Antihypertensive Effect ofSyzygium cuminiin Spontaneously Hypertensive Rats

This study evaluated thein vivopotential antihypertensive effect of hydroalcoholic extract ofSyzygium cuminileaves (HESC) in normotensive Wistar rats and in spontaneously hypertensive rats (SHR), as well as itsin vitroeffect on the vascular reactivity of resistance arteries. The hypotensive effect caused by intravenous infusion of HESC (0.01–4.0 mg/kg) in anesthetized Wistar rats was dose-dependent and was partially inhibited by pretreatment with atropine sulfate. SHR received HESC (0.5 g/kg/day), orally, for 8 weeks and mean arterial pressure, heart rate, and vascular reactivity were evaluated. Daily oral administration of HESC resulted in a time-dependent blood pressure reduction in SHR, with a maximum reduction of 62%. In the endothelium-deprived superior mesenteric arteries rings the treatment with HESC reduced by 40% the maximum effect (Emax⁡) of contraction induced by NE. The contractile response to calcium and NE of endothelium-deprived mesenteric rings isolated from untreated SHR was reduced in a concentration-dependent manner by HESC (0.1, 0.25, and 0.5 mg/mL). This study demonstrated thatSyzygium cuminireduces the blood pressure and heart rate of SHR and that this antihypertensive effect is probably due to the inhibition of arterial tone and extracellular calcium influx.

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Blood pressure reducing effects of Phalaris canariensis in normotensive and spontaneously hypertensive rats

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y11-120 ◽

2012 ◽

Vol 90 (2) ◽

pp. 201-208 ◽

Cited By ~ 6

Author(s):

Clévia Santos Passos ◽

Lucimeire Nova Carvalho ◽

Roberto Braz Pontes ◽

Ruy Ribeiro Campos ◽

Olinda Ikuta ◽

...

Keyword(s):

Blood Pressure ◽

Antihypertensive Agent ◽

Spontaneously Hypertensive Rats ◽

Wistar Rats ◽

Antihypertensive Effect ◽

Treatment Interruption ◽

Hypertensive Rats ◽

Spontaneously Hypertensive ◽

Baseline Levels ◽

Phalaris Canariensis

The birdseed Phalaris canariensis (Pc) is popularly used as an antihypertensive agent. The aqueous extract of Pc (AEPc) was administered in adult normotensive Wistar rats and spontaneously hypertensive rats (SHR) and in prehypertensive young SHR (SHRY, 3 weeks old). Animals received AEPc (400 mg·kg–1·day–1, by gavage) for 30 days, then groups were divided into 2 subgroups: one was treated for another 30 days and the other received water instead of AEPc for 30 days. AEPc reduced systolic blood pressure (SBP) in both adult groups; however, treatment interruption was followed by a gradual return of the SBP to baseline levels. SHRY became hypertensive 30 days after weaning. AEPc minimized the increase in SBP in SHRY, but blood pressure rose to levels similar to those in the untreated group with treatment interruption. There were no changes in renal function, diuresis, or Na+ excretion. Pc is rich in tryptophan, and the inhibition of the metabolism of tryptophan to kynurenine, a potential vasodilator factor, prevented the blood pressure reducing effect of AEPc. Moreover, AEPc significantly reduced sympathoexcitation. Data indicate that the metabolic derivative of tryptophan, kinurenine, may be a mediator of the volume-independent antihypertensive effect of Pc, which was at least in part mediated by suppression of the sympathetic tonus.

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Attenuation of the increase in blood pressure and vascular reactivity by chronic oral administration of soft-shelled turtle powder in spontaneously hypertensive rats

Phytotherapy Research ◽

10.1002/ptr.2650040205 ◽

1990 ◽

Vol 4 (2) ◽

pp. 57-61 ◽

Cited By ~ 4

Author(s):

Hong Feng ◽

Norio Matsuki ◽

Hiroshi Saito

Keyword(s):

Blood Pressure ◽

Oral Administration ◽

Spontaneously Hypertensive Rats ◽

Vascular Reactivity ◽

Hypertensive Rats ◽

Spontaneously Hypertensive

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Sodium Lactate Elicits a Rapid Increase in Blood Pressure in Wistar Rats and Spontaneously Hypertensive Rats Effect of Pretreatment with the Antipanic Drugs Clomipramine and Alprazolam

Neuropsychopharmacology ◽

10.1016/0893-133x(94)00082-b ◽

1995 ◽

Vol 12 (3) ◽

pp. 245-250 ◽

Cited By ~ 7

Author(s):

I Wikander

Keyword(s):

Blood Pressure ◽

Spontaneously Hypertensive Rats ◽

Wistar Rats ◽

Sodium Lactate ◽

Hypertensive Rats ◽

Spontaneously Hypertensive

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Regression of myocardial hypertrophy and influence of adrenergic system

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1983.244.1.h97 ◽

1983 ◽

Vol 244 (1) ◽

pp. H97-H101 ◽

Cited By ~ 4

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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