Subcellular distribution of the enzymes of the malate-aspartate shuttle in rat heart and effect of experimental cardiac hypertrophy

1985 ◽  
Vol 5 (2) ◽  
pp. 95-100 ◽  
Author(s):  
Charalampos Mavrides ◽  
Borivoj Korecky
Keyword(s):  
Cardiac Hypertrophy ◽  
Growth Stimulation ◽  
Newborn Rats ◽  
Aortic Constriction ◽  
Adult Rats ◽  
Cardiac Growth ◽  
Specific Stimulus ◽  
Total Dna ◽  
Rate Limiting ◽  
Malate Aspartate Shuttle

The effect of experimental cardiac hypertrophy on the enzymes of the malate – aspartate shuttle aspartate aminotransferase (AAT) and malate dehydrogenase (MDH) was studied. (1) Aortic constriction in adult rats resulted in 25% cardiac hypertrophy in 2½–3 weeks. Total DNA (mg per heart) did not change. (2) The proportions of mitochondrial and cytosolic isozymes of AAT and MDH did not change as a result of cardiac hypertrophy. About two-thirds of each enzyme occurred in the mitochondrial form and one-third in the cytosolic form. (3) Total AAT in hypertrophic hearts, in enzyme units per mg DNA, increased by 24% compared to AAT content in the hearts of sham-operated animals. Total MDH did not change. SoIubilized protein increased by 20%. Normal hearts contained 10 times more enzyme units of MDH than of AAT. (4) Cardiac growth stimulation induced in newborn rats did not result in specific changes of either enzyme. It is suggested that true cardiac hypertrophy acts as a specific stimulus for the possibly rate-limiting enzyme AAT of the shuttle.

THE EFFECT OF DIFFERENT DEGREES OF SUBDIAPHRAGMATIC AORTIC CONSTRICTION ON HEART WEIGHT AND BLOOD PRESSURE OF NORMAL AND HYPOPHYSECTOMIZED RATS

1955 ◽  
Vol 33 (1) ◽  
pp. 985-994 ◽  
Author(s):  
Margaret Beznák
Keyword(s):  
Blood Pressure ◽  
Cardiac Hypertrophy ◽  
Blood Pressure Response ◽  
Pressure Response ◽  
Heart Weight ◽  
Aortic Constriction ◽  
Hypophysectomized Rats ◽  
Intact Rats

The aortae of groups of normal and hypophysectomized rats were constricted with rings of five different sizes (0.93, 0.83, 0. 74, 0.71, and 0.63 mm. diameter). In normal rats constriction caused an increase in heart weight and blood pressure which was the greater the narrower the constriction. If constriction exceeded 0.74 mm., cardiac hypertrophy reached extremely high values, while the blood pressure was lower than in groups with less constriction. The blood pressure response to Adrenalin or Infundin increased in proportion to the degree of constriction down to 0.74 mm.; greater constriction reduced the response. In hypophysectomized rats no degree of aortic constriction produced hypertension or cardiac hypertrophy, yet the increase in blood pressure after Adrenalin or Infundin was as great as in the normal intact rats.

scholarly journals Leonurine Attenuates Pressure-Overload Cardiac Hypertrophy Induced By Abdominal Aortic Constriction In Rats

2021 ◽  
Author(s):  
Ding Xiaoli ◽  
Yuan Qingqing ◽  
Qian Haibing
Keyword(s):  
Angiotensin Ii ◽  
Cardiac Hypertrophy ◽  
Pressure Overload ◽  
Ventricular Myocardium ◽  
Left Ventricular ◽  
Left Ventricular Myocardium ◽  
Ang Ii ◽  
Aortic Constriction ◽  
Qrt Pcr ◽  
Abdominal Aortic

Abstract Background: Myocardial hypertrophy occurs in many cardiovascular diseases. Leonurine (Leo) is commonly used for cardiovascular and cerebrovascular diseases. However, whether it can prevent cardiac hypertrophy is not known. The aim of this study was to investigate the effect and mechanism of Leonurine (Leo) against pressure-overload cardiac hypertrophy induced by abdominal aortic constriction (AAC) in rats. Methods: To answer this question, we prove it in the following way: Cardiac function was evaluated by hemodynamic; the left ventricle enlargement was measured by heart weight index (HWI) and left ventricular mass index (LVWI); myocardial tissue changes and myocardial cell diameter (MD) were determined by Hematoxylin and eosin (HE) staining; theβ-myosin heavy chain(β-MHC)and atrial natriuretic factor (ANF), which are recognized as a marker of cardiac hypertrophy, were determined by Real-time quantitative PCR (qRT-PCR), then another gene phospholipase C (PLC), inositol triphosphate (IP3), which associated with RAS were determined by Western blot(WB). angiotensin II (Ang II), angiotensin II type 1 receptor (AT1R) were determined by ELISA, WB and qRT-PCR methods. Finally, we measured the level of Ca2+ by microplate method and the protooncogene c-fos and c-myc mRNA in left ventricular myocardium by qRT-PCR.Results: Compare with control group, Leonurine can improve systolic dysfunction; inhibit the increase of left cardiac; inhibit myocardial cells were abnormally large and restrain the changes of cardiac histopathology; decrease the expression of β-MHC, ANF, Ang II, AT1R, c-fos and c-myc mRNA and the protein levels of PLC, IP3, AngII and AT1R in left ventricular myocardium, in addition, the content of Ca2+ also decrease. Conclusion: Therefore, Leonurine can inhibit cardiac hypertrophy induced by AAC and its effects may be associated with RAS.

Amino acid uptake regulation by cell growth in cultured hepatocytes isolated from fetal and adult rats

1992 ◽  
Vol 12 (2) ◽  
pp. 135-141 ◽  
Author(s):  
S. Leoni ◽  
S. Spagnuolo ◽  
M. Massimi ◽  
F. Terenzi ◽  
L. Conti Devirgiliis
Keyword(s):  
Amino Acid ◽  
Cell Growth ◽  
Growth Inhibition ◽  
Cell Density ◽  
Amino Acid Uptake ◽  
Growth Stimulation ◽  
Acid Uptake ◽  
Adult Rats ◽  
Dependent Growth ◽  
Differentiation Stage

Amino acid uptake mediated by system A was studied in cultured fetal and adult hepatocytes, subjected to growth stimulation by EGF and insulin, or to growth inhibition by high cell density. The mitogenic stimulation induced a strong transport increase only in fetal cells, while the cell density-dependent growth inhibition, probably mediated by molecules present on adult hepatocyte membranes, provoked the decrease of amino acid uptake only in the adult cells. The results indicate that the different modulation of amino acid transport by cell growth is dependent on the age and the differentiation stage of hepatocytes.

ANTAGONIZING THE CX3CR1 RECEPTOR MARKEDLY REDUCES DEVELOPMENT OF CARDIAC HYPERTROPHY AFTER TRANSVERSE AORTIC CONSTRICTION IN MICE

2021 ◽  
Vol Publish Ahead of Print ◽  
Author(s):  
Simona Nemska ◽  
Max Gassmann ◽  
Marie-Louise Bang ◽  
Nelly Frossard ◽  
Reza Tavakoli
Keyword(s):  
Cardiac Hypertrophy ◽  
Transverse Aortic Constriction ◽  
Aortic Constriction

Effect of Growth Hormone Preparations on Cardiac Hypertrophy and Blood Pressure of Hypophysectomized Rats

1956 ◽  
Vol 184 (3) ◽  
pp. 563-566 ◽  
Author(s):  
Margaret Beznák
Keyword(s):  
Blood Pressure ◽  
Growth Hormone ◽  
Cardiac Hypertrophy ◽  
Body Growth ◽  
Bovine Growth Hormone ◽  
Aortic Constriction ◽  
Hypophysectomized Rats ◽  
Crystalline Growth

Of three growth hormone preparations only one (PGH 163-208A, Armour) restored cardiac hypertrophy and hypertension on aortic constriction in hypophysectomized rats near to the level seen in normal rats. The same aortic constriction caused no increase in the weight of the heart and no hypertension in untreated hypophysectomized rats and in similar rats treated with a bovine growth hormone preparation (R 285-174, Armour) or crystalline growth hormone (Dr. Li, Berkeley). The different action of the three preparations was not connected with their effect on appetite and on body growth. ACTH, 5 mg/rat/day, caused adrenal hypertrophy in hypophysectomized rats without raising their blood pressure. The weight of the heart and particularly the blood pressure after aortic constriction were, however, greater in hypophysectomized rats treated with ACTH than in their nontreated controls.

scholarly journals LCZ696, an Angiotensin Receptor-Neprilysin Inhibitor, Improves Cardiac Hypertrophy and Fibrosis and Cardiac Lymphatic Remodeling in Transverse Aortic Constriction Model Mice

2020 ◽  
Vol 2020 ◽  
pp. 1-10 ◽  
Author(s):  
Qing Ge ◽  
Li Zhao ◽  
Chen Liu ◽  
Xiaoming Ren ◽  
Yi-hui Yu ◽  
...  
Keyword(s):  
Cardiac Hypertrophy ◽  
Protein Expression ◽  
Lymphatic System ◽  
Lymphatic Vessels ◽  
Mouse Heart ◽  
Transverse Aortic Constriction ◽  
Aortic Constriction ◽  
Expression Levels ◽  
Factor C ◽  
Proinflammatory Factors

Cardiac hypertrophy and ventricular remodeling following heart failure are important causes of high mortality in heart disease patients. The cardiac lymphatic system has been associated with limited research, but it plays an important role in the improvement of myocardial edema and the promotion of fluid balance. LCZ696 is a novel combination of angiotensin and neprilysin inhibitors. Here, we studied the role played by LCZ696 during transverse aortic constriction (TAC) induced cardiac hypertrophy and changes in the lymphatic system. Mice undergoing aortic coarctation were constructed to represent a cardiac hypertrophy model and then divided into random groups that either received treatment with LCZ696 (60 mg/kg/d) or no treatment. Cardiac ultrasonography was used to detect cardiac function, and hematoxylin and eosin (H&E) and Masson staining were used to detect myocardial hypertrophy and fibrosis. The proinflammatory factors interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α (TNF-α) were detected in the blood and heart tissues of mice. The protein expression levels of lymphatic-specific markers, such as vascular endothelial growth factor C (VEGF-C), VEGF receptor 3 (VEGFR3), and lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1) were detected in mouse heart tissues. We also examined the colocalization of lymphatic vessels and macrophages by immunofluorescence. The results showed that LCZ696 significantly improved heart dysfunction, cardiac hypertrophy, and fibrosis and inhibited the expression of proinflammatory factors IL-6, IL-1β, and TNF-α in the circulating blood and heart tissues of mice. LCZ696 also decreased the protein expression levels of VEGF-C, VEGFR3, and LYVE-1 in mouse heart tissues, ameliorated the transport load of lymphatic vessels to macrophages, and improved the remodeling of the lymphatic system in the hypertrophic cardiomyopathy model induced by TAC.

Importance of vagal afferents in determining ventilation in newborn rats

1988 ◽  
Vol 65 (3) ◽  
pp. 1033-1039 ◽  
Author(s):  
L. Fedorko ◽  
E. N. Kelly ◽  
S. J. England
Keyword(s):  
Afferent Input ◽  
Vagal Afferents ◽  
Newborn Rats ◽  
Inspiratory Time ◽  
Adult Rats ◽  
Peripheral Chemoreceptor ◽  
Air Breathing ◽  
Ventilatory Pattern ◽  
Threefold Increase ◽  
Bilateral Vagotomy

We studied the effect of acute bilateral vagotomy on ventilation and ventilatory pattern in rats. In 1- to 6-day-old unanesthetized rats, vagotomy resulted in a substantial decrease (38%) in ventilation during air breathing. After vagotomy there was a threefold increase in tidal volume (VT), inspiratory time (TI) doubled, and expiratory time (TE) was six times longer. When studied under isoflurane anesthesia, newborn rats showed decreases in ventilation similar to that observed without anesthesia, whereas anesthetized adult rats had no consistent changes in ventilation. Adult and newborn rats had nearly identical proportionate increases in VT and TI after vagotomy, but TE lengthened to a greater extent in the newborns. Additionally, we demonstrated a significant decrease in ventilation when 100% O2 rather than air was supplied to nonvagotomized unanesthetized newborn rats. Ventilation decreased by 19% after vagotomy under hyperoxic conditions. We conclude that vagal afferent input, probably of pulmonary mechanoreceptor origin, provides positive feedback to respiration in newborn rats and that newborn rats greater than 24 h old also have a degree of peripheral chemoreceptor drive during air breathing.

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