Nellgård P, Bojö L, Jönsson A, Cassuto J
Department of Anesthesiology and Intensive Care, Sahlgren's Hospital, Göteborg University, Sweden.
Eur J Gastroenterol Hepatol. 1995 Nov;7(11):1059-63.
To investigate the importance of adrenoceptors on fluid losses in small bowel obstruction.
Evaluation of the effects of adrenergic agonists and antagonists on in-vivo net fluid secretion in chronic small bowel obstruction in rats.
Net fluid transport in a jejunal segment was continuously registered in vivo after 18 h of mechanical obstruction of the small bowel in anaesthetized rats. The effect on net fluid transport of adrenoceptor agonists and antagonists and of isotonic saline was quantified.
Clonidine, an alpha 2-agonist, had a significant (P < 0.05) anti-secretory effect, while yohimbine, an alpha 2-antagonist, significantly (P < 0.05) increased net fluid secretion. Phenylephrine, an alpha 1-agonist, and prazosin, an alpha 1-antagonist, lacked significant effects on net fluid transport. Similarly, prenalterol, a beta 1-agonist, and metoprolol, a beta 1-antagonist, had no significant effect on the net fluid transport. The beta 2-agonist salbutamol significantly (P < 0.001) decreased net fluid secretion, while the beta-antagonist propranolol significantly (P < 0.001) decreased net fluid secretion.
Activation of alpha 2-adrenoceptors and blockade of beta 2-adrenoceptors significantly reduce net fluid secretion in small bowel obstruction. Results also demonstrate a continuous stimulatory effect on fluid secretion mediated by beta 2-receptors and a continuous inhibitory effect mediated by alpha 2-receptors.
研究肾上腺素能受体在小肠梗阻液体丢失中的重要性。
评估肾上腺素能激动剂和拮抗剂对大鼠慢性小肠梗阻体内净液体分泌的影响。
在麻醉大鼠小肠机械性梗阻18小时后，连续记录空肠段的净液体转运。对肾上腺素能受体激动剂、拮抗剂及等渗盐水对净液体转运的影响进行量化。
α2激动剂可乐定具有显著（P<0.05）的抗分泌作用，而α2拮抗剂育亨宾显著（P<0.05）增加净液体分泌。α1激动剂去氧肾上腺素和α1拮抗剂哌唑嗪对净液体转运无显著影响。同样，β1激动剂普瑞特罗和β1拮抗剂美托洛尔对净液体转运也无显著影响。β2激动剂沙丁胺醇显著（P<0.001）减少净液体分泌，而β拮抗剂普萘洛尔显著（P<0.001）减少净液体分泌。
α2肾上腺素能受体的激活和β2肾上腺素能受体的阻断可显著减少小肠梗阻时的净液体分泌。结果还表明β2受体介导对液体分泌有持续的刺激作用，α2受体介导有持续的抑制作用。
