Naloxone attenuates development of hypertension in two-kidney one-clip Goldblatt rats

1988 ◽  
Vol 255 (6) ◽  
pp. E839-E842
Author(s):  
M. Chen ◽  
J. G. Lee ◽  
R. L. Malvin ◽  
B. S. Huang

The present experiments were designed to determine if an opiate antagonist affects blood pressure in two-kidney one-clip Goldblatt rats. Male Sprague-Dawley rats were divided into three groups. Group 1 received an infusion of saline intraperitoneally via an osmotic pump and left renal artery constriction (RAC). In group 2, rats were treated the same as group 1, except that they received an intraperitoneal infusion of naloxone (100 micrograms/h). Group 3 received the same infusion of naloxone without RAC. Naloxone-infused Goldblatt rats showed a significantly lower systolic blood pressure (SBP) than saline-infused Goldblatt rats (132 +/- 7 vs. 160 +/- 9 mmHg at day 14), but a higher SBP than control (132 +/- 7 vs. 106 +/- 1 mmHg). Infusion of naloxone did not significantly change SBP in normotensive rats. Renal renin activity in the clipped kidney was higher than in the nonclipped kidney in groups 1 and 2. Plasma renin activity (PRA) in both groups of Goldblatt rats was higher than in group 3, but no significant difference was found between the two groups of Goldblatt rats (groups 1 and 2). Naloxone (1.5 microM) did not affect the basal secretion of renin by isolated cortical slices from untreated rats. The present data demonstrate that naloxone significantly attenuates the development of hypertension in two-kidney one-clip rats. The attenuation of blood pressure was not associated with the changes in PRA, renal renin activity, or plasma aldosterone concentrations. The data support the hypothesis that the endogenous opioid system may be involved in the development of renovascular hypertension.

2018 ◽  
Vol 315 (5) ◽  
pp. F1478-F1483 ◽  
Author(s):  
Mohammad Saleem ◽  
Xitao Wang ◽  
Indira Pokkunuri ◽  
Mohammad Asghar

We tested a hypothesis that superoxide, by inducing Sp3, increases renal renin activity, renal angiotensin II type 1 receptor (AT1R) function, and blood pressure (BP) in rats. Group 1 rats were treated with vehicle, saline. Group 2 rats were treated with superoxide dismutase (SOD) inhibitor diethylthiocarbamate (DETC). Group 3 rats were treated with DETC and an SOD mimetic, tempol. Group 4 rats were treated with tempol only. All four groups of rats were treated for 2 wk then anesthetized, and BP was recorded. Thereafter, diuresis and natriuresis in response to AT1R blocker candesartan were determined. When compared with vehicle rats, BP increased in DETC rats. The increased BP in DETC rats decreased with tempol. Diuresis and natriuresis in response to candesartan increased in controls, and this further increased in DETC rats and decreased with tempol. A second set of four groups of rats underwent the same treatment as above and were anesthetized, and their kidneys were obtained for biochemical studies. The levels of superoxide but not hydrogen peroxide increased, whereas SOD activities decreased further in the renal cortical tissues of DETC rats than vehicle rats. These effects were attenuated with tempol in DETC rats. Moreover, tissue renin activity and abundance of membranous AT1R proteins increased more in DETC rats than vehicle rats, and decreased with tempol in DETC rats. Furthermore, the levels of lysine-acetylated, but not serine-phosphorylated, Sp3 increased more in the nuclei of DETC rats than vehicle rats. The increased levels of Sp3 lysine acetylation decreased in DETC rats with tempol. Taken together, our results suggest that superoxide activates renal Sp3 via lysine acetylation increasing renin activity, AT1R function, and BP in rats.


1979 ◽  
Vol 236 (5) ◽  
pp. H665-H671
Author(s):  
J. M. Rojo-Ortega ◽  
F. P. Queiroz ◽  
J. Genest

Malignant hypertension was induced in Sprague-Dawley rats by a complete aortic ligation above the left renal artery. The effects of saline (0.9% NaCl) administration on the development and course of the malignant hypertensive vascular disease were studied and the treated rats were compared to non-saline-treated animals and to sham-operated controls in the early and chronic phases of the disease. In the early phase, blood pressure, hematocrit, body weight, and hypertensive vascular disease were characteristic of the malignant hypertensive process and were without significant difference in saline- and non-saline-treated animals. In contrast, the sham-operated rats remained normotensive and did not present abnormal histological findings. Plasma renin activity although decreased in the hypertensive saline-treated animals was not suppressed. In the chronic phase, NaCl administration caused an average increase of 40 g body weight during the 1-wk period this solution was given, but did not result in any improvement in blood pressure levels and vascular disease in treated rats compared to non-saline-treated animals.


VASA ◽  
2020 ◽  
Vol 49 (4) ◽  
pp. 281-284
Author(s):  
Atıf Yolgosteren ◽  
Gencehan Kumtepe ◽  
Melda Payaslioglu ◽  
Cuneyt Ozakin

Summary. Background: Prosthetic vascular graft infection (PVGI) is a complication with high mortality. Cyanoacrylate (CA) is an adhesive which has been used in a number of surgical procedures. In this in-vivo study, we aimed to evaluate the relationship between PVGI and CA. Materials and methods: Thirty-two rats were equally divided into four groups. Pouch was formed on back of rats until deep fascia. In group 1, vascular graft with polyethyleneterephthalate (PET) was placed into pouch. In group 2, MRSA strain with a density of 1 ml 0.5 MacFarland was injected into pouch. In group 3, 1 cm 2 vascular graft with PET piece was placed into pouch and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. In group 4, 1 cm 2 vascular graft with PET piece impregnated with N-butyl cyanoacrylate-based adhesive was placed and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. All rats were scarified in 96th hour, culture samples were taken where intervention was performed and were evaluated microbiologically. Bacteria reproducing in each group were numerically evaluated based on colony-forming unit (CFU/ml) and compared by taking their average. Results: MRSA reproduction of 0 CFU/ml in group 1, of 1410 CFU/ml in group 2, of 180 200 CFU/ml in group 3 and of 625 300 CFU/ml in group 4 was present. A statistically significant difference was present between group 1 and group 4 (p < 0.01), between group 2 and group 4 (p < 0.01), between group 3 and group 4 (p < 0.05). In terms of reproduction, no statistically significant difference was found in group 1, group 2, group 3 in themselves. Conclusions: We observed that the rate of infection increased in the cyanoacyrylate group where cyanoacrylate was used. We think that surgeon should be more careful in using CA in vascular surgery.


1984 ◽  
Vol 52 (03) ◽  
pp. 253-255 ◽  
Author(s):  
C Isles ◽  
G D O Lowe ◽  
B M Rankin ◽  
C D Forbes ◽  
N Lucie ◽  
...  

SummaryWe have previously shown abnormalities of haemostasis suggestive of intravascular coagulation in patients with malignant hypertension, a condition associated with retinopathy and renal fibrin deposition. To determine whether such abnormalities are specific to malignant hypertension, we have measured several haemostatic and haemorheological variables in 18 patients with malignant hypertension (Group 1), 18 matched healthy controls (Group 2), and 18 patients with non-malignant hypertension (Group 3) matched for renal pathology, blood pressure and serum creatinine with Group 1. Both Groups 1 and 3 had increased mean levels of fibrinogen, factor VIIIc, beta-thrombo- globulin, plasma viscosity and blood viscosity (corrected for haematocrit); and decreased mean levels of haematocrit, antithrombin III and platelet count. Mean levels of fast antiplasmin and alpha2-macroglobulin were elevated in Group 1 but not in Group 3. We conclude that most blood abnormalities are not specific to malignant hypertension; are also present in patients with non-malignant hypertension who have similar levels of blood pressure and renal damage; and might result from renal damage as well as promoting further renal damage by enhancing fibrin deposition. However increased levels of fibrinolytic inhibitors in malignant hypertension merit further investigation in relation to removal of renal fibrin.


To identify the prevalence of early pathology of cardiovascular diseases, a survey of 400 200 girls) in the age group 15 and 17 years old was conducted as a part of routine medical of the level of blood pressure (BP) was carried out, with the calculation of the average level pressure on the basis of three separate measurements estimated by percentile tables for a registration of a standard resting ECG in 12 leads. According to the results of the survey, into 3 groups: with an increase in blood pressure above 95 ‰ (group 1 – 16 people), which recorded in males (p<0,05); Group 2 (67 people) – adolescents with a normal blood pressure level and group 3 of adolescents with a decrease in blood pressure below 5 ‰ changes in the form of rhythm and conduction disturbances were noted in almost every a predominance of sinus tachycardia in the first group. In the third group of adolescents, form of ectopic rhythm and pacemaker migration were significantly more frequently only 78 % of adolescents were referred for consultation and in-depth examination by a pediatric cardiologist.


2021 ◽  
Vol 28 (3) ◽  
pp. 328-338
Author(s):  
Ogbutor Udoji Godsday ◽  
Nwangwa Eze Kingsley ◽  
Nwogueze Bartholomew Chukwuebuka ◽  
Chukwuemeka Ephraim ◽  
Ezunu Emmanuel ◽  
...  

Decline in normal physiological pulmonary function has been attributed to premorbid conditions such as prehypertension. Research evidence suggests that physical activity reduces age-related decline in pulmonary function and improves the efficiency of the lungs in prehypertensive patients. However, there is a scarcity of data evidence relating to isometric exercise and pulmonary function. Furthermore, the interrelationship between the intensity and duration of isometric exercise and pulmonary function in these patients is still uncertain. Therefore, this study was undertaken to investigate the effect of isometric handgrip exercise on pulmonary function capacity in adults with prehypertension. To determine the effectiveness of isometric handgrip exercise on pulmonary function capacity in adults with prehypertension. A quasi experiment using a pre- and post-exercise method was carried out in two out-patients hospital settings. The sample comprised 192 sedentary pre-hypertensive subjects, aged between 30–50 years, that were randomly distributed into three groups of 64 participants each. The subjects performed, for 24 consecutive days, an isometric handgrip exercise at 30% Maximum Voluntary Contraction (M.V.C.). At the end of the 24 days, group one (GP1) discontinued, while group two (GP2) continued the exercise protocol for another 24 consecutive days and group three (GP3) continued with the exercise protocol for another 24 consecutive days but at 50% M.V.C. Determinants of lung function (outcomes) were Forced Expiratory Volume in 1 s (FEV1), Forced Vital Capacity (FVC), FEV1/FVC Ratio and Peak Expiratory Flow Rate (PEFR). The study shows that there was no statistically significant difference in the pre- and post-exercise outcomes for FEV1, FVC, FEV1/FVC Ratio and PEFR after 24 days for group 1. In group 2, there was a statistically significant difference in the FVC [(mean = 0.12 ± 0.12), (p = 0.002)], FEV1 [(mean = 0.15 ± 0.17), (p = 0.003)] and PEF [(mean = 0.85 ± 0.35), (p = 0.001)] after 48 days. In group 3, there was a statistically significant difference (p = 0.001) in all the outcomes assessed after 48 days. There was a between groups difference in favour of group 2 compared with group 1 for outcomes of FEV1 [(mean = 0.142 ± 0.68), (p = 0.005)] and PEF [(mean = 0.83 ± 0.19), (p = 0.0031)]. There was statistically significant difference in favour of group 3 compared to group 2, by increasing the exercise intensity from 30% to 50% M.V.C., for outcomes of FVC [mean change = 0.10 ± 0.052), (p = 0.005)], FEV1/FVC [mean change = 3.18 ± 0.75), (p = 0.017)] and PEF [(mean change = 0.86 ± 0.35), (p = 0.001)] after 48 days. Isometric handgrip exercise (after 48 days at 30% to 50% M.V.C.) improves outcomes of pulmonary function capacity in adults with prehypertension. Meanwhile, duration and/or increase in intensity of the isometric effort significantly contributed to the affects attained.


Arthroplasty ◽  
2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Zhijie Chen ◽  
Kaizhe Chen ◽  
Yufei Yan ◽  
Jianmin Feng ◽  
Yi Wang ◽  
...  

Abstract Objective To evaluate the effect of medial posterior tibial slope (PTS) on mid-term postoperative range of motion (ROM) and functional improvement of the knee after medial unicompartmental knee arthroplasty (UKA). Methods Medical records of 113 patients who had undergone 124 medial UKAs between April 2009 through April 2014 were reviewed retrospectively. The mean follow-up lasted 7.6 years (range, 6.2–11.2 years). Collected were demographic data, including gender, age, height, weight of the patients. Anteroposterior (AP) and lateral knee radiographs of the operated knees were available in all patients. The knee function was evaluated during office follow-up or hospital stay. Meanwhile, postoperative PTS, ROM, maximal knee flexion and Hospital for Special Surgery (HSS) knee score (pre−/postoperative) of the operated side were measured and assessed. According to the size of the PTS, patients were divided into 3 groups: group 1 (<4°), group 2 (4° ~ 7°) and group 3 (>7°). The association between PTS and the knee function was investigated. Results In our cohort, the average PTS was 2.7° ± 0.6° in group 1, 5.6° ± 0.9° in group 2 and 8.7° ± 1.2° in group 3. Pairwise comparisons showed significant differences among them (p < 0.01). The average maximal flexion range of postoperative knees in each group was 112.4° ± 5.6°, 116.4° ± 7.2°, and 117.5° ± 6.1°, respectively, with significant difference found between group 1 and group 2 (p < 0.05), and between group 1 and group 3 (p < 0.05). However, the gender, age, and body mass index (BMI) did not differ between three groups and there was no significant difference between groups in terms of pre−/postoperative HSS scores or postoperative knee ROM. Conclusion A mid-term follow-up showed that an appropriate PTS (4° ~ 7°) can help improve the postoperative flexion of knee. On the other hand, too small a PTS could lead to limited postoperative knee flexion. Therefore, the PTS less than 4° should be avoided during medial UKA.


2021 ◽  
pp. 1-7
Author(s):  
Emre Erdem ◽  
Ahmet Karatas ◽  
Tevfik Ecder

<b><i>Introduction:</i></b> The effect of high serum ferritin levels on long-term mortality in hemodialysis patients is unknown. The relationship between serum ferritin levels and 5-year all-cause mortality in hemodialysis patients was investigated in this study. <b><i>Methods:</i></b> A total of 173 prevalent hemodialysis patients were included in this study. The patients were followed for up to 5 years and divided into 3 groups according to time-averaged serum ferritin levels (group 1: serum ferritin &#x3c;800 ng/mL, group 2: serum ferritin 800–1,500 ng/mL, and group 3: serum ferritin &#x3e;1,500 ng/mL). Along with the serum ferritin levels, other clinical and laboratory variables that may affect mortality were also included in the Cox proportional-hazards regression analysis. <b><i>Results:</i></b> Eighty-one (47%) patients died during the 5-year follow-up period. The median follow-up time was 38 (17.5–60) months. The 5-year survival rates of groups 1, 2, and 3 were 44, 64, and 27%, respectively. In group 3, the survival was lower than in groups 1 and 2 (log-rank test, <i>p</i> = 0.002). In group 1, the mortality was significantly lower than in group 3 (HR [95% CI]: 0.16 [0.05–0.49]; <i>p</i> = 0.001). In group 2, the mortality was also lower than in group 3 (HR [95% CI]: 0.32 [0.12–0.88]; <i>p</i> = 0.026). No significant difference in mortality between groups 1 and 2 was found (HR [95% CI]: 0.49 [0.23–1.04]; <i>p</i> = 0.063). <b><i>Conclusion:</i></b> Time-averaged serum ferritin levels &#x3e;1,500 ng/mL in hemodialysis patients are associated with an increased 5-year all-cause mortality risk.


2019 ◽  
Vol 71 (1) ◽  
Author(s):  
Mohamed MesbahTahaHassanin ◽  
Ahmad ShafieAmmar ◽  
Radwa M. Abdullah ◽  
Mohammad Hassan Khedr

Abstract Background Right ventricular apical pacing with the resultant left ventricular dyssynchrony often leads to depressed systolic function and heart failure. This study aimed at investigating the relation between various septal locations guided by ECG and fluoroscopy and the intermediate term functional capacity of the patients. Results Fifty patients who received a single lead pacemaker with assumed > 90% pacemaker dependency. Patients were randomized according to RV pacing site RV into group 1 “high septum” (n = 15), group 2 “mid septum” (n = 25), and group 3 “low septum” (n = 10) using QRS vector and duration as well as fluoroscopic parameters. Their clinical status was assessed 6 months after device implementation using 6-min walk test (6MWT). The study showed that paced QRS complex duration itself has no significant difference between the different septal pacing locations (P-value 0.675), although its combination with the paced QRS complex vector can signify the optimal pacing site and 6MWT showed a significant difference among the groups in favor of group 1; group 1 (413.3 ± 148.5), group 2 (359.8 ± 124.6), and group 3 (276.0 ± 98.5) P value 0.04. Conclusion There was a significant difference found between the three septal pacing sites concerning the patient functional capacity with superiority of high septal location. By contrast, different septal sites showed no significant difference of the paced QRS complex duration. To optimize the pacing site in the septum, assessment of the paced QRS vector in leads I and III is of a great benefit especially when combined with paced QRS complex duration assessment.


Hypertension ◽  
2017 ◽  
Vol 70 (suppl_1) ◽  
Author(s):  
Ayuna Yamaoka ◽  
Yukiko Segawa ◽  
Saki Maruyama ◽  
Natsumi Saito ◽  
Hiroko Hashimoto ◽  
...  

Objective: Hesperidin (HES) is a flavonoid which is contained in citrus fruit peel. It has physiological effects on blood vessels such as strengthening capillary vessels. Thus, it is known to be one of the effective ingredients of herbal medicine. Some studies have shown that the intake of HES decreases blood pressure (BP) in spontaneously hypertensive rats. The antihypertensive effect of HES is suggested to be due to vasodilation by nitric oxide (NO). However, its mechanism has not been clarified in detail. In this study, we observed whether HES intake decreases BP in 2-kidney, 1-clip renovasucular hypertensive rats (2K1C) and evaluated endothelial NO synthase (eNOS) mRNA to investigate its role in the mechanism. Methods: Male Sprague-Dawley rats (6 weeks old) were treated with sham operation (SHAM) or clipping the left renal artery (2K1C). After surgery, the rats started receiving continuously a control diet (C) or a diet containing 0.1% (w/w) HES for 6 weeks. The systolic BP (SBP) was measured by a tail-cuff method every week. At the end of the protocol, mean arterial blood pressure (MAP) was measured in each rat under anesthesia. Then, the aortas were removed for extracting mRNA. eNOS mRNA expression was evaluated using real-time RT-PCR. Results: At the end of the protocol, SBP in 2K1C-C was significantly higher than in SHAM-C (170±6 vs 117±6 mmHg, p <0.001). On the other hand, 2K1C-HES was lower in SBP (141±4 mmHg) than 2K1C-C ( p <0.01). There were no significant differences between SHAM-HES (122±7 mmHg) and SHAM-C. MAP at the end of the protocol were similar to in SBP. ANOVA revealed mRNA expression of eNOS was significantly higher in 2K1C than in SHAM ( p <0.05), and showed no significant difference between C and HES, nor a significant interaction. Conclusion: Continuous intake of HES may suppress BP increase in 2K1C. The role of eNOS mRNA expression may not be involved in the mechanism.


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