We investigated the signaling basis for tubule pathology during fibrosis after renal injury. Numerous pathways are activated physiologically to direct regeneration acute kidney injury (AKI) but several persist pathologically repair. Among these, transforming growth factor (TGF)-β is particularly important because it controls epithelial differentiation and profibrotic cytokine production. found that increased TGF-β AKI accompanied by PTEN loss from proximal tubules (PT). With time,...

Preexisting CKD may affect the severity of and/or recovery from AKI. We assessed impact prior graded normotensive renal mass reduction on ischemia-reperfusion–induced Rats underwent 40 minutes ischemia 2 weeks after right uninephrectomy and surgical excision both poles left kidney (75% mass), (50% or sham mass. The AKI was comparable among groups, which reflected by similarly increased serum creatinine (SCr; approximately 4.5 mg/dl) at days, tubule necrosis 3 vimentin-expressing regenerating...

Renal injury in the Dahl salt-sensitive rat mimics human forms of hypertension that are particularly prevalent black individuals, but mechanisms lead to development this incompletely understood. We studied impact renal perfusion pressure (RPP) on model. During salt-induced over 2 wk, RPP left kidney was maintained at control levels (125 +/- mmHg) by continuous servocontrol inflation an aortic balloon implanted between arteries; during same period, right rose 164 8 mmHg. After wk a 4% salt...

To understand the role of muscle perfusion in sex differences fatigue, we compared time to task failure, postcontraction (active) hyperemia, and vascular conductance for an isometric fatiguing contraction performed by young men women with handgrip muscles at 20% maximal voluntary (MVC) force. In study 1, (n = 16) were stronger than 18), 2, 7) matched strength. Isometric contractions sustained during two sessions: 1) until target force could no longer be achieved or 2) 4 min. For both...

Unilateral ischemia-reperfusion (UIR) injury leads to progressive renal atrophy and tubulointerstitial fibrosis (TIF) is commonly used investigate the pathogenesis of acute kidney injury-chronic disease transition. Although it well known that contralateral nephrectomy (CNX), even 2 wk post-UIR injury, can improve recovery, physiological mechanisms tubular signaling pathways mediating such improved recovery remain poorly defined. Here, we examined hemodynamic associated with UIR its reversal...

Studies were designed to determine the effects of increases renal perfusion pressure on production hydrogen peroxide (H 2 O ) and NO − +NO 3 within outer medulla. Sprague-Dawley rats studied with either capsule intact or removed ascertain contribution changes medullary blood flow interstitial hydrostatic H production. Responses three 30-minute step (from ≈85 ≈115 ≈145 mm Hg) using adjustable aortic occluders proximal distal left artery. Medullary determined by microdialysis increased at each...

The purpose of this study was to compare the effects high-load (H-load) periodized resistance training and high-repetition (H-rep) reverse step loading on endurance performance. Twenty-six female university rowers (age = 20 +/- 1 year) were randomly assigned H-load (5 novice, 8 varsity) or H-rep (7 6 groups. Subjects pre- posttested using a 2,000-m rowing ergometer test. Outcome variables included VO2 peak, time test completion, total power, average power per stroke, number strokes, stroke...

The susceptibility to renal perfusion pressure (RPP)–induced injury was investigated in angiotensin II (Ang II)– versus norepinephrine (NE)-infused hypertensive rats. To determine the magnitude of RPP-induced injury, Sprague-Dawley rats fed a 4% salt diet were instrumented with servocontrolled aortic balloon occluder positioned between arteries maintain RPP left kidney at baseline levels whereas right exposed elevated during 2-week infusion Ang IV (25 ng/kg per minute), NE (0.5, 1.0, and 2.0...

Renal oxidative stress is thought to contribute both the etiology and associated renal injury in angiotensin (Ang) II–dependent hypertension. The contribution of Ang II versus elevated perfusion pressure (RPP) on albuminuria this model hypertension was explored present study by chronically servocontrolling RPP left kidney comparing responses with right uncontrolled sham rats. Hypertension produced Sprague-Dawley rats fed a 4% NaCl diet chronic IV infusion (25 ng/kg per minute)....

The N(ω)-nitro-l-arginine methyl ester (l-NAME) model is widely employed to investigate the role of nitric oxide (NO) in renal injury. present studies show that Sprague-Dawley rats from Harlan (H) and Charles River (CR) exhibit strikingly large differences susceptibility l-NAME nephropathy. After 4 wk (∼50 mg·kg(-1)·day(-1) drinking water), H (n = 13) exhibited expected hypertension [average radiotelemetric systolic blood pressure (BP), 180 ± 3 mmHg], proteinuria (136 17 mg/24 h), glomerular...

Chronic ANG II infusion in rodents is widely used as an experimental model of hypertension, yet very limited data are available describing the resulting blood pressure-renal flow (BP-RBF) relationships conscious rats. Accordingly, male Sprague-Dawley rats ( n = 19) were instrumented for chronic measurements BP (radiotelemetry) and RBF (Transonic Systems, Ithaca, NY). One week later, two or three separate 2-h recordings obtained at 24-h intervals, addition to recordings. Rats then...

The balance between angiotensin II (ANG II) and nitric oxide plays an important role in renal function is thought to contribute the progression of injury experimental hypertension. In present study, we investigated extent blood pressure (BP)-dependent BP-independent pathways following 2 wk hypertension produced by intravenous infusion ANG (5 ng·kg⁻¹·min⁻¹)+N(ω)-nitro-l-arginine methyl ester (l-NAME; 1.4 μg·kg⁻¹·min⁻¹) male Sprague-Dawley rats. An aortic balloon occluder was positioned...

Acute kidney injury (AKI) is a major complication in hospitalized patients and associated with elevated mortality rates. Numerous recent studies indicate that AKI also significantly increases the risk of chronic disease (CKD), end-stage renal (ESRD), hypertension, cardiovascular disease, those who survive AKI. Moreover, ESRD after substantially higher preexisting CKD. However, underlying mechanisms by which CKD interact to promote remain poorly understood. The recently developed models...

Abstract Sodium bicarbonate (NaHCO3) is commonly utilized as a therapeutic to treat metabolic acidosis in people with chronic kidney disease (CKD). While increased dietary sodium chloride (NaCl) known promote volume retention and increase blood pressure, the effects of NaHCO3 loading on pressure CKD remain unclear. In present study, we compared NaCl retention, injury both 2/3 5/6 nephrectomy remnant rats, well-established rodent model CKD. We tested hypothesis that promotes greater increases...

The relative contribution of self-perpetuating versus hemodynamic-induced fibrosis to the progression chronic kidney disease (CKD) after acute injury (AKI) is unclear. In present study, male Sprague-Dawley rats underwent right uninephrectomy and were instrumented with a blood pressure radiotelemeter. Two weeks later, separate groups subjected 40 minutes renal ischemia-reperfusion or sham surgery followed up for 4 16 determine extent which glomerulosclerosis tubulointerstitial as result...

Most patients with essential hypertension do not exhibit substantial renal damage. Renal autoregulation by preventing glomerular transmission of systemic pressures has been postulated to mediate this resistance. Conversely, malignant nephrosclerosis (MN) develop when severe exceeds a critical ceiling. If the concept is valid, even modest blood pressure (BP) reductions below threshold regardless antihypertensive class (1) should prevent MN and (2) lead healing already developed lesions. Both...

Sodium bicarbonate (NaHCO3) slows the decline in kidney function patients with chronic disease (CKD), yet mechanisms mediating this effect remain unclear. The Dahl salt-sensitive (SS) rat develops hypertension and progressive renal injury when fed a high salt diet; however, of alkali loading on has never been investigated model. We hypothesized that NaHCO3 protects from development rats via luminal alkalization which limits formation tubular casts, are prominent pathological feature To...

ANG II is thought to increase the susceptibility hypertension-induced renal disease (HIRD) via blood pressure (BP)-dependent and BP-independent pathways; however, quantitative relationships between BP HIRD have not been examined in II-infused hypertensive rats. We compared relationship radiotelemetrically measured Sprague-Dawley rats (Harlan) chronically administered (300–500 ng·kg −1 ·min , n = 19) for 4 wk versus another commonly employed pharmacological model of hypertension induced by...

Background Abnormal renal hemodynamic responses to salt‐loading are thought contribute salt‐sensitive (SS) hypertension. However, this is based largely on studies in anesthetized animals, and little data available conscious SS salt‐resistant rats. Methods Results We assessed arterial blood pressure, function, flow during administration of a 0.4% NaCl high‐salt (4.0% NaCl) diet conscious, chronically instrumented 10‐ 14‐week‐old Dahl consomic rats which chromosome 1 from the Brown‐Norway...

The diet-induced obesity (DIO) model is frequently used to examine the pathogenesis of obesity-related pathologies; however, only minimal glomerulosclerosis (GS) has been reported after 3 mo. We investigated if GS develops over longer periods DIO and examined potential role hemodynamic mechanisms in its pathogenesis. Eight-week-old male obesity-prone (OP) obesity-resistant (OR) rats (Charles River) were administered a moderately high-fat diet for 5 Radiotelemetrically measured blood...

Significance Statement Real-time dynamics of renal autoregulation to stabilize blood flow and GFR protect glomeruli from hypertension in conscious animals with spontaneously fluctuating BP remain uncharacterized. Using novel methods analyze relationships between flow, the authors show that rats display autoregulatory restoration <10 seconds; is significantly slower impaired autoregulation, resulting exposure increased glomerular pressure. However, unlike under anesthesia, achieve complete...

Ebben, W.P., A.G. Kindler, K.A. Chirdon, N.C. Jenkins, A.J. Polichnowski, and A.V. Ng. The effect of high-load vs. high-repetition training on endurance performance. J. Strength Cond. Res. 18(3):513–517. 2004.—The purpose this study was to compare the effects (H-load) periodized resistance (H-rep) reverse step loading Twenty-six female university rowers (age = 20 ± 1 year) were randomly assigned H-load (5 novice, 8 varsity) or H-rep (7 6 groups. Subjects pre- posttested using a 2,000-m...

Noninvasive determination of the severity parenchymal injury in acute kidney remains challenging. Edema is an early pathological process following injury, which may correlate with changes volume. The goal present study was to test hypothesis that “increases volume measured vivo using ultrasound degree renal injury.” Ischemia-reperfusion (IR) varying length used produce graded tissue injury. We first determined 1) whether regional rats varied (0, 15, 30, and 45 min) warm bilateral IR 2) this...

Impairments in insulin sensitivity can occur patients with chronic kidney disease (CKD). Correction of metabolic acidosis has been associated improved CKD, suggesting that may directly promote resistance. Despite this, the effect acid or alkali loading on a rodent model CKD (remnant kidney) not investigated. Such studies could better define relationship between blood pH and sensitivity. We hypothesized remnant rats, would loss homeostasis consequently decrease To test this hypothesis, we...