scholarly journals Lisinopril Indifferently Improves Heart Rate Variability During Day and Night Periods in Spontaneously Hypertensive Rats

2013 ◽  
pp. 237-245 ◽  
Author(s):  
S. ALBARWANI ◽  
S. AL-SIYABI ◽  
M. O. TANIRA
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Heart Rate Variability ◽  
Spontaneously Hypertensive Rats ◽  
Radio Telemetry ◽  
Tap Water ◽  
Fold Increase ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive ◽  
Arterial Blood

The aim of this work was to investigate the effect of 10 weeks of lisinopril treatment to spontaneously hypertensive rats (SHRs) on day/night variations of blood pressure, heart rate and autonomic cardio-regulation parameters. Male SHR with surgically implanted radio-telemetry implant that provided direct measurements of arterial pressure and electrocardiogram wave were used. Animals were allocated to two groups (n=5 each). The first group was treated with lisinopril (20 mg/kg by gavage) daily for 10 weeks (treated group); whereas the second was gavaged daily with tap water (untreated group). Arterial blood pressure, ECG and other telemetry parameters were recorded at the start and at the end of 10-week treatment. Collected data were analyzed using specialized software and were statistically tested. In addition to the expected lowering of blood pressure, spectral analysis of R-R intervals revealed that lisinopril treatment for 10 weeks significantly caused 2-3 fold increase in heart rate variability (HRV) during both active and inactive periods. However, R-R interval durations demonstrated variable distribution patterns during those periods. The cause of observed distribution pattern of R-R intervals during active and inactive periods may be of significance to better understand HRV changes and warrants further investigations.

scholarly journals Hypotensive and Bradycardic Effects of Quinovic Acid Glycosides from Aspidosperma fendleri in Spontaneously Hypertensive Rats

2015 ◽  
Vol 10 (2) ◽  
pp. 1934578X1501000 ◽  
Author(s):  
Omar Estrada ◽  
Juan M. González-Guzmán ◽  
María M. Salazar-Bookman ◽  
Alfonso Cardozo ◽  
Eva Lucena ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Arterial Blood Pressure ◽  
Mean Arterial Blood Pressure ◽  
Spontaneously Hypertensive Rats ◽  
Cardiovascular Effects ◽  
Hypertensive Rats ◽  
Triterpenoid Saponins ◽  
Spontaneously Hypertensive ◽  
Arterial Blood

The Aspidosperma genus (Apocynaceae) represents one of the largest sources of indole alkaloids widely associated with cardiovascular effects. Aspidosperma fendleri, a plant found mainly in Venezuela, has a single phytochemical report in which is revealed the presence of alkaloids in its seeds. This study explored the cardiovascular effects of an ethanolic extract of A. fendleri leaves (EEAF) in spontaneously hypertensive rats (SHR) and its potential bioactive compounds. Using bioguided fractionation, fractions and pure compounds were intravenously administered to SHR and their effects on mean arterial blood pressure (MABP) and heart rate (HR) monitored over time. EEAF induced hypotensive and bradycardic effects as shown by significant reductions in mean arterial blood pressure (MABP) and heart rate (HR), respectively. Bioactivity-guided fractionation led to the isolation of a mixture of two known isomeric triterpenoid glycosides identified by spectral evidence as quinovic acid 3- O-β-rhamnopyranoside and quinovic acid 3- O-β-fucopyranoside. This mixture of triterpenoid saponins induced reductions in MABP and HR similar to those induced by propranolol. Together, these findings indicate that the two quinovic acid glycosides are responsible for the hypotensive and bradycardic effects which suggest their potential use in cardiovascular therapy.

scholarly journals Cardiovascular Effects of Fermented Milk Containing Angiotensin-Converting Enzyme Inhibitors Evaluated in Permanently Catheterized, Spontaneously Hypertensive Rats

2002 ◽  
Vol 68 (7) ◽  
pp. 3566-3569 ◽  
Author(s):  
Anders Fuglsang ◽  
Dan Nilsson ◽  
Niels C. B. Nyborg
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Angiotensin Converting Enzyme ◽  
Spontaneously Hypertensive Rats ◽  
Fermented Milk ◽  
Pressure Effects ◽  
Converting Enzyme ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive ◽  
Arterial Blood

ABSTRACT In this study, two strains of Lactobacillus helveticus were used to produce fermented milk rich in angiotensin-converting enzyme (ACE) inhibitors. In vitro tests revealed that the two milks contained competitive inhibitors of ACE in amounts comparable to what has been obtained in previously reported studies. The two milks were administered by gavage to spontaneously hypertensive rats that had had a permanent aortic catheter inserted through the left arteria carotis, and mean arterial blood pressure and heart rate were monitored from 4 to 8 h after administration. Unfermented milk and milk fermented with a lactococcal strain that does not produce inhibitors were used as controls. Highly significant blood pressure effects were observed; i.e., milk fermented with the two strains of L. helveticus gave a more pronounced drop in blood pressure than the controls. Significant differences in heart rate effects were detected with one of the strains.

scholarly journals Hypotensive Effect Induced by Mandibular Extension in Aged, Hypertensive Humans and Rats

2021 ◽  
pp. 1-5
Author(s):  
Cristina Del Seppia ◽  
Cristina Del Seppia ◽  
Giuseppe Federighi ◽  
Enza Fommei ◽  
Sergio Ghione ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Arterial Blood Pressure ◽  
Spontaneously Hypertensive Rats ◽  
Human Subjects ◽  
Mouth Opening ◽  
Hypotensive Effect ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive ◽  
Arterial Blood

Objectives: Previous research has shown that submaximal mouth opening by mandibular extension (ME) is followed by a prolonged reduction in blood pressure. This effect was observed in young and adult normotensive and hypertensive rats and in young normotensive human subjects. Methods: We assessed the effects of a ME for 10 minutes obtained with a fixed mouth opener in both hypertensive adult humans (aged 55 years or older) and elderly (6-7 months) anaesthetized, hypertensive rats (SHR). Blood pressure and heart rate were measured every 10 minutes by non-invasive automatic recorders for 30 minutes before and 120 minutes after the procedure. Nine human hypertensive subjects (7 experimental and 2 controls) and seven spontaneously hypertensive rats (5 experimental and 2 controls) were tested. Results: A statistically significant reduction in systolic blood pressure (SBP), mean arterial blood pressure (MABP) and heart rate (HR) was observed after ME in the seven hypertensive human subjects, in whom an average decrease of 15 mmHg for SBP, 10 mmHg for MABP and 7 bpm for HR, was observed. A similar hypotensive effect was recorded in spontaneously hypertensive rats that displayed a statistically significant decrease of SBP, DBP and MABP, amounting to about 40-50 mmHg. Conclusion: This study provides the first evidence that ME has an important and prolonged hypotensive effect when applied to subjects with high blood pressure, making their arterial blood pressure decrease toward normal values for at least two hours.

Regression of myocardial hypertrophy and influence of adrenergic system

1983 ◽  
Vol 244 (1) ◽  
pp. H97-H101 ◽  
Author(s):  
S. Sen ◽  
R. C. Tarazi
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Regression Analysis ◽  
Arterial Pressure ◽  
Spontaneously Hypertensive Rats ◽  
Myocardial Hypertrophy ◽  
Cardiac Response ◽  
Adrenergic System ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive

Studies of regression of myocardial hypertrophy in spontaneously hypertensive rats (SHR) suggest that the adrenergic system may play an important role in the reversal of hypertrophy. The effect of propranolol on reversal of hypertrophy, however, is still controversial. This study describes the effect of propranolol, given alone or in combination with hydralazine in different ratios for 4 wk, on blood pressure (BP), ventricular weight, and myocardial catecholamine (MC) concentrations. The data show that a certain ratio of propranolol to hydralazine (750:30) leads to moderate BP control (196-156 mmHg) without increased MC (634 vs. 552 ng/g) and moderately reduced hypertrophy. Reduction of BP alone with increased MC (hydralazine alone) or reduction of MC without BP control (propranolol alone) failed to reduce hypertrophy. A significant correlation between both ventricular weight and heart rate with MC (r = 0.6) was obtained by multiple regression analysis. This study suggests that adrenergic factors seem to play an important role in modulating structural cardiac response to variations in arterial pressure.

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