Journal of gastroenterology · 2008
The role of nuclear factor-kappaB in the effect of angiotensin II in the paraventricular nucleus in protecting the gastric mucosa from ischemia-reperfusion injury in rats.
СтатьяПоддержка исследования: вне правительства СШАНазвание и аннотация: Перевод пока не подготовлен
Обработка статьи · этапы, ошибки и управление
Загрузка состояния…
Ошибки и ограничения
История · было → стало
Состояние обновляется каждые 5 секунд, пока блок открыт. Процент показывается только там, где известен объём работы. Пауза останавливает продолжение этапа; текущий запрос к источнику может завершиться.
Zhang Yong-Mei, Wei Er-Qing, Hu Xia, Qiao Wei-Li, Shi Yue, Xu Ming, Zhang Jian-Fu
Аннотация
BACKGROUND: The purpose of this study was to elucidate the role of nuclear factor kappaB (NF-kappaB) in the development of gastric ischemia-reperfusion (GI-R) injury and in mediating the effects of angiotensin II (Ang II) in the paraventricular nucleus (PVN) on GI-R injury.
METHODS: GI-R injury was induced in rats by clamping the celiac artery for 30 min and then reperfusing for 1 h. A cannula was inserted into the unilateral PVN for microinjection of Ang II. The expressions and levels of NF-kappaB (p65), IkappaB-alpha, and phosphorylated IkappaB-alpha in rat gastric mucosa were examined by Western blotting and immunohistochemistry. A laser Doppler flowmeter was used to assess gastric blood flow (GBF). Malondialdehyde (MDA) was determined using the thiobarbituric acid (TBA) method, and superoxide dismutase (SOD) activity was determined by the xanthine/xanthine oxidase method.
RESULTS: Microinjection of Ang II (3, 30, and 300 ng) into the PVN dose-dependently inhibited GI-R injury. The levels and expressions of NF-kappaB (p65) and phosphospecific IkappaB-alpha protein increased 1 h after GI-R and were markedly reduced by microinjection of Ang II into the PVN. In contrast, the level and expression of IkappaB-alpha protein decreased 1 h after ischemia-reperfusion and recovered to the normal level by microinjection of Ang II into the PVN. The effects of Ang II were prevented by pretreatment with the Ang II AT1 receptor antagonist losartan (5 microg) microinjected into the lateral cerebral ventricle. Inhibition of NF-kappaB activity by pyrrolidine dithiocarbamate (PDTC, 200 mg/kg) produced similar effects in rats subjected to ischemia-reperfusion with or without microinjection of Ang II into the PVN. Administration of PDTC attenuated gastric mucosal injury and suppressed the activation of NF-kappaB (p65). Ang II microinjection into the PVN increased GBF and decreased the MDA content but did not alter SOD activity in the gastric mucosa following ischemia-reperfusion.
CONCLUSIONS: NF-kappaB plays a role in PVN Ang II-mediated protection against GI-R injury. These central effects of Ang II are mediated by AT1 receptors.
METHODS: GI-R injury was induced in rats by clamping the celiac artery for 30 min and then reperfusing for 1 h. A cannula was inserted into the unilateral PVN for microinjection of Ang II. The expressions and levels of NF-kappaB (p65), IkappaB-alpha, and phosphorylated IkappaB-alpha in rat gastric mucosa were examined by Western blotting and immunohistochemistry. A laser Doppler flowmeter was used to assess gastric blood flow (GBF). Malondialdehyde (MDA) was determined using the thiobarbituric acid (TBA) method, and superoxide dismutase (SOD) activity was determined by the xanthine/xanthine oxidase method.
RESULTS: Microinjection of Ang II (3, 30, and 300 ng) into the PVN dose-dependently inhibited GI-R injury. The levels and expressions of NF-kappaB (p65) and phosphospecific IkappaB-alpha protein increased 1 h after GI-R and were markedly reduced by microinjection of Ang II into the PVN. In contrast, the level and expression of IkappaB-alpha protein decreased 1 h after ischemia-reperfusion and recovered to the normal level by microinjection of Ang II into the PVN. The effects of Ang II were prevented by pretreatment with the Ang II AT1 receptor antagonist losartan (5 microg) microinjected into the lateral cerebral ventricle. Inhibition of NF-kappaB activity by pyrrolidine dithiocarbamate (PDTC, 200 mg/kg) produced similar effects in rats subjected to ischemia-reperfusion with or without microinjection of Ang II into the PVN. Administration of PDTC attenuated gastric mucosal injury and suppressed the activation of NF-kappaB (p65). Ang II microinjection into the PVN increased GBF and decreased the MDA content but did not alter SOD activity in the gastric mucosa following ischemia-reperfusion.
CONCLUSIONS: NF-kappaB plays a role in PVN Ang II-mediated protection against GI-R injury. These central effects of Ang II are mediated by AT1 receptors.
Предметные рубрики MeSH
Angiotensin IIAngiotensin II Type 1 Receptor BlockersAnimalsDose-Response Relationship, DrugGastric MucosaI-kappa B ProteinsLosartanMaleMalondialdehydeNF-KappaB Inhibitor alphaNF-kappa BParaventricular Hypothalamic NucleusPhosphorylationPyrrolidinesRatsRats, Sprague-DawleyRegional Blood FlowReperfusion InjurySuperoxide DismutaseThiocarbamates