Functional evidence for renorenal reflexes in the rat

1980 ◽  
Vol 239 (3) ◽  
pp. F265-F270 ◽  
Author(s):  
R. E. Colindres ◽  
W. S. Spielman ◽  
N. G. Moss ◽  
W. W. Harrington ◽  
C. W. Gottschalk
Keyword(s):  
Filtration Rate ◽  
Renal Denervation ◽  
Left Kidney ◽  
Mean Value ◽  
Urinary Volume ◽  
Hemodynamic Changes ◽  
Nerve Activity ◽  
Functional Changes ◽  
Simultaneous Decrease ◽  
The Right

Acute left renal denervation in anesthetized volume-expanded rats produced an ipsilateral diuresis and natriuresis in 19 animals. A simultaneous decrease of glomerular filtration rate, p-aminohippurate clearance, urinary volume (P < 0.002), and percentage of filtered sodium excreted (4.0 +/- 0.6 (SE) vs. 1.9 +/- 0.4%, P < 0.003) occurred in the right innervated kidney in 10 rats. Prior denervation of the right kidney in the other nine rats prevented the renal hemodynamic changes and the fall of urinary volume and of sodium excretion (3.9 +/- 0.6 vs. 4.3 +/- 0.5%) by the right kidney after left renal denervation. Nerve traffic to the right kidney was measured in six other animals after left renal denervation and was found to increase to a mean value 33.8 +/- 6.3% above control levels (P < 0.007) 0-30 min after denervation, with a further significant increase to 66.2 +/- 16.1% above control levels (P < 0.025) 30-60 min after denervation. These results indicate that the functional changes in the right kidney after contralateral renal denervation in volume-expanded rats are caused by a reflex increase in nerve traffic to the right kidney, possibly as a consequence of an interruption of afferent nerve activity originating in the left kidney.

STUDY OF RADIATION CHARACTERISTICS THE RENAL FUNCTION IN PATIENTS WITH TYPE 2 DIABETES

2014 ◽  
pp. 73-77
Author(s):  
Van Chuong Nguyen ◽  
Thi Kim Anh Nguyen
Keyword(s):  
Type 2 Diabetes ◽  
Renal Function ◽  
Glomerular Filtration Rate ◽  
Glomerular Filtration ◽  
Filtration Rate ◽  
Disease Duration ◽  
Left Kidney ◽  
Cross Sectional ◽  
The Right

Background: A Research glomerular filtration rate (GFR) of 61 patients with type 2 diabetes mellitus with renal scanning 99mTc-DTPA glomerular filtration rate at the hospital 175. Objective: (1) To study characteristics of imaging of renal function. (2) Understanding the relationship between GFR with blood sugar, HbA1c, blood pressure and albuminuria in patients with type 2 diabetes. Methods: Descriptive, prospective, cross-sectional study. Clinical examination, Clinical tests and 99mTc-DTPA GFR gamma - camera renography for patients. Result: GFR of the study group was 75,4 ± 22,3 ml/phut/1,73m2, the left kidney was 35,0 ± 13,0 is lower than the right kidney and 39,8 ± 11,9; p <0,01. There is no correlation between GFR with blood glucose and HbA1c, the risk of reduced GFR in hypertensive group associated is OR = 6,5 with p<0,01; albuminuria (+) is OR = 4,2 with p <0,01; and disease duration > 10 years is OR = 3,5 with p <0.01. Conclusion: GFR of the left kidneys is lower than the right kidney; correlation decreased GFR associated with hypertension, albuminuria and disease duration. Keywords: GFR, diabetes, albuminuria

scholarly journals Acute renal denervation normalizes aortic function and decreases blood pressure in spontaneously hypertensive rats

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Nathalia Juocys Dias Moreira ◽  
Fernando dos Santos ◽  
Edson Dias Moreira ◽  
Daniela Farah ◽  
Leandro Eziquiel de Souza ◽  
...  
Keyword(s):  
Spontaneously Hypertensive Rats ◽  
Renal Denervation ◽  
Vascular Reactivity ◽  
Urinary Volume ◽  
Hypertensive Rats ◽  
Response Curves ◽  
Spontaneously Hypertensive ◽  
Functional Changes ◽  
Sham Surgery ◽  
Acute Responses

AbstractMechanisms involved in the acute responses to renal denervation (RDN) have yet to be fully understood. We assessed urinary volume, autonomic control and aorta vascular reactivity after acute RDN. Male normotensive Wistar rats and spontaneously hypertensive rats (SHR) were divided into normotensive + RDN (ND) or sham surgery (NS), and hypertensive + RDN (HD) or sham surgery (HS). Metabolic parameters and hemodynamic measurements were recorded 72h and 4 days after intervention, respectively. Aortic rings were studied 7 days post RDN in an isometric myograph. Concentration–response curves to phenylephrine, sodium nitroprusside and acetylcholine (10–10–10−5 M) were performed. Two-way ANOVA was used for group comparisons and differences reported when p < 0.05. Results are presented as mean ± SEM. Urinary volume was 112% higher in HD vs. HS (HS = 14.94 ± 2.5 mL; HD = 31.69 ± 2.2 mL) and remained unchanged in normotensive rats. Systolic BP was lower in HD rats (HS = 201 ± 12 vs. HD = 172 ± 3 mmHg) without changes in normotensive group. HD group showed increased HF and LF modulation (HS = 5.8 ± 0.7 ms2vs. HD = 13.4 ± 1.4 ms2; HS = 3.5 ± 0.7 ms2vs. HD = 10.5 ± 1.7 ms2, respectively). RDN normalized vascular reactivity in HD rats and increased phenylephrine response in ND rats. Acute fall in BP induced by RDN is associated with increased urinary volume, which in turn may also have contributed to functional changes of the aorta.

Effect of renal denervation, furosemide, and acute saline loading on postobstructive diuresis in the rat

1981 ◽  
Vol 59 (1) ◽  
pp. 59-64 ◽  
Author(s):  
D. R. Wilson ◽  
U. Honrath
Keyword(s):  
Filtration Rate ◽  
Renal Denervation ◽  
Nerve Activity ◽  
Renal Nerve ◽  
Sodium Potassium ◽  
Water Excretion ◽  
Saline Loading ◽  
Anaesthetized Rats ◽  
Renal Nerve Activity ◽  
Solute Excretion

The effect of acute or chronic renal denervation, furosemide, or acute saline loading on the postobstructive diuresis (POD) which occurs after relief of 24-h bilateral ureteral obstruction (BUO) was studied in anaesthetized rats. Acute renal denervation during POD 1–2 h after relief of BUO had no effect on glomerular filtration rate or sodium, potassium, water, or solute excretion, in contrast with its natriuretic and diuretic effect in sham-operated rats. Intravenous furosemide or acute saline loading caused a further marked increase in sodium and water excretion during POD, demonstrating the ability of the kidney undergoing POD to respond to other types of natriuretic stimuli. Chronic renal denervation prior to BUO had no effect on subsequent POD.The lack of response of the BUO kidney undergoing POD to acute denervation contrasts with the changes in renal function following denervation of the unilateral postobstructive kidney. The results indicate that the kidney undergoing POD after relief of BUO may be functionally denervated and suggest that inhibition of renal nerve activity could contribute to the pathophysiology of POD.

Evidence for a peritubular-to-luminal flux phosphate in the dog kidney

1977 ◽  
Vol 232 (2) ◽  
pp. F159-F166
Author(s):  
E. G. Schneider ◽  
L. A. McLane
Keyword(s):  
Glomerular Filtration Rate ◽  
Renal Artery ◽  
Filtration Rate ◽  
Left Kidney ◽  
Proximal Tubules ◽  
Tubular Lumen ◽  
Dog Kidney ◽  
Phosphate Loading ◽  
The Mean ◽  
The Right

The possible presence of a direct influx of phosphate into the tubular lumen of the dog kidney was examined by two different techniques. A 0.3-ml bolus of 32PO4 and [3H]inulin was injected into the renal artery of dogs with and without phosphate loading. The mean urinary transit time (TT) for PO4 was consistently less than the TT for inulin in nonphosphate-loaded dogs. Following phosphate loading the TT for phosphate approached but did not equal the TT for inulin. In contrast, after microinjections of 32PO4 and [3H]inulin into proximal tubules, the urinary TT of PO4 was significantly longer than the TT of inulin. The application of 32PO4 and [3H]inulin to the surface of the left kidney was associated with a greater recovery of 32PO4 from the left kidney compared to that from the right kidney. The recovery of [3H]inulin was proportional to the glomerular filtration rate for both kidneys. Application of the 32PO4 and [3H]inulin to the surface of a muscle resulted in an equal recovery of phosphate and inulin from both kidneys. The results demonstrate the presence of a detectable tubular influx of phosphate.

scholarly journals Microdissection of the Human Renal Nervous System

Hypertension ◽  
2020 ◽  
Vol 76 (4) ◽  
pp. 1240-1246 ◽  
Author(s):  
Arturo García-Touchard ◽  
Eva Maranillo ◽  
Blanca Mompeo ◽  
José Ramón Sañudo
Keyword(s):  
Nervous System ◽  
Renal Artery ◽  
Renal Denervation ◽  
Left Kidney ◽  
Renal Nerves ◽  
Renal Nerve ◽  
Main Renal Artery ◽  
Area Under Roc Curve ◽  
Human Cadavers ◽  
The Right

Despite the use of renal denervation to treat hypertension, the anatomy of the renal nervous system remains poorly understood. We performed a detailed quantitative analysis of the human renal nervous system anatomy with the goal of optimizing renal denervation procedural safety and efficacy. Sixty kidneys from 30 human cadavers were systematically microdissected to quantify anatomic variations in renal nerve patterns. Contrary to current clinical perception, not all renal innervation followed the main renal artery. A significant portion of the renal nerves (late arriving nerves) frequently reached the kidney (73% of the right kidney and 53% of the left kidney) bypassing the main renal artery. The ratio of the main renal artery length/aorta-renal hilar distance proved to be a useful variable to identify the presence/absence of these late arriving nerves (odds ratio, 0.001 (95% CI, 0.00002–0.0692; P : 0.001) with a cutoff of 0.75 (sensitivity: 0.68, specificity: 0.83, area under ROC curve at threshold: 0.76). When present, polar arteries were also highly associated with the presence of late arriving nerve. Finally, the perivascular space around the proximal main renal artery was frequently occupied by fused ganglia from the solar plexus (right kidney: 53%, left kidney: 83%) and/or by the lumbar sympathetic chain (right kidney: 63%, left kidney: 60%). Both carried innervation to the kidneys but importantly also to other abdominal and pelvic organs, which can be accidentally denervated if the proximal renal artery is targeted for ablation. These novel anatomic insights may help guide future procedural treatment recommendations to increase the likelihood of safely reaching and destroying targeted nerves during renal denervation procedures.

Selective efferent chemical sympathectomy of rat kidneys

1985 ◽  
Vol 249 (4) ◽  
pp. R496-R501
Author(s):  
L. M. LeNoble ◽  
R. W. Lappe ◽  
M. J. Brody ◽  
H. A. Struyker Boudier ◽  
J. F. Smits
Keyword(s):  
Blood Pressure ◽  
Renal Denervation ◽  
Left Kidney ◽  
Posterior Hypothalamus ◽  
Renal Nerves ◽  
Chemical Sympathectomy ◽  
Arterial Blood ◽  
6 Hydroxydopamine ◽  
The Right ◽  
And Control

Surgical denervation of kidneys results in interruption of both afferent and efferent renal nerves. We attempted selective efferent renal denervation in rats by slow infusions of 6-hydroxydopamine (6-OHDA) into the right renal artery. Integrity of efferent renal nerves was assessed by chemical and physiological methods and by measuring responses of mean arterial blood pressure (MAP) and heart rate (HR) to intrarenal (ir) infusion of bradykinin in conscious rats. Results were compared with those in surgically denervated and ir saline-infused rats. Surgical denervation of left kidney reduced renal norepinephrine (NE) to 58 and 14% of control levels at 1 and 7 days, respectively, after surgery. Increase in left renal resistance during posterior hypothalamus (PH) stimulation was only 70 +/- 28% (n = 5) compared with 289 +/- 69% (n = 6) in control animals. Response in opposite kidney was unchanged. Although 0.1 mg 6-OHDA ir caused considerable reduction of NE levels in both kidneys, responses to PH stimulation were unchanged. 6-OHDA (1 mg) reduced NE levels in infused and control kidney and atria. Functional evidence for denervation was only obtained in the kidney infused with 6-OHDA. Responses of MAP and HR to ir bradykinin were unchanged 7 days after 1 mg 6-OHDA. The data suggest that ir 6-OHDA results in functional efferent sympathectomy without affecting afferent renal nerves.

Perimeter of The Tricuspid Valve: A Cadaveric Human Heart Study

2020 ◽  
Vol 11 (3) ◽  
pp. 3424-3428
Author(s):  
Kirti Chaudhary ◽  
Amey Dhatrak ◽  
Brij Raj Singh ◽  
Ujwal Gajbe
Keyword(s):  
Tricuspid Valve ◽  
Tricuspid Regurgitation ◽  
Right Ventricular Dysfunction ◽  
Mean Value ◽  
Female Population ◽  
Functional Tricuspid Regurgitation ◽  
Lv Dysfunction ◽  
Heart Study ◽  
Males And Females ◽  
The Right

Historically, the research on the right ventricle (RV) has been neglected by his left equivalent because of the complexity of left ventricle (LV) dysfunction. Tricuspid regurgitation (TR) can be classified as linked to primary valve disease or functional in nature, but most are functional. Although it was historically assumed that such functional Tricuspid regurgitation, i.e. arising from leftsided disease, and it can be resolved after corrective surgery, but after successful surgery, on the aortic or mitral valve annular dilatation, the Tricuspid regurgitation and right ventricular dysfunction may persist.To study the circumference of tricuspid orifice and it’s the diameter in two perpendicular planes and its comparison among the male and female population. The material for the present study comprised of 50 formalin fixed human hearts (35 males and 15 females) which were obtained from the department of anatomy. In this study, it is observed that: The mean value of circumference of a tricuspid orifice is 11.01+/-0.63 cm. The diameter of tricuspid orifice along the frontal dimension is 3.06+/-0.38 cm, and the diameter along the sagittal dimension is 2.26+/-0.23 cm. The measurements of the circumference of tricuspid orifice reported for males and females in western countries were higher than the present study and the diameter along the frontal dimension is greater than the diameter along the sagittal dimension. The tricuspid valve diameter along the frontal dimension was more than the diameter along the sagittal dimension in both males and females.

scholarly journals Right Heart Structure, Geometry and Function Assessed by Echocardiography in 6-Year-Old Children Born Extremely Preterm—A Population-Based Cohort Study

2020 ◽  
Vol 10 (1) ◽  
pp. 122
Author(s):  
Lilly-Ann Mohlkert ◽  
Jenny Hallberg ◽  
Olof Broberg ◽  
Gunnar Sjöberg ◽  
Annika Rydberg ◽  
...  
Keyword(s):  
Preterm Birth ◽  
Ductus Arteriosus ◽  
Population Based ◽  
Right Heart ◽  
Functional Changes ◽  
Cardiac Phenotype ◽  
Extremely Preterm ◽  
Healthy Control ◽  
The Right ◽  
And Function

Preterm birth has been associated with altered cardiac phenotype in adults. Our aim was to test the hypothesis that children surviving extremely preterm birth have important structural or functional changes of the right heart or pulmonary circulation. We also examined relations between birth size, gestational age, neonatal diagnoses of bronchopulmonary dysplasia (BPD) and patent ductus arteriosus (PDA) with cardiac outcomes. We assessed a population-based cohort of children born in Sweden before 27 weeks of gestation with echocardiography at 6.5 years of age (n = 176). Each preterm child was matched to a healthy control child born at term. Children born preterm had significantly smaller right atria, right ventricles with smaller widths, higher relative wall thickness and higher estimated pulmonary vascular resistance (PVR) than controls. In preterm children, PVR and right ventricular myocardial performance index (RVmpi’) were significantly higher in those with a PDA as neonates than in those without PDA, but no such associations were found with BPD. In conclusion, children born extremely preterm exhibit higher estimated PVR, altered right heart structure and function compared with children born at term.

Improvement in prefrontal thalamic connectivity during the early course of the illness in recent-onset psychosis: a 12-month longitudinal follow-up resting-state fMRI study

2020 ◽  
pp. 1-9
Author(s):  
Daniel Bergé ◽  
Tyler A. Lesh ◽  
Jason Smucny ◽  
Cameron S. Carter
Keyword(s):  
Resting State ◽  
Resting State Fmri ◽  
Functional Changes ◽  
Recent Onset ◽  
Fmri Study ◽  
Clinical Meaning ◽  
Mixed Pattern ◽  
The Right ◽  
Over Time

Abstract Background Previous research in resting-state functional magnetic resonance imaging (rs-fMRI) has shown a mixed pattern of disrupted thalamocortical connectivity in psychosis. The clinical meaning of these findings and their stability over time remains unclear. We aimed to study thalamocortical connectivity longitudinally over a 1-year period in participants with recent-onset psychosis. Methods To this purpose, 129 individuals with recent-onset psychosis and 87 controls were clinically evaluated and scanned using rs-fMRI. Among them, 43 patients and 40 controls were re-scanned and re-evaluated 12 months later. Functional connectivity between the thalamus and the rest of the brain was calculated using a seed to voxel approach, and then compared between groups and correlated with clinical features cross-sectionally and longitudinally. Results At baseline, participants with recent-onset psychosis showed increased connectivity (compared to controls) between the thalamus and somatosensory and temporal regions (k = 653, T = 5.712), as well as decreased connectivity between the thalamus and left cerebellum and right prefrontal cortex (PFC; k = 201, T = −4.700). Longitudinal analyses revealed increased connectivity over time in recent-onset psychosis (relative to controls) in the right middle frontal gyrus. Conclusions Our results support the concept of abnormal thalamic connectivity as a core feature in psychosis. In agreement with a non-degenerative model of illness in which functional changes occur early in development and do not deteriorate over time, no evidence of progressive deterioration of connectivity during early psychosis was observed. Indeed, regionally increased connectivity between thalamus and PFC was observed.

scholarly journals 1003 A Case of Tunnel-Vision in Upper Renal Tract Imaging: The Invisible Gorilla

2021 ◽  
Vol 108 (Supplement_2) ◽  
Author(s):  
M Swamad ◽  
M K Quraishi ◽  
S Ahmed
Keyword(s):  
Renal Mass ◽  
Left Kidney ◽  
Interesting Case ◽  
Ct Scans ◽  
Renal Ultrasound ◽  
Ultrasound Scan ◽  
Surgical Team ◽  
Tunnel Vision ◽  
Impact Patient Care ◽  
The Right

Abstract We present an interesting case of a 70-year-old female who presented with haematuria on the suspected cancer pathway. Renal ultrasound showed a vascular renal mass on her right kidney measuring 8x7cm with an unremarkable left kidney. She underwent a laparoscopic radical nephrectomy following confirmation of an 8cm renal mass in the right kidney on the contrasted staging CT scan with a repeat review at the multidisciplinary meeting. Post-operatively a subsequent review of the pre-operative CT and ultrasound scan, showed an incidental large left(contralateral) upper quadrant retroperitoneal fatty mass sized 15x10cm, displacing the stomach and spleen. Further investigation in the form of an MRI Abdomen excluded features of a liposarcoma, resulting in the diagnosis of a large retroperitoneal lipoma. This case highlights the significance of selective attention in imaging interpretation. We believe this to be a prime example of the level of meticulousness required as fat-rich tissues have low attenuation on CT-scans, which can be easily missed out. A cautious multi-clinician interpretation of scans should be performed to avoid missing potentially sinister pathology which would impact patient care dramatically. This case has led to more thorough review of future pre-operative imaging by the operating surgical team.

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