.
Abstract 57: Histone Deacetylase Inhibition Attenuates Early Life Stress-Induced Endothelial Dysfunction
Authors: Ho Dao H , Pollock Jennifer S
Published: July 2021

Epidemiological studies show that early life stress (ELS) is linked to cardiovascular disease in adulthood. We used a model of maternal separation with early weaning (MSEW) to study the mechanisms of ELS-mediated adult vascular dysfunction in male C57BL/6J mice. MSEW litters were subjected to maternal separation 4h/day (postnatal day (PD) 2 to 5) and 8h/day (PD6 to 16), and weaned at PD17. Control (CON) litters were undisturbed until weaning at PD21. All subsequent experiments were performed in adult mice (12 weeks old). We hypothesized that MSEW increases vascular inflammation and endothelial dysfunction in male mice. Systolic blood pressure (tail-cuff) of MSEW mice was not different from CON mice (109.3 + 10.9 vs 116.7 + 20.8 mmHg, respectively). Circulating soluble intercellular adhesion molecule (CON: 333.5 + 19.4 vs MSEW: 406.2 + 23.1 ng/ml; p = 0.03) and macrophage colony stimulating factor (CON: 737.4 + 19.6 vs MSEW: 945.3 + 65.4 pg/ml; p = 0.01) were elevated by MSEW. Also, aortic adventitial macrophage infiltration was increased in mice exposed to MSEW (F4/80 immunostaining; CON: 2.8 + 2.3 vs MSEW: 7.0 + 2.2 cells/mm
2
; p = 0.05). We performed wire myography on thoracic aortae to determine vasorelaxation with cumulative concentration-response curve to acetylcholine (ACh; 1 X 10
-9
M to 3 X 10
-5
M) and sodium nitroprusside (SNP; 1 X 10
-10
M to 3 X 10
-5
M). MSEW induced blunted ACh-mediated vasorelaxation (MSEW: 67.6 + 5.8 vs CON: 89.9 + 2.7 % of phenylephrine constriction (% of PE), p = 0.01), while SNP-induced vasorelaxation was similar in CON and MSEW mice. We further hypothesized that MSEW-induced endothelial dysfunction is mediated via increased histone deacetylase (HDAC) expression. Real-time quantitative PCR revealed upregulation of HDAC 1, 6 and 9 in aortae of MSEW mice (1.28 + 0.12, 1.28 + 0.18 and 1.65 + 0.05 fold change from CON, respectively, p < 0.05). Pretreatment with trichostatin A (TSA), an HDAC inhibitor, normalized ACh-induced vasorelaxation in aortae of MSEW mice (MSEW: 67.6 + 5.8 vs MSEW + TSA: 88.44 + 3.2 % of PE, p = 0.02), while not affecting ACh-induced vasorelaxation in aortae from CON mice (CON: 89.9 + 2.7 vs CON + TSA: 90.3 + 4.5 % of PE). We conclude that ELS induces blood pressure-independent endothelial dysfunction through an HDAC-mediated pathway.
Abstract 58: Intratracheal Delivery of Autologous Bone Marrow-derived Cells Attenuate Muscularization and Inflammation in Lungs of Monocrotaline-induced Pulmonary Hypertension Model Rats.
Authors: Yamazao Yoriko , Ishida Akio , Yamazato Masanobu , Fujita Jiro , Ohya Yusuke
Published: July 2021

Background:
Vascular remodeling and inflammation contribute to the pathogenesis and/or development of pulmonary hypertension. Bone marrow-derived cells (BMCs) include mesenchymal stem cells and progenitor cells play critical role in tissue repair as well as anti-inflammatory effects. Aim of this study was to investigate the effect of intratracheal delivered BMCs on monocrotaline (MCT)-induced muscuralization and inflammation in rat lung.

METHODS:
BMCs were isolated and cultured for 3 weeks. Seven days following MCT (60 mg/kg) treatment, DiI labeled autologous BMCs were intratracheally delivered to male Sprague-Dawley rats. Twenty-eight days following the MCT treatment, rats had hemodynamic studies. Hearts and lungs were removed to evaluate right ventricular (RV) hypertrophy and lung pathologies.

Results:
MCT treated rats had increased RV systolic pressure (RVSP), RV weight as well as wall thickness of small pulmonary arteries and alveolar septum thickness than those of placebo-treated control rats (all p values <0.01). Intratracheal delivery of autologous BMCs (1x106) 7 days after MCT prevented the increase in RVSP at 4 weeks compared with MCT alone (45.1 ± 2.23 versus 35.0 ± 3.84 mmHg, respectively; p<0.05). Furthermore, the intratracheal delivery of BMCs significantly attenuated the pulmonary vessel wall thickness (54.4 % ± 2.25 versus 17.8 % ± 2.69, p<0.01), and alveolar septum thickening (155.1 % ± 1.56 versus 114.2 % ± 1.16, p<0.01) accompanied with decreased numbers of inflammatory cells in perivascular areas and expression of proinflammatory cytokines compared with MCT alone. Immunohistochemical studies showed monocyte-like shaped DiI positive cells distributed in alveolar areas in BMCs delivered lungs, and some of those DiI positive cells expressed CD 68 and alpha smooth muscle cell actin.

Conclusion:
Intratracheal delivery of autologous BMCs prevented MCT-induced pulmonary hypertension by attenuation of vascular muscularization and inflammation in rat lung.