BIOELECTRIC IMPEDANCE OF THE BODY OF WISTAR RATS OF BOTH SEXES WITH A MONOCROTALINE MODEL OF PULMONARY ARTERIAL HYPERTENSION

2020 ◽  
Vol 17 (2) ◽  
pp. 98-109
Author(s):  
N.L. Kolomeyets ◽  
◽  
O.V. Syslonova ◽  
S.L. Smirnova ◽  
I.M. Roshchevskaya ◽  
...  
Keyword(s):  
Pulmonary Hypertension ◽  
Right Ventricle ◽  
Amplitude Ratio ◽  
Bioelectrical Impedance ◽  
The Body ◽  
Female Rats ◽  
Male Rats ◽  
High Current ◽  
Bioelectric Impedance ◽  
The Right

The aim of the work was to study the bioelectric impedance of the body in rats of both genders with monocrotaline-induced pulmonary hypertension. Materials and methods. Multi-frequency bioimpedance studies of the body of rats of both genders were carried out one month after the administration of monocrotaline (dose of 60 mg/kg, subcutaneously). Results. Hypertrophy of the right ventricle of the heart was revealed in animals with experimentally induced pulmonary hypertension, with a significantly greater thickness of the free wall of the right ventricle in males compared to females. Significant influence of the interaction of the gender factor and the effect of monocrotaline on the indicators of the bioelectric impedance of the body (amplitude, ratio of resistances at low and high current frequencies) was shown using the method of analysis of variance. The body bioelectric impedance amplitudes, normalized to body length, were significantly lower in the male rats and higher in the female rats with experimental pulmonary hypertension compared to the control animals of the same gender. In the female rats with the monocrotaline model of pulmonary hypertension, the ratio of the amplitudes of the bioelectric impedance of the body at low and high current frequencies was significantly lower than in the control animals. Conclusion. Changes in the body resistance of the rats with pulmonary hypertension indicate an inflammatory process. Gender differences in the changes in the bioelectrical impedance of the body indicate a more severe manifestation of pulmonary hypertension in the males.

scholarly journals Pulmonary hypertension after pneumonectomy: a preclinical model in rats and human pulmonary endothelial cells

2020 ◽  
Vol 59 (1) ◽  
pp. 147-154
Author(s):  
Pierre Sentenac ◽  
Gianluca Samarani ◽  
Patrice Bideaux ◽  
Pierre Sicard ◽  
Benjamin Bourdois ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Pulmonary Hypertension ◽  
Shear Stress ◽  
Right Ventricle ◽  
Cyclic Stretch ◽  
Male Rats ◽  
Pulmonary Endothelial Cells ◽  
The Right ◽  
The Impact

Abstract OBJECTIVES Pulmonary hypertension and heart disease contribute to the high morbidity rate following pneumonectomy (PN). The pathophysiology is still poorly understood. The objective was to investigate the consequences of PN on cardiopulmonary function in rats and to explore in vitro the involved mechanisms. METHODS Sixty Sprague-Dawley male rats randomly underwent either a right PN (PN group) or sham surgery. Ten rats per group were sacrificed on postoperative days 3, 7 and 28. Cardiopulmonary alterations were investigated by echocardiographic, haemodynamic and histological analyses. In vitro, the shear stress was reproduced using a Flexcell Tension™ cyclic stretch on cultured human pulmonary endothelial cells (P-ECs) to investigate the impact on pulmonary artery smooth muscle cell (PA-SMC) growth. Data are expressed as mean ± SD. RESULTS Mean pulmonary arterial pressure gradually increased in the PN group to reach 35 ± 7 mmHg on postoperative day 28 vs 18 ± 4 in sham (P = 0.001), likewise the proportion of muscularized distal pulmonary arteries, 83 ± 1% vs 5 ± 1%, respectively (P < 0.001), related to in situ PA-SMC proliferation. The right ventricle area and lateral wall thickness were doubled in the PN group on postoperative day 28. The left ventricle ejection fraction decreased on postoperative days 7 and 28 while the right ventricle function was maintained. In vitro, the human PA-SMC growth was significantly greater when seeded with stretched vs non-stretched P-EC media, highlighting the role of shear stress on the P-EC paracrine function. CONCLUSIONS Right PN led to pulmonary hypertension and proportional right heart remodelling in rats. The shear stress related to high blood flow alters the pulmonary endothelial paracrine control of SMC growth.

120-Day study of cardiac output in unanesthetized rats

1964 ◽  
Vol 207 (4) ◽  
pp. 767-770 ◽  
Author(s):  
Vojin P. Popovic ◽  
Kenneth M. Kent
Keyword(s):  
Cardiac Output ◽  
Right Ventricle ◽  
Venous Blood ◽  
Mean Value ◽  
The Body ◽  
Male Rats ◽  
Laboratory Animals ◽  
Fick Principle ◽  
Venous Cannula ◽  
The Right

The technique of permanent cannulation of the aorta and right atrium which permits the simultaneous sampling of arterial and venous blood in unanesthetized small laboratory animals was modified so that the venous cannula is inserted in the right ventricle and the patency of the cannulas increased to well over 100 days. After cannulation rats were used for cardiac output determinations (Fick principle). The animals were unanesthetized and unrestrained. Oxygen consumption, oxygen contents of the blood, and cardiac output were determined seven times in 98 adult male rats during a period of 120 days. The mean value of the cardiac index was 286 ± 25 ml/min kg, remaining unchanged during a period in which the body weight of the animals increased from 300 to 500 g. The results indicate that the technique of permanent cannulation of the aorta and the right ventricle offers a reliable and reproducible method for cardiac output determinations in unanesthetized and unrestrained rats during a period of several months after the cannulation.

scholarly journals Protective effect of nicotinamide and l-arginine against monocrotaline-induced pulmonary hypertension in rats: gender dependence

2020 ◽  
Vol 72 (5) ◽  
pp. 1334-1346
Author(s):  
Katarzyna Sztormowska-Achranowicz ◽  
Zbigniew Jankowski ◽  
Ivan Kocić
Keyword(s):  
Pulmonary Hypertension ◽  
Right Ventricle ◽  
Morphological Changes ◽  
Female Rats ◽  
Positive Role ◽  
Pulmonary Vascular Remodeling ◽  
Male And Female ◽  
Male And Female Rats ◽  
The Right ◽  
Gender Dependence

Abstract Background The purpose of this paper was to examine the effects of nicotinamide (ND) and l-arginine (l-ARG) on pulmonary vascular and heart changes induced by pulmonary hypertension in rats in a gender-dependent way. Methods Experiments were performed on male (M) and female (F) rats. PAH was induced via monocrotaline injection (sc, 60/kg B.W.) on day one of the 23-day observational period. After that, the animals were sacrificed, hearts removed and weighed and the papillary muscles isolated to measure force of contraction (Fc). Morphological changes of pulmonary vessels were also examined. Results Mixed diet supplementation with l-ARG + ND prevented highly significant right ventricle enlargement induced by PAH in both, male and female rats. Weight ratios between the right ventricle (RV) on one side and the left ventricle with septum on the other (LV + S) decreased from 0.46 ± 0.016 g to 0.29 ± 0.006 g in males and from 0.63 ± 0.03 g to 0.24 ± 0.008 g in females, n = 6, p < 0.001. Additionally, PAH increased basal contractility in female groups, and each of the diet allocations (l-ARG, ND, and mixed) were found to restore contractility to control values. All diet protocols in male and female restored decreased responsiveness of the myocardium to norepinephrine in hearts obtained from rats with PAH and prevented vascular changes observed in pulmonary hypertension (thickness of blood vessels and cell infiltration). Conclusion Our study suggests that l-arginine, nicotinamide or both play a positive role in right ventricle function or the process reducing pulmonary vascular remodeling especially in a gender-independent way.

CMR markers for early right ventricular dysfunction in precapillary pulmonary hypertension

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
J Vos ◽  
T Leiner ◽  
A.P.J Van Dijk ◽  
F.J Meijboom ◽  
G.T Sieswerda ◽  
...  
Keyword(s):  
Pulmonary Hypertension ◽  
Right Ventricle ◽  
Right Ventricular ◽  
Circumferential Strain ◽  
Peak Strain ◽  
Healthy Controls ◽  
Free Wall ◽  
Global Circumferential Strain ◽  
The Right ◽  
Rv Function

Abstract Introduction Precapillary pulmonary hypertension (pPH) causes right ventricular (RV) pressure overload inducing RV remodeling, often resulting in dysfunction and dilatation, heart failure, and ultimately death. The ability of the right ventricle to adequately adapt to increased pressure loading is key for patients' prognosis. RV ejection fraction (RVEF) by cardiac magnetic resonance (CMR) is related to outcome in pPH patients, but this global measurement is not ideal for detecting early changes in RV function. Strain analysis on CMR using feature tracking (FT) software provides a more detailed assessment, and might therefore detect early changes in RV function. Aim 1) To compare RV strain parameters in pPH patients and healthy controls, and 2) to compare strain parameters in a subgroup of pPH patients with preserved RVEF (pRVEF) and healthy controls. Methods In this prospective study, a CMR was performed in pPH patients and healthy controls. Using FT-software on standard cine images, the following RV strain parameters were analyzed: global, septal, and free wall longitudinal strain (GLS, sept-LS, free wall-LS), time to peak strain (TTP, as a % of the whole cardiac cycle), the fractional area change (FAC), global circumferential strain (GCS), global longitudinal and global circumferential strain rate (GLSR and GCSR, respectively). A pRVEF is defined as a RVEF &gt;50%. To compare RV strain parameters in pPH patients to healthy controls, the Mann-Whitney U test was used. Results 33 pPH-patients (55 [45–63] yrs; 10 (30%) male) and 22 healthy controls (40 [36–48] yrs; 15 (68%) male) were included. All RV strain parameters were significantly reduced in pPH patients compared to healthy controls (see table), except for GCS and GCSR. Most importantly, in pPH patients with pRVEF (n=8) GLS (−26.6% [−22.6 to −27.3] vs. −28.1% [−26.2 to −30.6], p=0.04), sept-LS (−21.2% [−19.8 to −23.2] vs. −26.0% [−24.0 to −27.9], p=0.005), and FAC (39% [35–44] vs. 44% [42–47], p=0.02) were still significantly impaired compared to healthy controls. The RV TTP was significantly increased in pPH patients compared to healthy controls (47% [44–57] vs. 40% [33–43], p≤0.001). Conclusions Several CMR-FT strain parameters of the right ventricle are impaired in pPH patients when compared to healthy controls. Moreover, even in pPH patients with a preserved RVEF multiple RV strain parameters (GLS, sept-LS, and FAC) remained significantly impaired, and TTP significantly prolonged, in comparison to healthy controls. This suggests that RV strain parameters may be used as an early marker of RV dysfunction in pPH patients. Funding Acknowledgement Type of funding source: None

scholarly journals Age-Related Effects on Right Femoral Bone of Male Wistar Rats: A Morphometric and Biomechanical Study

2021 ◽  
Author(s):  
Sheila Martins Puelker ◽  
Sonia Regina Ribeiro de Castro ◽  
Romeu Rodrigues de Souza ◽  
Laura Beatriz Mesiano Maifrino ◽  
Ricardo Aparecido Baptista Nucci ◽  
...  
Keyword(s):  
Cortical Thickness ◽  
Wistar Rats ◽  
Female Rats ◽  
Male Rats ◽  
Aged Rats ◽  
Femoral Bone ◽  
Middle Aged ◽  
Left Femur ◽  
Bone Stiffness ◽  
The Right

Abstract Introduction Study of the variations of bone characteristics with age in different animal models is important to design musculoskeletal studies. Thus, this study aimed to evaluate the bone mass, dimensions, and biomechanical parameters of the femur in young, middle-aged, and aged Wistar rats. Materials and Methods Thirty male rats (Rattus norvegicus) were divided in three groups (n = 10 per group)—3-month-old young rats, 12-month-old middle-aged rats, and 18-months-old aged rats. The right femurs were subjected sequentially to morphometric study (bone weight, cortical thickness) and biomechanical tests (maximum resistance strength and bone stiffness). Results We observed a significant increase in femur histological (cortical thickness) and biomechanical (maximum strength and bone stiffness) parameters with aging when compared with young animals. Conclusions With the advancing age, the right femoral bone of middle-aged and old animals had greater variations when compared with young animals. However, further studies with the aid of a comparison between right and left femur and other long bones in both male and female rats are needed to corroborate with our findings.

scholarly journals Effects of ovariectomy on antioxidant defence systems in the right ventricle of female rats with pulmonary arterial hypertension induced by monocrotaline

2018 ◽  
Vol 96 (3) ◽  
pp. 295-303 ◽  
Author(s):  
Rafaela Siqueira ◽  
Rafael Colombo ◽  
Adriana Conzatti ◽  
Alexandre Luz de Castro ◽  
Cristina Campos Carraro ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Pulmonary Arterial Hypertension ◽  
Right Ventricle ◽  
Protein Expression ◽  
Arterial Hypertension ◽  
Female Rats ◽  
Antioxidant Defenses ◽  
Thioredoxin 1 ◽  
Pulmonary Arterial ◽  
The Right

The aim of this study was to evaluate the impact of ovariectomy on oxidative stress in the right ventricle (RV) of female rats with pulmonary arterial hypertension (PAH) induced by monocrotaline (MCT). Rats were divided into 4 groups (n = 6 per group): sham (S), sham + MCT (SM), ovariectomized (O), and ovariectomized + MCT (OM). MCT (60 mg·kg−1 i.p.) was injected 1 week after ovariectomy or sham surgery. Three weeks later, echocardiographic analysis and RV catheterisation were performed. RV morphometric, biochemical, and protein expression analysis through Western blotting were done. MCT promoted a slight increase in pulmonary artery pressure, without differences between the SM and OM groups, but did not induce RV hypertrophy. RV hydrogen peroxide increased in the MCT groups, but SOD, CAT, and GPx activities were also enhanced. Non-classical antioxidant defenses diminished in ovariectomized groups, probably due to a decrease in the nuclear factor Nrf2. Hemoxygenase-1 and thioredoxin-1 protein expression was increased in the OM group compared with SM, being accompanied by an elevation in the estrogen receptor β (ER-β). Hemoxygenase-1 and thioredoxin-1 may be involved in the modulation of oxidative stress in the OM group, and this could be responsible for attenuation of PAH and RV remodeling.

scholarly journals The Role of G Protein-Coupled Receptors in the Right Ventricle in Pulmonary Hypertension

2018 ◽  
Vol 5 ◽  
Author(s):  
Gayathri Viswanathan ◽  
Argen Mamazhakypov ◽  
Ralph T. Schermuly ◽  
Sudarshan Rajagopal
Keyword(s):  
Pulmonary Hypertension ◽  
Right Ventricle ◽  
G Protein ◽  
G Protein Coupled Receptors ◽  
The Right ◽  
G Protein Coupled

scholarly journals Right Ventricular Function in Acute Respiratory Distress Syndrome: Impact on Outcome, Respiratory Strategy and Use of Veno-Venous Extracorporeal Membrane Oxygenation

2022 ◽  
Vol 12 ◽  
Author(s):  
Matthieu Petit ◽  
Edouard Jullien ◽  
Antoine Vieillard-Baron
Keyword(s):  
Pulmonary Hypertension ◽  
Extracorporeal Membrane Oxygenation ◽  
Right Ventricle ◽  
Pulmonary Circulation ◽  
Distress Syndrome ◽  
Cor Pulmonale ◽  
Prone Positioning ◽  
Acute Cor Pulmonale ◽  
Membrane Oxygenation ◽  
The Right

Acute respiratory distress syndrome (ARDS) is characterized by protein-rich alveolar edema, reduced lung compliance and severe hypoxemia. Despite some evidence of improvements in mortality over recent decades, ARDS remains a major public health problem with 30% 28-day mortality in recent cohorts. Pulmonary vascular dysfunction is one of the pivot points of the pathophysiology of ARDS, resulting in a certain degree of pulmonary hypertension, higher levels of which are associated with morbidity and mortality. Pulmonary hypertension develops as a result of endothelial dysfunction, pulmonary vascular occlusion, increased vascular tone, extrinsic vessel occlusion, and vascular remodeling. This increase in right ventricular (RV) afterload causes uncoupling between the pulmonary circulation and RV function. Without any contractile reserve, the right ventricle has no adaptive reserve mechanism other than dilatation, which is responsible for left ventricular compression, leading to circulatory failure and worsening of oxygen delivery. This state, also called severe acute cor pulmonale (ACP), is responsible for excess mortality. Strategies designed to protect the pulmonary circulation and the right ventricle in ARDS should be the cornerstones of the care and support of patients with the severest disease, in order to improve prognosis, pending stronger evidence. Acute cor pulmonale is associated with higher driving pressure (≥18 cmH2O), hypercapnia (PaCO2 ≥ 48 mmHg), and hypoxemia (PaO2/FiO2 &lt; 150 mmHg). RV protection should focus on these three preventable factors identified in the last decade. Prone positioning, the setting of positive end-expiratory pressure, and inhaled nitric oxide (INO) can also unload the right ventricle, restore better coupling between the right ventricle and the pulmonary circulation, and correct circulatory failure. When all these strategies are insufficient, extracorporeal membrane oxygenation (ECMO), which improves decarboxylation and oxygenation and enables ultra-protective ventilation by decreasing driving pressure, should be discussed in seeking better control of RV afterload. This review reports the pathophysiology of pulmonary hypertension in ARDS, describes right heart function, and proposes an RV protective approach, ranging from ventilatory settings and prone positioning to INO and selection of patients potentially eligible for veno-venous extracorporeal membrane oxygenation (VV ECMO).

Acute and sub-chronic toxicity of the aqueous extract of Ficus vogelii (Miq.) Miq. stem bark in rats

2021 ◽  
Vol 10 (2) ◽  
pp. 89-97
Author(s):  
EL Lappa ◽  
◽  
C Bogning Zangueu ◽  
EL Nguemfo ◽  
JJ Kojom Wanche ◽  
...  
Keyword(s):  
Body Weight ◽  
Aqueous Extract ◽  
Chronic Toxicity ◽  
Hematological Parameters ◽  
Lethal Dose ◽  
Relative Weight ◽  
Stem Bark ◽  
The Body ◽  
Female Rats ◽  
Male Rats

Ficus vogelii is a medicinal plant mainly found in tropical Africa and reported to treat inflammatory complaints. This study aims to evaluate the acute and sub-chronic toxicity of the aqueous extract of Ficus vogelii stem bark in wistar rats. For acute study, aqueous extract at a single dose of 5000 mg/kg body weight was administered to female rats and observed for 14 days. In the sub-chronic study, the extract was administered daily to both sex rats at the doses of 100, 200, 400, and 600 mg/kg body weight for 28 consecutive days. Body weight was measured weekly, while hematological, biochemical, and histopathological parameters were analyzed after euthanize. Aqueous extract of Ficus vogelii at all tested doses didn’t produced any mortality or significant change on the body weight and relative weight of rats on acute and sub-chronic studies. The lethal dose 50 was estimated greater than 5000 mg/kg (DL50˃5000 mg/kg). Hematological parameters were recorded non-significant in all treated rats. Aqueous extract at 600 mg/kg significantly changed transaminases and alkaline phosphatase activities, these changes were reversible in satellites. The concentrations of bilirubin was increased at 200 and 600 mg/kg in male rats, at 100, 400 mg/kg in female rats. The levels of lipids markers didn’t changed, except the significant decrease of LDL-cholesterol. Histological examination didn’t showed any change in the architecture of the liver and kidney of rats treated compared to control. Thus aqueous extract of Ficus vogelii stem bark didn’t produced adverse effects in rats after oral acute and sub-chronic treatment.

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