Evidence for a Decreased Noradrenaline Sensitivity in Mesenteric Resistance Vessels from Rats with Chemical Renal Medullectomy

1989 ◽  
Vol 77 (2) ◽  
pp. 167-170 ◽  
Author(s):  
S. J. Bund ◽  
A. M. Heagerty ◽  
A. Fletcher ◽  
J. D. Swales
Keyword(s):  
Blood Pressure ◽  
Body Weight ◽  
Intraperitoneal Injection ◽  
Wistar Rats ◽  
Vascular Reactivity ◽  
Morphological Changes ◽  
Pressor Responses ◽  
Resistance Vessels

1. Chemical renal medullectomy was performed in Wistar rats by intraperitoneal injection of 2-bromoethylamine hydrobromide (200 mg/kg body weight). The effect of this treatment upon blood pressure and mesenteric vascular reactivity and morphology was studied 3 weeks after treatment. 2. Blood pressure was significantly raised in medull-ectomized rats. The indirect systolic pressures (means ± sem) were 112 ± 2.4 mmHg (14.9 ± 0.32 kPa) and 123 ± 3.5 mmHg (16.4 ± 0.5 kPa) (P < 0.02) for control (n = 12) and medullectomized (n = 12) rats, respectively. However, there were no significant changes in the morphology of the mesenteric resistance vessels. 3. Maximum pressor responses and Ca2+ sensitivities were unchanged in these vessels compared with controls, but the sensitivity to noradrenaline was significantly reduced. Noradrenaline pD2 (= −log ED50) values (means ± sem) were 5.87 ± 0.03 and 5.69 ± 0.08 (P < 0.05) for control (n = 12) and medullectomized (n = 12) rats, respectively. 4. This study demonstrates that in this model of hypertension the noradrenaline sensitivity is reduced in mesenteric resistance vessels, but there are no detectable morphological changes associated with the rise in blood pressure.

Critical opening pressure and reactivity of tail vessels in conscious hypertensive rats

1976 ◽  
Vol 54 (3) ◽  
pp. 314-321
Author(s):  
A. C. Darke ◽  
P. G. Nair ◽  
P. Gaskell
Keyword(s):  
Blood Pressure ◽  
Renovascular Hypertension ◽  
Vascular Reactivity ◽  
Experimental Hypertension ◽  
Hypertensive Rats ◽  
Opening Pressure ◽  
Critical Opening ◽  
Resistance Vessels ◽  
Before And After ◽  
Desoxycorticosterone Acetate

The possible role of increased vascular reactivity in the mechanism of experimental hypertension was studied by measurements of the critical opening pressure (COP) of tail vessels in conscious rats. In hypertension induced by administration of desoxycorticosterone acetate (DOCA) and replacement of the drinking water by 1% NaCl solution (DOCA–NaCl hypertension), and in one-kidney Goldblatt renovascular hypertension, the raised level of blood pressure was associated with an increased COP of the tail vessels when measured both before and after ganglionic blockade. In rats treated with either DOCA alone or 1% NaCl alone there was no significant increase in systolic blood pressure (SBP) or COP relative to the corresponding controls. In all four experimental series intravenous infusion of angiotensin or norepinephrine in conscious ganglion-blocked rats produced dose-dependent increases in SBP and COP. In DOCA–NaCl hypertensive rats but not in renovascular hypertensives, nor in rats treated with DOCA alone or 1% NaCl alone, the increase in COP for a given increment in dose of angiotensin or norepinephrine was significantly greater than in the control rats. It is concluded that in DOCA–NaCl hypertension there is a true increase in the reactivity of the smooth muscle of the resistance vessels to angiotensin and norepinephrine. In renovascular hypertension this is not the case and other factors must therefore be involved in causing the increased blood pressure and COP.

scholarly journals To compare the blood pressure and heart rate during course of various types of anesthesia in wistar rat: A novel experiences

2018 ◽  
Vol 9 (6) ◽  
pp. 37-39
Author(s):  
Jagdish Narayan ◽  
Pradeep Kumar ◽  
Ankit Gupta ◽  
Sunita Tiwari
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Body Weight ◽  
Wistar Rats ◽  
Wistar Rat ◽  
Medical Sciences ◽  
The Awakening ◽  
Group I ◽  
Male Wistar Rats ◽  
Thiopental Sodium

Background: Rats are commonly used animals in development of newer drugs, rectification of toxicity and to record the various alterations in physiological parameters following pharmacological and non pharmacological interventions.Aim and Objectives: The purpose of this study was to identify the best physiological window during anesthesia. Therefore, we compared the effect of anesthesia using combination of ketamine and xylazine (KX) and thiopental sodium (intraperitoneally) on blood pressure and heart rate in adult male Wistar rats. Material and Methods: Twelve, male Wistar rats with a mean body weight of 260 ± 15 g were acquired. Thiopental sodium and cocktail of ketamine and xylazine (KX) were administered (ip) in group- I and group-II respectively. The systolic blood pressure and heart rate was recorded in both the groups till the awakening phase.Results: We found that there was a constant SBP and HR in Ketamine/Xylezine groups that are from 30 to 90 minutes after injection of anesthesia while this window was not observed in thiopental group.Conclusion: Our study concludes that the best time to observe the effect of newer drug during period between 30- 90 minutes after anesthesia.Asian Journal of Medical Sciences Vol.9(6) 2018 37-39

scholarly journals Protective Effect of Sodium Tetraborate on Chromium-induced Brain Damage in Rats

2018 ◽  
Vol 11 (1) ◽  
pp. 227-236 ◽  
Author(s):  
Yerbolat Iztleuov ◽  
Talgar Abilov ◽  
Ganiya Zhanabayeva ◽  
Irina Ismailova ◽  
Marat Iztleuov
Keyword(s):  
Body Weight ◽  
Intraperitoneal Injection ◽  
Wistar Rats ◽  
Neuroprotective Effect ◽  
Sodium Tetraborate ◽  
High Toxicity ◽  
Protein Thiol ◽  
Group 4 ◽  
Single Intraperitoneal Injection ◽  
Mda Content

Hexavalent chromium presents a particular threat due to its high toxicity. In this study showed the neuroprotective effect of sodium tetraborate in chromic intoxication. The experiment was performed on Wistar rats divided into 4 groups: 1 group - control; 2 group - single intraperitoneal injection of K2Сr2O7 in a dose of 0,5LD50, in the 3 and 4 groups with drinking water received Na2B4O7. Animals of the 3 group - 4 mg/kg of body weight, in 4 group - 72 mg/kg of body weight daily for 10 days, the last administration of Na2B4O7 was combined with a single intraperitoneal injection of K2Сr2O7 at a dose of 14 mg/kg (0,5LD50). Na2B4O7 in a dose of 4 mg/kg leads to a decrease in the level of MDA by 33%, an increase in the activity of catalase by 69%, superoxide dismutase by 21%, GR by 49%. Na2B4O7 at a dose of 72 mg/kg increases the MDA content by 31% in comparison with the data of rats of chromic intoxication. K2Сr2O7 reduces the GSH level by 42%, the non-protein thiol by 36%. Na2B4O7 at a dose of 4 mg/kg increased the GSH level by 53%, the non-protein thiol by 35%, and at a dose of 72 mg/kg reduced the GSH content by 23% (ρ<0.05), the non-protein thiol by 20% (ρ<0.05) in comparison with the data of rats exposed to K2Сr2O7.

scholarly journals Prolonged Administration of Rudgea viburnoides (Cham.) Benth. Prevents Impairment of Redox Status, Renal Dysfunction, and Cardiovascular Damage in 2K1C-Hypertensive Rats by Inhibiting ACE Activity and NO-GMPC Pathway Activation

Pharmaceutics ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1579
Author(s):  
Fernanda Viana Paulin ◽  
Rhanany Alan Calloi Palozi ◽  
Bethânia Rosa Lorençone ◽  
Arthur Ladeira Macedo ◽  
Lucas Pires Guarnier ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Wistar Rats ◽  
Vascular Reactivity ◽  
Redox Status ◽  
Converting Enzyme ◽  
Hypertensive Rats ◽  
Prolonged Administration ◽  
Cardiovascular Damage ◽  
Cgmp Pathway

Rudgea viburnoides is widely found in the Brazilian Cerrado, and commonly used in Brazilian folk medicine. In this study, we evaluated the effects of prolonged administration of the aqueous extract from R. viburnoides leaves (AERV) on impaired redox status, renal dysfunction, and cardiovascular damage in 2K1C hypertensive rats, as well as its chemical composition by LC-DAD-MS. Renal hypertension (two kidney, one-clip model) was surgically induced in male Wistar rats and AERV (30, 100 and 300 mg/kg) was administered orally five weeks after surgery for 28 days. Renal function was assessed and urinary electrolytes, pH, and density were measured. Electrocardiography, blood pressure and heart rate were recorded. Cardiac and mesenteric vascular beds were isolated for cardiac morphometry and evaluation of vascular reactivity, and aortic rings were also isolated for measurement of cyclic guanosine monophosphate levels, and the redox status was assessed. Prolonged treatment with AERV preserved urine excretion and electrolyte levels (Na+, K+, Ca2+ and Cl−), reversed electrocardiographic changes, left ventricular hypertrophy and changes in vascular reactivity induced by hypertension, and reduced blood pressure and heart rate. This effect was associated with a positive modulation of tissue redox state, activation of the NO/cGMP pathway, and inhibition of the angiotensin-converting enzyme. Glycosylated iridoids, chlorogenic acids, glycosylated triterpenes, O-glycosylated flavonols, and triterpenoid saponins were annotated. AERV showed no acute toxicity in female Wistar rats. Therefore, AERV treatment reduced the progression of cardiorenal disease in 2K1C hypertensive rats, which can be involved with an important attenuation of oxidative stress, angiotensin-converting enzyme inhibition, and activation of the NO/cGMP pathway.

Vascular Reactivity in Post-Deoxycorticosterone Hypertension in Rats and its Relation to ‘Irreversible’ Hypertension in Man

1972 ◽  
Vol 42 (5) ◽  
pp. 579-590 ◽  
Author(s):  
L. J. Beilin ◽  
G. Ziakas
Keyword(s):  
Blood Pressure ◽  
High Pressure ◽  
Vascular Reactivity ◽  
Renal Hypertension ◽  
Peripheral Resistance ◽  
Systemic Resistance ◽  
Wall Thickening ◽  
Resistance Vessels ◽  
Arteriolar Wall ◽  
Rat Tail

1. The mechanism by which the blood pressure remains elevated after temporary administration of deoxycorticosterone (DOCA) and saline has been studied by comparing vascular reactivity in the resistance bed of the isolated perfused rat tail in animals with post-DOCA hypertension and normotensive controls. 2. Animals with post-DOCA hypertension showed increased arteriolar responses to noradrenaline and 5-hydroxytryptamine, increased maximum contractile responses to noradrenaline, and increased resistance to flow under conditions of maximum vasodilation. 3. These abnormalities may be explained largely on the basis of arteriolar wall thickening resulting from hypertension and they will lead to a high peripheral resistance. 4. Evidence from experiments on chronic renal hypertension indicates that hypertension only becomes irreversible when the ability of the kidneys to regulate blood pressure is impaired. When this has occurred the high resistance offered by abnormal systemic arterioles will be a significant factor in maintaining a high arterial pressure and the high pressure will in turn continue to exert deleterious effects on resistance vessels, including those of the kidney. 5. It is suggested that persistence of hypertension in patients in whom the initial cause of the hypertension has apparently been removed is due to changes in morphology and reactivity of renal and systemic resistance vessels similar to those described in arterioles of animals with post-DOCA hypertension.

Morphological and functional characteristics of isolated resistance vessels in advanced uraemia

1986 ◽  
Vol 71 (6) ◽  
pp. 657-663 ◽  
Author(s):  
C. Aalkjær ◽  
E. B. Pedersen ◽  
H. Danielsen ◽  
O. Fjeldborg ◽  
B. Jespersen ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Angiotensin Ii ◽  
Vascular Reactivity ◽  
Subcutaneous Fat ◽  
Mean Blood Pressure ◽  
Internal Diameter ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Vascular Morphology ◽  
Resistance Vessels

1. In order to obtain direct information on the properties of the resistance vasculature of patients with advanced uraemia, a technique was developed to dissect out small arteries (internal diameter about 165 μm) from biopsies of subcutaneous fat. 2. Such arteries responded in a concentration-dependent manner to noradrenaline and angiotensin II, and the maximal force developed suggested that the vessels were fully viable. 3. Although the biopsies were normally taken during operations under general anaesthesia, biopsies taken under local anaesthesia also appeared to be fully viable, suggesting that this technique may prove useful as a general method for studying the intrinsic vascular properties of humans. 4. Biopsies were taken from 20 patients with uraemia, all of whom were treated with chronic intermittent dialysis, and 11 control subjects; up to three vessels were examined per biopsy. 5. The uraemic state was not associated with changes in vascular morphology, or in vascular reactivity or sensitivity to noradrenaline, angiotensin II, potassium or calcium. However, for the uraemic patients and for the controls there was a positive correlation between mean blood pressure and the ratio of vessel media thickness to lumen diameter, as well as a negative correlation between mean blood pressure and vessel active media stress. 6. The results suggest that uraemia treated with dialysis may not be associated with altered properties of the resistance vasculature. However, it appears that uraemic hypertension is associated with both morphological and functional abnormalities of the resistance vasculature.

Impact of Brazil Nut (Bertholletia excelsa, H.B.K.) Supplementation on Body Composition, Blood Pressure, and the Vascular Reactivity of Wistar Rats When Submitted to a Hypersodium Diet

2021 ◽  
pp. 1-10
Author(s):  
Henrique Saldanha Melo ◽  
Juliana Arruda de Souza Monnerat ◽  
Nathalia da Silva Costa ◽  
Thais Bento Bernardes ◽  
D’Angelo Carlo Magliano ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Body Composition ◽  
Wistar Rats ◽  
Vascular Reactivity ◽  
Brazil Nut ◽  
Bertholletia Excelsa

The Effect of Exercise and Protein Source on Food Intake Regulation and Characteristics of Metabolic Syndrome in Obese Female Wistar Rats

2019 ◽  
Vol 15 (2) ◽  
pp. 175-184
Author(s):  
Alireza Jahan-Mihan ◽  
Peter Magyari ◽  
Shawna Jenkins ◽  
Valeria Palamidy ◽  
Lindsay Pappas ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Metabolic Syndrome ◽  
Body Weight ◽  
Food Intake ◽  
Whey Protein ◽  
Soy Protein ◽  
Wistar Rats ◽  
Protein Diet ◽  
Obese Female ◽  
Female Wistar Rats

Background: Beneficial effects of dietary proteins and exercise in treatment of obesity is well-recognized. The effect of exercise and protein source on food intake, body weight and characteristics of metabolic syndrome in obese female Wistar rats was examined. Female Wistar rats received an obesogenic diet for 12 weeks. Then, rats were allocated to four groups and received one of the following treatments for eight weeks: 1- Whey protein Diet + Exercise (WPE), 2- Soy protein diet + exercise (SPE), 3- Whey protein diet, no exercise (WPN), 4- Soy protein diet, no exercise (SPN). The exercise comprised of 30 minutes on a treadmill, three times/week. Body weight (BW) and food intake (FI), blood pressure, pulse, glucose and intake regulatory hormones were measured. Results: FI and plasma ghrelin (2.7 times) were higher in exercise groups compared with non-exercise groups. BW was lower (6.7%) in groups fed a whey protein diet compared with those fed a soy protein diet. Abdominal fat (% BW) was lower (22.8%) in WPE compared with other groups. Diastolic blood pressure (11.1%) and pulse (6%) were lower in groups fed a soy protein diet compared with groups fed a whey protein diet. Conclusion: While exercise affects food intake, source of protein determines BW and BC. Whey protein showed more favorable effect on BW and body composition.

Effect of chronic intracerebroventricular dexamethasone on blood pressure in normotensive rats

1993 ◽  
Vol 264 (6) ◽  
pp. E843-E847 ◽  
Author(s):  
G. Tonolo ◽  
A. Soro ◽  
P. Madeddu ◽  
C. Troffa ◽  
M. G. Melis ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Body Weight ◽  
Wistar Rats ◽  
Glucocorticoid Receptors ◽  
Body Weight Gain ◽  
Peripheral Vascular ◽  
Weight Range ◽  
Entire Experiment ◽  
The Brain

We report herein the effects of long-term intracerebroventricular (icv) dexamethasone in normotensive rats. Dexamethasone (0.002, 0.02, 0.2, and 2.0 micrograms/day) or its vehicle (0 microgram/day, n = 8 each group) was infused icv via subcutaneous miniosmotic pumps (Alzet 2002) for 24 days in male conscious Wistar rats (weight range 190-240 g). Eighteen Wistar rats (weight range 200-230 g) received either vehicle or dexamethasone (0.2 and 2 micrograms/day) subcutaneously (sc) for 24 days. Systolic blood pressure (SBP, tail cuff) and body weight were recorded two times a week in the trained conscious rats. Dexamethasone (0.2 micrograms/day icv) exerted a progressive significant decrease in SBP over 24 days compared with both rats receiving vehicle and to pretreatment values (108 +/- 4 vs. 122 +/- 4 and 120 +/- 2 mmHg, P < 0.01). As previously reported, a significant increase in SBP was observed after 6 days in rats given 2 micrograms/day sc dexamethasone compared with both rats receiving vehicle and to pretreatment values (150 +/- 4 vs. 122 +/- 2 and 120 +/- 2 mmHg, P < 0.01 for both). Thereafter, SBP remained at plateau for the entire experiment. A similar significant decrease in body weight gain with age was observed in rats given icv or sc dexamethasone. Our data suggest that the glucocorticoid receptors exert opposite effects on blood pressure when stimulated at the brain level instead of at the peripheral vascular level.

Subchronic oral toxicity study of Habb-e-Suranjan in albino Wistar rats

2018 ◽  
Vol 15 (3) ◽  
Author(s):  
Khalid Ghazanfar ◽  
Showkat A Dar ◽  
Tazeen Nazir ◽  
Seema Akbar
Keyword(s):  
Body Weight ◽  
Wistar Rats ◽  
Morphological Changes ◽  
The Body ◽  
Feed Consumption ◽  
Oral Toxicity ◽  
Significant Difference ◽  
Water Feed ◽  
Overnight Fasting ◽  
Toxic Potential

AbstractBackgroundHabb-e-Suranjan(HS) is a Unani pharmacopoeial formulation used for treatment of rheumatoid arthritis. The present study was carried to evaluate the toxic potential of HS in albino Wistar rats.MethodsThe subchronic was carried out at the dose levels of 2440 mg/kg of body weight in both sexes. The rats were observed carefully for any behavioral change for next 24 hours (hr) after the administration of the drug and daily twice thereafter till the completion of experimentation. Water/feed consumption and body weight were recorded on weekly basis. The rats were sacrificed on 91st day after overnight fasting. Blood was collected for hematological and biochemical analysis. The rats were dissected and organs were observed for any morphological changes. Organ samples were collected for histological studies.ResultsThere were no incidences of mortality/morbidity found in any of the treated rats.HScaused no significant difference in the body weights as well as relative organs weights of treated groups when compared with the control groups. There were no significant changes found in any biochemical, hematological and histopathological parameters that could indicate any signs of toxicity.ConclusionsThe study suggests thatHSis safe and did not induce any adverse effect in rats.

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