Short- and long-term enalapril affect renal medullary hemodynamics in the spontaneously hypertensive rat

1999 ◽  
Vol 276 (1) ◽  
pp. R10-R16 ◽  
Author(s):  
Stephen A. W. Dukacz ◽  
Michael A. Adams ◽  
Robert L. Kline
Keyword(s):  
Blood Flow ◽  
Arterial Pressure ◽  
Spontaneously Hypertensive Rat ◽  
Day Treatment ◽  
Ace Inhibition ◽  
Spontaneously Hypertensive ◽  
Short And Long Term ◽  
Pressure Natriuresis ◽  
The Relationship

Long-term angiotensin-converting enzyme (ACE) inhibition in the spontaneously hypertensive rat (SHR) resets pressure natriuresis and shifts the relationship between renal arterial pressure (RAP) and renal interstitial hydrostatic pressure (RIHP) to lower levels of arterial pressure. These effects persist after withdrawal of treatment. The purpose of this study was to determine the effect of short- and long-term ACE inhibition on medullary blood flow (MBF). Enalapril (25 mg ⋅ kg−1 ⋅ day−1in drinking water) was given to male SHR from 4 to 14 wk of age. Four weeks after stopping treatment, we measured MBF over a wide range of RAP using laser-Doppler flowmetry in anesthetized rats. Additional rats, either untreated or previously treated for 10 wk, received 3-day enalapril treatment just before the experiment. MAP (mmHg ± SE) was 178 ± 6 ( n = 8), 134 ± 6 ( n = 8), 138 ± 5 ( n = 9), and 111 ± 6 mmHg ( n = 9) for the untreated, 3 day, 10 wk, and 10 wk + 3 day groups, respectively. Total renal blood flow for the groups receiving 3-day treatment was significantly higher when compared with that in rats with an intact renin-angiotensin system. Three-day treatment had no effect on the relationship between RAP and RIHP, whereas that in rats receiving 10-wk treatment was shifted to lower levels of RAP by ∼30 mmHg. Both 10-wk and 3-day treatment independently increased the slope of the RAP versus MBF relationship at values of RAP > 100 mmHg. The slopes in perfusion units/mmHg were 0.12 ± 0.01 ( n = 8), 0.26 ± 0.01 ( n = 8), 0.27 ± 0.01 ( n = 9), and 0.30 ± 0.02 ( n = 9) for the untreated, 3 day, 10 wk, and 10 wk + 3 day groups, respectively. These results indicate that the effect of short-term and the persistent effect of long-term enalapril alter renal medullary hemodynamics in a way that may contribute to the resetting of the pressure-natriuresis relationship in treated rats.

Selective effect of tempol on renal medullary hemodynamics in spontaneously hypertensive rats

2001 ◽  
Vol 281 (5) ◽  
pp. R1420-R1425 ◽  
Author(s):  
Ming-Guo Feng ◽  
Stephen A. W. Dukacz ◽  
Robert L. Kline
Keyword(s):  
Blood Flow ◽  
Angiotensin Ii ◽  
Arterial Pressure ◽  
Spontaneously Hypertensive Rats ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive ◽  
Long Term Treatment ◽  
Wide Range ◽  
Short And Long Term

The present study assessed the short- and long-term effect of tempol, a membrane-permeable mimetic of superoxide dismutase, on renal medullary hemodynamics in spontaneously hypertensive rats (SHR). Tempol was given in the drinking water (1 mM) for 4 days or 7 wk (4–11 wk of age), and medullary blood flow (MBF) was measured over a wide range of renal arterial pressure by means of laser-Doppler flowmetry in anesthetized rats. In addition, the response of the medullary circulation to angiotensin II (5–50 ng · kg−1 · min−1 iv) was determined in SHR treated for 4 days with tempol. Compared with control SHR, short- and long-term treatment with tempol decreased arterial pressure by ∼20 mmHg and increased MBF by 35–50% without altering total renal blood flow (RBF) or autoregulation of RBF. Angiotensin II decreased RBF and MBF dose dependently (∼30% at the highest dose) in control SHR. In SHR treated with tempol, angiotensin II decreased RBF (∼30% at the highest dose) but did not alter MBF significantly. These data indicate that the antihypertensive effect of short- and long-term administration of tempol in SHR is associated with a selective increase in MBF. Tempol also reduced the sensitivity of MBF to angiotensin II. Taken together, these data support the idea that tempol enhances vasodilator mechanisms of the medullary circulation, possibly by interacting with the nitric oxide system. Increased MBF and reduced sensitivity of MBF to angiotensin II may contribute to the antihypertensive action of tempol in SHR.

The persistent effect of long-term enalapril on pressure natriuresis in spontaneously hypertensive rats

1997 ◽  
Vol 273 (1) ◽  
pp. F104-F112 ◽  
Author(s):  
S. A. Dukacz ◽  
M. A. Adams ◽  
R. L. Kline
Keyword(s):  
Arterial Pressure ◽  
Spontaneously Hypertensive Rats ◽  
Day Treatment ◽  
Renin Angiotensin System ◽  
Hypertensive Rats ◽  
Angiotensin System ◽  
Spontaneously Hypertensive ◽  
Persistent Effect ◽  
Pressure Natriuresis

Long-term angiotensin-converting enzyme inhibitor treatment has been shown to have a persistent antihypertensive effect in spontaneously hypertensive rats (SHR) long after discontinuation of treatment. To test the hypothesis that this persistent effect involves a shift in the pressure-natriuresis relation, we performed experiments in male, anesthetized SHR at 18 wk of age with fixed neural and hormonal influences on the kidney. Renal function was assessed at various levels of arterial pressure using standard clearance techniques. Enalapril (25 mg.kg-1.day-1 in drinking water) was administered from 4 to 14 wk of age and again 3 days before renal function studies. The following four groups of SHR were studied: 1) 10-wk treatment, 2) 10-wk + 3-day treatment, 3) 3-day treatment, and 4) untreated. Groups 1 and 4 had an intact renin-angiotensin system; groups 2 and 3 had the renin-angiotensin system blocked. Mean arterial pressure (MAP, mmHg; means +/- SE) under Inactin anesthesia was 139 +/- 4 (n = 9), 109 +/- 3 (n = 8), 149 +/- 1 (n = 9), and 181 +/- 7 mmHg (n = 9) for each of the four groups, respectively. Glomerular filtration rate was similar in all groups at resting levels of MAP, whereas renal blood flow was elevated in all treatment groups when compared with that in untreated SHR. Pressure-natriuresis, pressure-diuresis, and pressure-fractional sodium excretion curves for the 10-wk treatment group and 3-day only treatment group were shifted leftward to significantly lower pressures by approximately 25 mmHg, compared with the untreated group. The curves for the treated +3-day group were shifted an additional 30 mmHg to the left. The relationship between renal artery pressure (RAP) and renal interstitial hydrostatic pressure was also shifted 25-30 mmHg but only in rats that received the long-term treatment with enalapril. Three-day enalapril had no significant effect on this relationship. These data indicate that the persistent effect of long-term enalapril treatment on arterial pressure in SHR is the result of a shift in the pressure-natriuresis relationship. The mechanism for this effect involves hemodynamic changes that act to improve transmission of RAP to the interstitium, resulting in enhanced sodium excretion for a given level of RAP.

Genetic co-segregation of renal haemodynamics and blood pressure in the spontaneously hypertensive rat

1988 ◽  
Vol 74 (1) ◽  
pp. 63-69 ◽  
Author(s):  
S. B. Harrap ◽  
A. E. Doyle
Keyword(s):  
Blood Flow ◽  
Glomerular Filtration Rate ◽  
Mean Arterial Pressure ◽  
Arterial Pressure ◽  
Glomerular Filtration ◽  
Renal Blood Flow ◽  
Filtration Rate ◽  
Spontaneously Hypertensive Rat ◽  
Plasma Renin ◽  
Spontaneously Hypertensive

1. To determine the relevance of renal circulatory abnormalities found in the immature spontaneously hypertensive rat (SHR) to the genetic hypertensive process, glomerular filtration rate and renal blood flow were measured in conscious F2 rats, derived from crossbreeding SHR and normotensive Wistar–Kyoto rats (WKY), at 4, 11 and 16 weeks of age by determining the renal clearances of 51Cr-ethylenediaminetetra-acetate and 125I-hippuran respectively. Plasma renin activity was measured at 11 and 16 weeks of age. 2. Mean arterial pressure, glomerular filtration rate and renal blood flow increased between 4 and 11 weeks of age. Between 11 and 16 weeks the mean glomerular filtration rate and renal blood flow did not alter, although the mean arterial pressure rose significantly. At 11 weeks of age, during the developmental phase of hypertension, a significant negative correlation between mean arterial pressure and both glomerular filtration rate and renal blood flow was noted. However, by 16 weeks when the manifestations of genetic hypertension were more fully expressed, no correlation between mean arterial pressure and renal blood flow or glomerular filtration rate was observed. Plasma renin activity was negatively correlated with both glomerular filtration rate and renal blood flow, but the relationship was stronger at 11 than at 16 weeks of age. 3. These results suggest that the reduction in renal blood flow and glomerular filtration rate, found in immature SHR, is genetically linked to the hypertension and may be of primary pathogenetic importance. It is proposed that the increased renal vascular resistance in these young animals stimulates the rise of systemic arterial pressure which returns renal blood flow and glomerular filtration rate to normal.

Restoration of vasa recta hemodynamics and pressure natriuresis in SHR by L-arginine

1995 ◽  
Vol 268 (5) ◽  
pp. F907-F912 ◽  
Author(s):  
T. S. Larson ◽  
J. C. Lockhart
Keyword(s):  
Blood Flow ◽  
Perfusion Pressure ◽  
Spontaneously Hypertensive Rat ◽  
Urinary Sodium Excretion ◽  
Renal Perfusion ◽  
Spontaneously Hypertensive ◽  
Medullary Blood Flow ◽  
Vasa Recta ◽  
Wistar Kyoto ◽  
Pressure Natriuresis

An increase in medullary blood flow has been implicated as a mediator of the natriuresis following increases in renal perfusion pressure (RPP). We examined whether administration of L-arginine, the substrate for nitric oxide production, restores the impaired vasa recta hemodynamic response to increases in RPP and the blunted pressure natriuresis of the spontaneously hypertensive rat (SHR). The response of descending (QDVR) and ascending vasa recta blood flow (QAVR) and of urinary sodium excretion (UNaV) was examined as RPP was increased by means of an adjustable aortic clamp placed above the renal arteries in young SHR and Wistar-Kyoto (WKY) rats. When RPP was increased in SHR receiving infusion of L-arginine (n = 7), QDVR and QAVR increased significantly in association with increases in UNaV. In SHR receiving the inactive enantiomer, D-arginine (n = 7), similar increases in RPP failed to increase QAVR and QDVR and were associated with an attenuated increase in UNaV. WKY animals infused with either D-arginine or L-arginine had increases in QDVR, QAVR, and UNaV in response to increases in RPP that were of similar magnitude to SHR receiving L-arginine. Thus the administration of L-arginine to SHR restores the pressure-dependent increases in renal medullary hemodynamics in association with restoration of pressure natriuresis.

QUALITY OF LIFE PROBLEMS OF GYNECOLOGICAL CANCER PATIENTS

2017 ◽  
Vol 63 (3) ◽  
pp. 368-374
Author(s):  
Olga Churuksaeva ◽  
Larisa Kolomiets
Keyword(s):  
Quality Of Life ◽  
Gynecological Cancer ◽  
Social Aspects ◽  
Cancer Data ◽  
Life Problems ◽  
Anticancer Treatment ◽  
Short And Long Term ◽  
The Relationship

Due to improvements in short- and long-term clinical outcomes a study of quality of life is one of the most promising trends in oncology today. This review analyzes the published literature on problems dealing with quality of life of patients with gynecological cancer. Data on quality of life with respect to the extent of anticancer treatment as well as psychological and social aspects are presented. The relationship between quality of life and survival has been estimated.

The Relationship Between Brain Fog and Medication Adherence for Individuals With Hypothyroidism

2021 ◽  
pp. 105477382110381
Author(s):  
Kelly Haskard-Zolnierek ◽  
Courtney Wilson ◽  
Julia Pruin ◽  
Rebecca Deason ◽  
Krista Howard
Keyword(s):  
Memory Impairment ◽  
Hormone Replacement ◽  
Long Term Memory ◽  
Adherence Level ◽  
Thyroid Hormone Replacement ◽  
Memory Impairments ◽  
Cognitive Failures ◽  
Short And Long Term ◽  
The Relationship

Individuals with hypothyroidism suffer from symptoms including impairments to cognition (i.e., “brain fog”). Medication can help reduce symptoms of hypothyroidism; however, brain fog may hinder adherence. The aim of this study was to determine if memory impairment and cognitive failures are related to treatment nonadherence in 441 individuals with hypothyroidism. Participants with a diagnosis of hypothyroidism and currently prescribed a thyroid hormone replacement medication were placed in two groups according to adherence level and compared on validated scales assessing impairments to memory and cognition. Results indicated a significant association between treatment nonadherence and self-reported brain fog, represented by greater cognitive and memory impairments. Nonadherent individuals indicated impairments with prospective, retrospective, and short- and long-term memory; and more cognitive failures, compared to adherent individuals. Findings suggest the importance of interventions to enhance adherence for individuals with brain fog, such as encouraging the use of reminders.

ISSUES OF THE RELATIONSHIP BETWEEN THE STATE BUDGET AND ECONOMIC GROWTH IN UZBEKISTAN

2021 ◽  
Vol 4 (7) ◽  
pp. 4-19
Author(s):  
Akmal Baltayevich Allakuliev ◽  
Keyword(s):  
Economic Growth ◽  
The State ◽  
Rate Of Return ◽  
State Budget ◽  
Macroeconomic Shocks ◽  
Dynamic Correlations ◽  
Short And Long Term ◽  
The Impact ◽  
The Relationship

The article examines the interaction of the country's GDP with the state budget in the short and long term, the impact of the macro-fiscal mechanism on the country's economic growth on the example of Uzbekistan.The aim of the study is to identify dynamic correlations between the country's state budget expenditures and the economic growth of the macro-fiscal mechanism in the short and long term, as well as to analyze the approximation or rate of return of GDP and the state budget to equilibrium during various macroeconomic shocks. and hesitation.The scientific novelties of the research are:

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