جستجوی مقالات مرتبط با کلیدواژه « آنژیوتانسین ii » در نشریات گروه « پزشکی »

One of the important and effective physiological systems in the pathogenesis of type 2 diabetes is the local renin-angiotensin system. The aim of the current study was to determine the effect of aerobic exercise on the function of the local renin-angiotensin system and the gluconeogenesis pathway in the liver tissue of type 2 diabetic rats.

In this experimental study, 18 rats were fed a high-fat diet (HFD) for 8 weeks, and then they developed type 2 diabetes by injecting a single dose of streptozotocin and HFD for four weeks. After the induction of type 2 diabetes, the rats were randomly divided into two groups: 1. diabetes-non-exercise group, 2. diabetes-exercise group. Rats in the exercise group trained 5 days/week, 45 minutes/session for 8 weeks on a treadmill with a mean speed of 20 meters per minute. Blood was collected from rats and liver tissue was extracted and frozen in liquid nitrogen to check the expression of angiotensin II, phosphoenolpyruvate carboxykinase (PEPCK), At1 receptor and Mass receptor genes.

Results of the present study showed that HFD consumption and streptozotocin injection increased blood glucose in rats (P=0.001). The ANOVA test showed that eight weeks of aerobic training caused a significant decrease in the expression of angiotensin II (P=0.001), PEPCK (P=0.003), At1 receptor (P=0.001) genes and the amount of blood glucose (P=0.002) in diabetes-exercise rats compared to diabetes-non-exercise group. Moreover, aerobic training led to a significant increase in the expression of Mass receptor (P=0.001) in diabetes-exercise rats compared to diabetes-non-exercise group.

Eight weeks of aerobic exercise can improve insulin sensitivity and type 2 diabetes by reducing angiotensin II, At1 receptor gene expression, inhibiting hepatic gluconeogenesis and increasing Mass receptor activity.

Aim: Zinc oxide nanoparticles are known as important metal oxide nanoparticles and are used in many medical and biological fields, but concerns are rising due to their potential effects on some organs. The aim of this study was to investigate the effect of aerobic exercise on renal angiotensin-II and angiotensin type 1 receptor levels in administered Rats with Nano Zinc Oxide.
In this experimental research, 35 male Wistar rats were randomly divided into control, salin, nano zinc oxide, exercise and exercise plus nano zinc oxide groups. Zinc nitric oxide (1mg/kg) was injected intraperitoneally, 5 days a week into exercise and exercise plus nano zinc oxide groups. The exercise program consisted of progressive running on a treadmill (5 sessions per week for 4 weeks). Two days after the last application, the rats were euthanized. The kidney tissue is separated and angiotensin-II and angiotensin type 1 receptor were measured. Data were analyzed by SPSS 20 software using one-way ANOVA and Tukey’s post hoc test.
Findings: After 4 weeks of chronic treatment with nano zinc oxide, the levels of angiotensin-II and angiotensin type 1 were significantly increased. Exercise significantly reduced renal angiotensin II and angiotensin type 1 levels. However, these variable levels in exercise plus nano zinc oxide group still were significantly higher than control group (p Aerobic exercise reduces renal angiotensin II and angiotensin type 1 levels in Administered Rats with nano zinc oxide.

The renal sympathetic nerve activity (RSNA) is enhanced in renal failure. Paraventricular nucleus in hypothalamus is an important central site to regulate sympathetic activity. There are angiotensin II (Ang) II receptors in this nucleus. The aim of this study was to evaluate the effects of angiotensin II in hypothalamic paraventricular nucleus (PVN) on renal ischemia-reperfusion injury and RSNA. One week before the induction of renal ischemia-reperfusion (IR) in Sprague-Dawley rats، a cannula was inserted into the right PVN for microinjection of different doses of Ang II (3، 30، and 300 ng). Then right nephrectomy was done. After one week recovery، renal IR injury was induced by clamping the left renal artery for 45 minute and then reperfusion for 3 or 24 hour. Ten minutes before the induction of renal ischemia-reperfusion، administration of different doses of angiotensin II were done in different groups. In all animals، left renal sympathetic activity was recorded before and during renal ischemia. After 3 or 24 hours reperfusion the blood، kidney and brain were collected to assay renal function and histology and oxidative stress indices Superoxide Dismutase، SOD and Malondialdehyde، MDA) in PVN. Administration of different pharmacological doses of angiotensin II into PVN exaggerated the renal IR injury. Angiotensin II in different doses increased the plasma creatinine and BUN levels and renal histological markers in comparison to renal IR injury (P<0. 05). Angiotensin II had detrimental effects on RSNA and oxidative stress indices Super Oxide Dismutase (SOD) and Malondialdehyde (MDA) in PVN as the dose was increased (P<0. 05). These data showed that the PVN is a responsive site for central Ang II-induced damage in renal IR injury. We suggested the central effects of Ang II in the PVN on renal IR injury are mediated by oxidative stress in the PVN، and the peripheral effects by a sympathetic pathway.

Several reports indicated the role of angiotensin II antagonists in suppression of different tumvors. Some of the recent studies point to the increasing effect of angiotensin II on expression of important factors regarding to the tumor growth. Also the role of integrins in growth and metastasis of tumoral cells is very important but the role of angiotensin II in the expression of integrins is not clear yet.

Melanoma tumors were induced in C57 mice using S. C. injections of B16-F10 cells. Losartan was I. P. injected to C57 mice. Also B16-F10 cells were cultured and incubated with angiotensin II with or without losartan for two hours and the expression of α3، αv and b3 integrins were studied using western blotting.

Our results indicate the suppressing role of losartan on tumor growth (day17، P=0. 013; day18: P=0. 0015). In addition angiotensin II increased significantly the expression of studied integrins in B16-F10 cultured cells (integrin αV: P=0. 049; Integrin α3: P= 0. 016; integrin β3: P= 0. 037)، and losartan completely abolished this effect.

The role of angiotensin II in tumor growth may be because of reasons including its role in elevating the expression levels of α3، αv and 3 integrins. In animal model of melanoma، losartan suppressed the tumor growth through AT1 receptors inhibition. The present study indicates the importance of the drugs such as losartan besides the standard therapeutic approach for tumors

Locus coeruleus is one of important involved sites in morphine withdrawal signs, contains high densities of Angiotensin II receptor binding sites. In this study the effect of microinjection of Angiotensin II and captopril to the Locus coeruleus on morphine withdrawal signs was evaluated. Male wistar rats were anesthetized and stainless style cannula implanted in the locus coeruleus and allowed to recover from surgery. Morphine was injected 3 times in each day for 4 days to induce morphine dependence. The animals divided into 3 groups; control group received saline and case groups received Angiotensin II (1 nanomole) or captopril (30 µg) before naloxone injection. After naloxone injection, morphine withdrawal signs were assessed and compared between groups. In Angiotensin group, some of withdrawal signs such as wet dog shakes was significantly higher than saline group (P < 0.05). Expression of some of withdrawal signs such as jumping in Angiotensin group was decreased more than saline group (P < 0.01). Also, in captopril group some of withdrawal signs such as wet dog shakes was significantly higher than those of saline group (P < 0.05. Expression of some of withdrawal signs such as writhing posture, teeth chattering, grooming, genital grooming and head shakes were decreased in captopril group more than saline group (P < 0.05). We suggest that Angiotensin II have some roles in opioid withdrawal through locus coeruleus nucleous which contains considerable receptors for it.