Study of in vivo and in vitro resting vasodilator nitric oxide tone in normotensive and genetically hypertensive rats

Several indirect evidences of alterations in the central catecholaminergic structures were obtained in genetically hypertensive rats. Because they could be of pathogenetic value, we measured, in the present work, the in vivo turnover (TO) of norepinephrine (NE) in brain areas of 5- and 22-wk-old genetically hypertensive (LH) rats of the Lyon strain, and their simultaneously selected normotensive (LN) and low blood pressure (LL) controls. Among the changes observed, the increased TO of NE in the A2 and A6 regions of 5-wk-old LH rats and its decrease in the posteroventral hypothalamic nucleus of 22-wk-old LH animals appeared likely to compensate for hypertension. On the contrary, the decreased TO of NE in the anterior hypothalamic nucleus observed at 5 wk and in the A6 and A1 areas at 22 wk of age in LH rats could participate in the development or the maintenance of hypertension. Above all, it was postulated that the increased TO of NE found in the A7 region of 5-wk-old LH rats could play a primary role in the pathogenesis of hypertension in the Lyon model.

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Cardiovascular Effects Of Chronic Nitric Oxide Synthase Inhibition In Genetically Hypertensive Rats

Clinical and Experimental Pharmacology and Physiology ◽

10.1046/j.1440-1681.2000.03279.x ◽

2000 ◽

Vol 27 (7) ◽

pp. 488-493 ◽

Cited By ~ 7

Author(s):

Stefan J Orange ◽

Janet M Ledingham ◽

Richard Laverty

Keyword(s):

Nitric Oxide ◽

Nitric Oxide Synthase ◽

Cardiovascular Effects ◽

Hypertensive Rats ◽

Genetically Hypertensive Rats ◽

Oxide Synthase ◽

Genetically Hypertensive

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Rate of tryptophan hydroxylation in vivo in brain nuclei of genetically hypertensive rats of the Lyon strain

Cellular and Molecular Life Sciences ◽

10.1007/bf01966156 ◽

1985 ◽

Vol 41 (4) ◽

pp. 478-479 ◽

Cited By ~ 2

Author(s):

L. Denoroy ◽

M. L. Tappaz ◽

R. Fety ◽

M. Vincent ◽

B. Renaud ◽

...

Keyword(s):

Hypertensive Rats ◽

Brain Nuclei ◽

Genetically Hypertensive Rats ◽

Tryptophan Hydroxylation ◽

Genetically Hypertensive

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Vasorelaxant and Antihypertensive Effects of Neferine in Rats: An In Vitro and In Vivo Study

Planta Medica ◽

10.1055/a-1123-7852 ◽

2020 ◽

Vol 86 (07) ◽

pp. 496-504 ◽

Cited By ~ 1

Author(s):

Piyawadee Wicha ◽

Amnart Onsa-ard ◽

Waraluck Chaichompoo ◽

Apichart Suksamrarn ◽

Chainarong Tocharus

Keyword(s):

Nitric Oxide ◽

Thoracic Aorta ◽

Antihypertensive Effect ◽

Soluble Guanylyl Cyclase ◽

K Channel ◽

Channel Blockers ◽

Organ Bath ◽

Hypertensive Rats

AbstractThe present study was performed to examine the antihypertensive effect of neferine in hypertensive rats and its relaxant mechanisms in isolated rat thoracic aorta. The antihypertensive effect was evaluated by tail-cuff methods on NG-nitro-L-arginine methyl ester (L-NAME) (40 mg/kg BW) 4-week hypertensive-induced hypertensive rats. The vasorelaxant effect and its mechanisms were studied by the organ bath technique in the thoracic aorta isolated from normotensive rats. The results indicated that the treatment of neferine (1 mg/kg and 10 mg/kg) markedly decreased the systolic blood pressure (SBP) when compared with the hypertension group (137.75 ± 10.14 mmHg and 132.23 ± 9.5 mmHg, respectively, p < 0.001), without affecting the heart rate. Moreover, neferine (10−12 − 10−4 M) exhibited concentration-dependent vasorelaxation in endothelium-intact rings (Emax values = 98.95 ± 0.66% and pD2 = 7.93 ± 0.28) and endothelium-denuded rings (Emax values = 90.61 ± 1.91% and pD2 = 6.85 ± 0.36). The effects of neferine were reduced by pre-incubation with L-NAME and 1H-[1,2,4]oxadiazolo[4,3-a] quinoxalin-1-one (ODQ) but not with pre-incubation with indomethacin and K+channel blockers. Neferine attenuated the contractions induced by phenylephrine and caffeine in a Ca2+-free solution and also inhibited in CaCl2- and phenylephrine-induced contracted rings. Our study suggests that neferine exhibited hypertensive potential, induced vasorelaxation through the endothelium nitric oxide synthase (eNOS)/nitric oxide (NO)/soluble guanylyl cyclase (sGC) pathway and involved the modulation of Ca2+ influx through Ca2+ channels and intracellular Ca2+ release from the sarcoplasmic reticulum.

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Radical Scavenger Capacity of Jabuticaba Fruit (Myrciaria cauliflora) and Its Biological Effects in Hypertensive Rats

Oxidative Medicine and Cellular Longevity ◽

10.1155/2017/2383157 ◽

2017 ◽

Vol 2017 ◽

pp. 1-10 ◽

Cited By ~ 7

Author(s):

Camila Gabriela de Souza ◽

Daniela Medeiros Lobo de Andrade ◽

Juliana Bahia Reis Jordão ◽

Renato Ivan de Ávila ◽

Leonardo Luiz Borges ◽

...

Keyword(s):

Nitric Oxide ◽

High Efficiency ◽

Biological Effects ◽

Radical Scavenging ◽

Differential Pulse ◽

Radical Scavenger ◽

Hydroxyl Groups ◽

Hypertensive Rats

Jabuticaba is an exotic fruit native to Brazil that has been arousing medicinal interest. Using chemical (HPLC-PDA, resonance mass spectra, and NMR), electroanalytical (differential pulse voltammetry, radical scavenging assay), and pharmacological (in vivo and in vitro) approaches, we have identified its bioactive compounds and hypotensive effects on hypertensive rats. The hydroalcoholic extract of jabuticaba (HEJ) presents a great quantity of phenolic compounds, and several molecules with hydroxyl groups present high efficiency as an antioxidant. The treatment with HEJ (100 and 300 mg/kg/day, for four weeks) presented hypotensive effects on L-NAME-induced hypertensive rats, possibly improving the nitric oxide bioavailability because of its high antioxidant potential. Furthermore, renal and cardiac hypertrophies were also attenuated after the HEJ treatment. Moreover, the vascular responses to contractile and dilating agonists were improved with the HEJ treatment, which is also able to induce nitric oxide production in endothelial cells.

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NE turnover in genetically hypertensive rats of Lyon strain. II. Peripheral organs

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1988.255.4.h736 ◽

1988 ◽

Vol 255 (4) ◽

pp. H736-H741

Author(s):

M. Sautel ◽

J. Sacquet ◽

M. Vincent ◽

J. Sassard

Keyword(s):

Blood Pressure ◽

Kidney Cortex ◽

Cardiac Innervation ◽

Hypertensive Rats ◽

Genetically Hypertensive Rats ◽

Low Blood Pressure ◽

Cervical Ganglia ◽

Peripheral Sympathetic Nervous System ◽

Genetically Hypertensive

The peripheral sympathetic nervous system (SNS) is a major determinant of blood pressure and is likely to be involved in the pathophysiology of hypertension. Because SNS activity varies among organs, we measured the in vivo turnover (TO) of norepinephrine (NE) in seven organs of 5- and 22-wk-old genetically hypertensive (LH), normotensive (LN), and low blood pressure (LL) rats of the Lyon strains. The TO of NE was found normal in the superior cervical ganglia and decreased in the heart of 5-wk-old LH rats compared with both LL and LN controls. This suggests that sympathetic cardiac innervation may not be involved in the development of hypertension. On the contrary, an increased TO of NE in the kidney cortex and an elevated TO of dopamine associated with an increased epinephrine content in the adrenal medulla were observed in 5-wk-old LH rats, which could participate in the development of hypertension in the Lyon model.

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Antihypertensive effects of fargesin in vitro and in vivo via attenuating oxidative stress and promoting nitric oxide release

Canadian Journal of Physiology and Pharmacology ◽

10.1139/cjpp-2015-0615 ◽

2016 ◽

Vol 94 (8) ◽

pp. 900-906 ◽

Cited By ~ 6

Author(s):

Sha Sha ◽

Dandan Xu ◽

Yanwei Wang ◽

Weifang Zhao ◽

Xiaoni Li

Keyword(s):

Oxidative Stress ◽

Nitric Oxide ◽

Antihypertensive Effect ◽

Experimental Period ◽

Biological Information ◽

Ang Ii ◽

Hypertensive Rats ◽

Antioxidant Defence System

Fargesin, a bioactive neolignan isolated from magnolia plants, is widely used in the treatment of managing rhinitis, inflammation, histamine, sinusitis, and headache. To provide more biological information about fargesin, we investigated the effects of fargesin on rat aortic rings and 2-kidney, 1-clip (2K1C) hypertensive rats. In vitro, fargesin caused concentration-dependent vasorelaxation in rat isolated aortic rings induced by KCl and norepinephrine. The effect was weakened by endothelium denudation and nitric oxide (NO) synthesis inhibition. In vivo, the evolution of systolic blood pressure (SBP) was followed by weekly measurements. Angiotensin II (Ang II) and endothelin (ET) levels, NO and nitric oxide synthase (NOS), and plasma and liver oxidative stress markers were determined at the end of the experimental period. After 5 weeks of fargesin treatment, we found that fargesin treatment reduced SBP, cardiac hypertrophy, and Ang II and ET levels of hypertensive rats. Increased NOS activity and NO level were observed in fargesin-treated rats. Normalisation of plasma MDA concentrations and improvement of the antioxidant defence system in plasma and liver accompanied the antihypertensive effect of fargesin. Taken together, these results provided substantial evidences that fargesin has antihypertensive effect in 2K1C hypertensive rats via inhibiting oxidative stress and promoting NO release.

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