Gastric mucosal damage in water immersion stress:Mechanism and prevention with GHRP-6  

作　　者：Shu Guo Qian Gao Qing Jiao Wei Hao Xue Gao Ji-Min Cao 

机构地区：[1]De- partment of Physiology and Pathophysiology, Institute of Ba- sic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Bei- jing 100005, China [2]Department of Radiology, Taishan Medical College,Tai'an 271016, Shandong Province, China

出　　处：《World Journal of Gastroenterology》2012年第24期3145-3155,共11页世界胃肠病学杂志（英文版）

基　　金：Supported by National Natural Science Foundation of China, No.81071072,No.31171088(to Cao JM) and No.81000060(to Gao X)

摘　　要：AIM:To investigate the mechanism of gastric mucosal demage induced by water immersion restraint stress(WRS) and its prevention by growth hormone releasing peptide-6(GHRP-6).METHODS:Male Wistar rats were subjected to conscious or unconscious(anesthetized) WRS,simple restraint(SR),free swimming(FS),non-water fluid immersion,immersion without water contact,or rats were placed in a cage surrounded by sand.To explore the sensitivity structures that influence the stress reaction besides skin stimuli,a group the rats had their eyes occluded.Cervical bilateral trunk vagotomy or atropine injection was performed in some rats to assess the parasympathetic role in mucosal damage.Gastric mucosal lesions,acid output and heart rate variability were measured.Plasma renin,endothelin-1 and thromboxane B2 and gastric heat shock protein 70 were also assayed.GHRP-6 was injected [intraperitoneal(IP) or intracerebroventricular(ICV)] 2 h before the onset of stress to observe its potential prevention of the mucosal lesion.RESULTS:WRS for 6 h induced serious gastric mucosal lesion [lesion area,WRS 81.8 ± 6.4 mm 2 vs normal control 0.0 ± 0.0 mm 2,P < 0.01],decreased the heart rate,and increased the heart rate variability and gastric acid secretion,suggesting an increase in vagal nervecarrying stimuli.The mucosal injury was inversely correlated with water temperature(lesion area,WRS at 35 ℃ 56.4 ± 5.2 mm 2 vs WRS at 23 ℃ 81.8 ± 6.4 mm 2,P < 0.01) and was consciousness-dependent.The injury could not be prevented by eye occlusion,but could be prevented by avoiding contact of the rat body with the water by dressing it in an impermeable plastic suit.When water was replaced by vegetable oil or liquid paraffin,there were gastric lesions in the same grade of water immersion.When rat were placed in a cage surrounded by sand,there were no gastric lesions.All these data point to a remarkable importance of cutenuous information transmitted to the high neural center that by vagal nerves reaching the gastric mucosa.FS alone also induced serious AIM：To investigate the mechanism of gastric mucosal demage induced by water immersion restraint stress（WRS） and its prevention by growth hormone releasing peptide-6（GHRP-6）.METHODS：Male Wistar rats were subjected to conscious or unconscious（anesthetized） WRS,simple restraint（SR）,free swimming（FS）,non-water fluid immersion,immersion without water contact,or rats were placed in a cage surrounded by sand.To explore the sensitivity structures that influence the stress reaction besides skin stimuli,a group the rats had their eyes occluded.Cervical bilateral trunk vagotomy or atropine injection was performed in some rats to assess the parasympathetic role in mucosal damage.Gastric mucosal lesions,acid output and heart rate variability were measured.Plasma renin,endothelin-1 and thromboxane B2 and gastric heat shock protein 70 were also assayed.GHRP-6 was injected [intraperitoneal（IP） or intracerebroventricular（ICV）] 2 h before the onset of stress to observe its potential prevention of the mucosal lesion.RESULTS：WRS for 6 h induced serious gastric mucosal lesion [lesion area,WRS 81.8 ± 6.4 mm 2 vs normal control 0.0 ± 0.0 mm 2,P 〈 0.01],decreased the heart rate,and increased the heart rate variability and gastric acid secretion,suggesting an increase in vagal nervecarrying stimuli.The mucosal injury was inversely correlated with water temperature（lesion area,WRS at 35 ℃ 56.4 ± 5.2 mm 2 vs WRS at 23 ℃ 81.8 ± 6.4 mm 2,P 〈 0.01） and was consciousness-dependent.The injury could not be prevented by eye occlusion,but could be prevented by avoiding contact of the rat body with the water by dressing it in an impermeable plastic suit.When water was replaced by vegetable oil or liquid paraffin,there were gastric lesions in the same grade of water immersion.When rat were placed in a cage surrounded by sand,there were no gastric lesions.All these data point to a remarkable importance of cutenuous information transmitted to the high neural center that by vagal nerves reaching the gas

关 键 词：Growth substances Gastric ulcer STRESS Be-havior and emotions Autonomic nerve Heart rate vari-ability 

分 类 号：Q64[生物学—生物物理学] TS55[轻工技术与工程—皮革化学与工程]