Vasorelaxant effects of the chronic treatment with melatonin on mesenteric artery and aorta of spontaneously hypertensive rats

Girouard, Hélène; Chulak, Chantal; LeJossec, Mireille; Lamontagne, Daniel; Champlain, Jacques de

doi:10.1097/00004872-200108000-00004

Cited by 70 publications

(45 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Preliminary evidence suggests that it may help strengthen the immune system. Reported the development of hypertension in rats after pinealectomy and the reason for this; increased plasma renin activity and the renin-angiotensin-aldosterone system have been implicated (Burgess et al, 2001;Karppanen et al, 1970;Zanoboni et al, 1967;Girouard et al, 2002).…”

Section: Discussionmentioning

confidence: 99%

Effects of the melatonin on the kidney of high fat diet fed obese rats: A stereological and histological approach

Yurt¹,

KAYHAN²,

Altunkaynak³

et al. 2013

jecm

View full text Add to dashboard Cite

Article HistoryReceived 25/ 02 /2012 Accepted 22/ 05 /2013Obesity is associated with multiple conditions that are known to compromise renal function, including hypertension, diabetes, hyperuricemia, and the metabolic syndrome that can independently have a detrimental effect on renal function. The aim of this study was to examine effects of fatty diet induced obesity and melatonin on kidney in female rats by histological and quantative methods. For this aim, 24 rats were randomly divided into 4 groups including Non-obese control (NC group), Obese control (OC group), Nonobese Melatonin (NOM group) and Obese-Melatonin (OM group) groups. In the obese groups, rats, were fed with high fat diet (40% of calories from fat) for 15 weeks. The rats of the non-obese groups were fed with standard, commercial rat diet during the same period. At the end of the 15 th week, rats in the melatonin groups started to received daily injections (i.p.) 10 mg/kg melatonin for 6 weeks. At the end of the experiment, a serial sections of kidneys were stained with Hematoxylen-eosin. Glomerular number (Ng) is considered a major determinant of renal function and outcome. Unbiased stereological methods have been used to estimate of Ng. Also histopathological analysis was made on the same sections. Stereological examination of the kidneys showed differences in terms of total kidney volume, volume of cortex, medulla and numerical density of glomeruli among the groups. Light microscopic investigation showed a dilatation in blood vessels and Bowman's space, mononuclear cell infiltration, degeneration in nephrons, including glomerulosclerosis and tubular defects, and an increase in the connective tissue in the kidneys in the OC group. But, both stereological deficits and histological damages detected in OC group recovered in OM group after melatonin treatment. We suggested that a fatty diet is responsible for the rats' obesity and may lead to renal deformities as a result of histopathological changes such as vessel dilatation, tubular defects, inflammation and connective tissue enlargement of the kidney. Also melatonin treatment after obesity may contribute structural and functional healing.

show abstract

Section: Discussionmentioning

confidence: 99%

Effects of the melatonin on the kidney of high fat diet fed obese rats: A stereological and histological approach

Yurt¹,

KAYHAN²,

Altunkaynak³

et al. 2013

jecm

View full text Add to dashboard Cite

show abstract

“…The present study was aimed at delineating the mechanisms underlying the selective effect of HO-1 inducers on the development of hypertension in young and adult SHR. To this end, the expression and function of the HO/CO-sGC/cGMP system in mesenteric artery beds from SHR and WistarKyoto rats (WKY) at different stages of hypertension were examined, considering the important role of peripheral blood vessels such as the mesenteric artery 19,20 in controlling the peripheral resistance in hypertension.…”

mentioning

confidence: 99%

Selective Regulation of Blood Pressure by Heme Oxygenase-1 in Hypertension

2002

View full text Add to dashboard Cite

Abstract-Heme oxygenase (HO) and carbon monoxide (CO) participate in the homeostatic control of cardiovascular functions, including the regulation of blood pressure (BP). Upregulation of the HO/CO system has been shown to lower BP in young (8 weeks) but not in adult (20 weeks) spontaneously hypertensive rats (SHR). The underlying mechanism for this selective effect, however, has been unknown and was investigated in the present study. Key Words: cyclic GMP Ⅲ hypertension, experimental Ⅲ rats, spontaneously hypertensive Ⅲ mesenteric arteries Ⅲ heme oxygenase T he homeostatic control of biological functions is maintained by a wide array of metabolic pathways capable of triggering the necessary corrective mechanisms to maintain cellular functions within physiological limits. Among these metabolic pathways is the catalytic breakdown of heme by heme oxygenase (HO) to carbon monoxide (CO), bilirubin, and iron. HO is a microsomal enzyme with three distinct isoforms, namely, inducible (HO-1) and constitutive forms (HO-2 and HO-3). 1 HO-1 is a 32-kDa protein that is not constitutively present in cells but expressed after exposure of cells to different stimuli. 2 This enzyme is believed to play a predominant role for CO generation during pathophysiological episodes. HO-2 is a 36-kDa protein that is normally expressed in many organs under physiological conditions. 3 For example, HO-2 expressed in endothelial and smooth muscle layers of blood vessels generates CO that intrinsically modulates vascular tone. 4 HO-3 (33 kDa) shares Ϸ90% homology with HO-2. 1 HO-3 is devoid of catalytic activity and considered important in the regulation of heme proteins. 1 CO has been shown to induce relaxation of vascular smooth muscle cells (VSMC) by stimulating soluble gyanylyl cyclase (sGC), opening calcium-activated K ϩ channels, and acting on cytochrome P450. 5 sGC is a heme-containing heterodimer composed of ␣ and ␤ subunits. ␣ 1 and ␤ 1 of the catalytic domain have molecular weights of 82 kDa and 70 kDa, respectively, whereas the regulatory domain is made up of ␣ 2 and ␤ 2 subunits. The activation of sGC converts GTP to cGMP. Intracellular cGMP regulates biological functions by activating cGMP-dependent protein kinases, directly gating ion channels, 5,6 or regulating phosphodiesterase hydrolysis. The activation of the sGC/cGMP pathway is one of major mechanisms for CO-induced vasorelaxation. The synchronized activities of the HO/CO-sGCc/GMP system may constitute an important metabolic pathway in the modulation of blood pressure (BP).The HO/CO metabolic pathway is believed to be involved in the regulation of basal tone of resistance blood vessels, 7 growth of VSMC, and vascular remodeling. 8 Many recent reports have shown that VSMC constitute a major site for HO-1 induction. 9 Examples include hemin-induced dilation of small arteries of the peritoneum 10 and HO-1 induction in VSMC of human atherosclerotic lesions. 11 Also, CO produced from heme metabolism in blood vessels 12 was reported to elicit relaxation 13 through the elevation of c...

show abstract

“…As reported previously, melatonin decreases plasma renin and serum norepinephrine concentrations (K-Laflamme et al, 1998). The improved NO production and decrease oxidative load after melatonin administration may lead to BP reduction (Girouard et al, 2001).…”

Section: Discussionmentioning

confidence: 72%

Protective Role of Melatonin in L-Name Induced Hypertension in Male Albino Rats

Khdhr

Mahmud

2016

SJUOZ

View full text Add to dashboard Cite

Summary:The objective for the present study is to investigate the effects of melatonin (MEL) on systolic blood pressure (SBP), some biochemical parameters; serum (malondialdehyde (MDA), superoxide dismutase (SOD), reduced glutathione (GSH), nitric oxide (NO)) in NG-nitro-L-arginine methyl ester hydrochloride (L-NAME) treated rats. The male albino rats divided into five groups treated for 4 weeks: Group 1: Control rats. Group 2: L-NAME (35 mg/100 ml drinking water). Group 3: L-NAME (35 mg/100 ml drinking water) + melatonin (30 mg/Kg diet). Group 4: L-NAME (35 mg/100 ml drinking water) + melatonin (60 mg/Kg diet). Group 5: L-NAME (35 mg/100 ml drinking water) + melatonin (120 mg/Kg diet). A significant elevation in SBP and serum MDA were detected in L-NAME treated rats. Coadministration of melatonin with L-NAME prevented increasing in SBP and serum level of MDA in a dose dependent manner. On the other hand serum levels of SOD and GSH were decreased in response to L-NAME treatment, while, co-treatment with melatonin increased SOD and GSH in a dose dependent manner. The decrease serum NO level in response to L-NAME was significantly increased by melatonin but its level was decreased by increasing melatonin doses.In conclusion: L-NAME induced hypertension model was associated with decreased NO level, interestingly; melatonin increased serum NO in L-NAME treatments, but with increasing dose of MEL, NO level was decreased. Furthermore; MEL through its antioxidant properties reduced oxidative stress and prevented lipid peroxidation.

show abstract

Vasorelaxant effects of the chronic treatment with melatonin on mesenteric artery and aorta of spontaneously hypertensive rats

Cited by 70 publications

References 28 publications

Effects of the melatonin on the kidney of high fat diet fed obese rats: A stereological and histological approach

Effects of the melatonin on the kidney of high fat diet fed obese rats: A stereological and histological approach

Selective Regulation of Blood Pressure by Heme Oxygenase-1 in Hypertension

Protective Role of Melatonin in L-Name Induced Hypertension in Male Albino Rats

Contact Info

Product

Resources

About