AbstractSensory receptors control nematocyst discharge on sea anemone tentacles. Micromolar -acetylated sugars (, -acetyl neuraminic acid [NANA]) bind chemoreceptors on ectodermal supporting cells and predispose adjacent nematocyst discharge in response to mechanical contact a cyclic adenosine monophosphate (cAMP)-dependent sensitization pathway, while higher NANA levels dose-dependently desensitize. Recent evidence implicates L-type calcium channels in desensitizing the pathway in aconitate sea anemones (also known as ).
View Article and Find Full Text PDFPrevious investigations have shown that REM sleep deprivation impairs the hippocampus-dependent memory, long-term potentiation and causing mood changes. The aim of the present study was to explore the effects of exenatide on memory performance, anxiety- and depression like behavior, oxidative stress markers, and synaptic protein levels in REM sleep deprived rats. A total of 40 male Wistar rats were randomly divided to control, exenatide-treated control, sleep deprivation (SD), wide platform (WP) and exenatide-treated SD groups.
View Article and Find Full Text PDFSeveral studies have shown that low estrogen levels can lead to an increase in the incidence of depression and anxiety during menopause. The hippocampus and prefrontal cortex are parts of the brain involved in depressive- and anxiety-like behaviors. Recent studies have revealed that metformin has neuroprotective effects mainly due to its antioxidant properties.
View Article and Find Full Text PDFDiabetes is associated with depression and anxiety symptoms. The current investigation was designed to explore the effect of melatonin on depressive and anxiety like-behaviours, oxidative stress, levels of AGE, RAGE and S100B in streptozotocin-induced diabetic rats. The animals were divided into four groups: Normoglycemic; Normoglycemic + melatonin; diabetic; diabetic + melatonin (10 mg/kg, for 4 weeks).
View Article and Find Full Text PDFBackground: One of the important risk factors for dementia is chronic cerebral hypoperfusion (CCH) especially in patients with cerebrovascular disease.
Objectives: In the present study, using rat model of bilateral common carotid artery occlusion, the possible protective effects of ethyl pyruvate (EP) have been explored in terms of memory impairment, oxidative stress, and levels of caspase-3, Na-K ATPase, and IL- 1β.
Methods: Rats were treated with EP (50 mg/kg, i.
Background: Intestinal ischemia and reperfusion (I/R) induces oxidative stress, inflammatory response, and acute lung injury. S-nitrosoglutathione (GSNO), a nitric oxide donor, has been documented to have protective effects on experimental ischemia models.
Aim: The aim of this study was to examine the effect of GSNO on I/R-induced intestine and lung damage and detect the potential mechanisms emphasizing the protective role of GSNO.
Aims: Oxidative stress and inflammatory response are major factors causing several tissue injuries in intestinal ischemia and reperfusion (I/R). Agmatine has been reported to attenuate I/R injury of various organs. The present study aims to analyze the possible protective effects of agmatine on intestinal I/R injury in rats.
View Article and Find Full Text PDFPurpose: Multiple organ failure, including acute lung injury, is a common complication of intestinal ischemia and reperfusion (I/R) injury and contributes to its high mortality rate. Activated polymorphonuclear neutrophils and reactive oxygen species contribute to the lung injury caused by intestinal I/R. Mineralocorticoid receptor antagonist spironolactone has a protective effect against I/R injury in animal models of retina, kidney, heart, and brain.
View Article and Find Full Text PDFBackground And Objectives: Serious functional and structural alterations of gastrointestinal tract are observed in failure of blood supply, leading to gastrointestinal dismotility. Activation of opioid receptors provides cardioprotective effect against ischemia-reperfusion (I/R) injury. The aim of the present study was to determine whether or not remifentanil could reduce I/R injury of small intestine.
View Article and Find Full Text PDFBackground And Objectives: Serious functional and structural alterations of gastrointestinal tract are observed in failure of blood supply, leading to gastrointestinal dismotility. Activation of opioid receptors provides cardioprotective effect against ischemia-reperfusion (I/R) injury. The aim of the present study was to determine whether or not remifentanil could reduce I/R injury of small intestine.
View Article and Find Full Text PDFObjectives: Resveratrol appears to have neuroprotective potential in various animal models of brain disorders including cerebral ischemia and neurodegenerative diseases. Chronic cerebral hypoperfusion is a well-known pathological condition contributing to the neurodegenerative diseases such as vascular dementia. Purpose of the present study is to evaluate the possible therapeutic potential of resveratrol in a model of vascular dementia of ovariectomized female rats.
View Article and Find Full Text PDFBackground: Spironolactone (Sp), a mineralocorticoid receptor antagonist, protects against the ischemia reperfusion (IR) injury of retina, kidney, heart, and brain. We aimed to investigate the effects of Sp on intestinal IR injury.
Methods: Male Wistar rats were randomly divided into: (1) a sham control group; (2) an IR control group, subjected to 30 min ischemia and 3 h reperfusion; (3) a group treated with Sp (20 mg/kg) for 3 d before the IR; and (4) a sham-operated control group treated with Sp (20 mg/kg).
Oxygen free radicals and lipid peroxidation may play significant roles in the progress of injury induced by chronic cerebral hypoperfusion of the central nervous system. Rosiglitazone, a well known activator of PPARγ, has neuroprotective properties in various animal models of acute central nervous system damage. In the present study, we evaluate the possible impact of rosiglitazone on chronic cerebral hypoperfused-rats in regard to the levels of oxidative stress, reduced glutathione, and hippocampal neuronal damage.
View Article and Find Full Text PDFObjectives: To determine whether angiotensin and endothelin have any role in testicular ischemia reperfusion injury by investigating the effects of the angiotensin converting enzyme inhibitor enalapril, selective non-peptide angiotensin-II type I blocker losartan and dual endothelin receptor blocker bosentan.
Methods: Rats were anesthetized with thiopental sodium (50 mg/kg i.p.
Chronic cerebral hypoperfusion can cause learning and memory impairment and neuronal damage resembling the effects observed in vascular dementia. PPAR-γ agonists were shown to modulate inflammatory response and neuronal death following cerebral ischemia. The present study was designed to evaluate possible neuroprotective effects of rosiglitazone, a PPAR-γ agonist, in rat model of chronic cerebral hypoperfusion.
View Article and Find Full Text PDFBackground: This study investigated whether N-acetyl cysteine induces any favourable effects on cutaneous incisional wound healing in diabetic and nondiabetic mice. The wounds were assessed using detection of vascular endothelial growth factor (VEGF) and inducible nitric oxide synthase (iNOS) expression, and wound-breaking strength (WBS) measurements.
Methods: In total, 48 BALB/c mice were used.
Oxidative stress is believed to contribute to functional and histopathologic disturbances associated with chronic cerebral hypoperfusion (CCH) in rats. Melatonin has protective effects against cerebral ischemia/reperfusion injury. This effect has mainly been attributed to its antioxidant properties.
View Article and Find Full Text PDFAims: Considering the implications that arose from several recent experimental studies using recombinant human erythropoietin in rodents, erythropoietin has been regarded as a pharmacological preconditioning agent. The purpose of the present study was to evaluate whether erythropoietin has a preconditioning effect against ischemia and reperfusion injury in the small intestine of the rat.
Main Methods: Intestinal ischemia was induced in male Wistar rats by clamping the superior mesenteric artery for 30 min, followed by reperfusion for 180 min.
Neuroprotective effects of estrogens and progesterone have been widely studied in various experimental models. The present study was designed to compare possible neuroprotective effects of 17alpha-estradiol, 17beta-estradiol, and progesterone on oxidative stress in rats subjected to global cerebral ischemia. Global cerebral ischemia was induced in ovariectomized female rats by four vessel occlusion for 10 min.
View Article and Find Full Text PDFJ Pediatr Gastroenterol Nutr
January 2008
Objectives: Studies have shown that nitric oxide (NO) may play a major role in sustaining mucosal integrity; however, NO has been also implicated in the pathogenesis of ischemia/reperfusion (I/R)-related tissue injury. We investigated the effects of L-arginine and NG-nitro L-arginine methyl ester (L-NAME) on the acetylcholine-induced contractile response of ileum and the levels of malondialdehyde (MDA) and reduced glutathione (GSH). Histopathological changes were also evaluated in ileal preparations.
View Article and Find Full Text PDFOne of common pathophysiological states associated with central nervous system is chronic cerebral hypoperfusion (CH) that frequently occurs in conditions such as vascular dementia and Alzheimer's disease. Long term blockage of angiotensin II type 1 (AT(1)) receptor provides protection from ischemia induced injury of brain as well as reduction of cerebrovascular inflammation. Examining effect of the blockage on reduced glutathione (GSH), ascorbic acid (AA), and lipid peroxidation were of purpose in the present study.
View Article and Find Full Text PDFGrowing number of studies implicate that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, or statins, have beneficial effects on ischemia/reperfusion injury that are unrelated to their cholesterol-lowering action. In the present study, we aimed to evaluate possible effects of atorvastatin on oxidative stress, neutrophil accumulation, and contractile response of terminal ileum segments in rats subjected to intestinal ischemia/reperfusion. Intestinal ischemia/reperfusion model was generated by clamping the superior mesenteric artery for 30 min followed by reperfusion for 3 h.
View Article and Find Full Text PDFAim: To examine the effects of adenosine and A1 receptor activation on reperfusion-induced small intestinal injury.
Methods: Rats were randomized into groups with sham operation, ischemia and reperfusion, and systemic treatments with either adenosine or 2-chloro-N(6)-cyclopentyladenosine, A1 receptor agonist or 8-cyclopentyl-1,3-dipropylxanthine, A1 receptor antagonist, plus adenosine before ischemia. Following reperfusion, contractions of ileum segments in response to KCl, carbachol and substance P were recorded.
Erythropoietin exerts hematopoietic effects by stimulating proliferation of early erythroid precursors. Nonhematopoietic effects of erythropoietin have also been shown. It may act as a new angiogenic factor in wound healing.
View Article and Find Full Text PDFOne parameter which might provide an insight into the underlying mechanism of the effect of formaldehyde (FA) inhalation on testicular tissue, is the assessment of heat shock protein 70 (Hsp70), which increases promptly in cells exposed to stress caused by chemical toxicity. Thus, following subchronic exposure at cytotoxic concentrations, we studied the immunohistochemical effect of FA inhalation on changes in Hsp70 content in testicular tissue. We used 18 albino Wistar rats divided into three groups, exposed to 0 (control), 5 and 10 ppm FA gas for a total of 91 days, 8 h/day, five days a week.
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