Acute and chronic stress differently affect visceral sensitivity to rectal distension in female rats
Acute and chronic stress differently affect visceral sensitivity to rectal distension in female rats
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DOI：
10.1046/j.1365-2982.2002.00305.x
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发表时间：
2002-02-01
影响因子：
3.5
通讯作者：
Bueno, L
中科院分区：
文献类型：
--
作者：
Bradesi, S;Eutamene, H;Bueno, L
应激性生活事件经常与肠易激综合征(IBS)的外在症状有关。越来越多的证据表明，急性和慢性应激刺激涉及不同的生理机制和神经内分泌反应，因此，我们研究了急性和慢性应激对雌性大鼠内脏伤害性感受的影响以及结肠肥大细胞参与这一影响。采用腹肌肌电图法观察急性和慢性部分束缚应激(Prs)对直肠扩张(RD)内脏敏感性的影响，通过测定P物质(SP)体外刺激大鼠结肠组织中组胺释放来检测RD大鼠结肠肥大细胞的活性。在所有体积的扩张中，与假手术相比，急性手术显著增强了对RD的腹部反应。相反，与对照组相比，慢性PRS对最大的膨胀量(0.8和1.2毫升)引起过敏性痛觉反应，但不影响最低容量(0.4毫升)的腹部收缩次数。急性和慢性PR均可增加SP诱导的组胺释放，但不影响肥大细胞的数量。急性和慢性PRS大鼠结肠组织中组胺的释放相似，但显著高于假手术组大鼠，急性和慢性PRS对雌性大鼠RD反应的内脏敏感性有不同程度的影响。然而，这种差异不能归因于两种应激模式对肥大细胞组胺释放的不同影响。
Stressful life events are frequently associated with outward signs of irritable bowel syndrome (IBS). Increasing evidence suggests that acute and chronic stress stimuli implicate different physiological mechanisms and neuroendocrine responses, Therefore, we investigated the influence of acute and chronic stress on visceral nociception in female rats and the involvement of colonic mast cells in this effect. The effect of acute and chronic partial restraint stress (PRS) on visceral sensitivity to rectal distension (RD) was assessed by abdominal muscle electromyography, Colonic mast cell activation was determined by measuring histamine release after in vitro stimulation with substance P (SP) in colonic samples from rats experiencing RD vs. controls. Acute PRS significantly enhanced abdominal response to RD compared with sham PRS for all volumes of distension. In contrast, chronic PRS induced a hyperalgesic response for the highest volumes of distension (0.8 and 1.2 mL), but did not affect the number of abdominal contractions for the lowest volume (0.4 mL) compared with controls. Both acute and chronic PRS increased in vitro SP-induced histamine release without affecting mast cell numbers. RD induced similar in vitro histamine release from colonic samples from both acute and chronic PRS rats; this release, however, was significantly higher than that measured in sham-PRS rats, Acute and chronic PRS differently influence visceral sensitivity in response to RD in female rats. This difference, however, cannot be attributed to a different effect of either stress paradigm on mast cell histamine release.