Sallam H S, Oliveira H M, Gan H T, Herndon D N, Chen J D Z
Division of Gastroenterology, Department of Internal Medicine and Surgery, University of Texas Medical Branch, Galveston, TX 77555, USA.
Am J Physiol Regul Integr Comp Physiol. 2007 Jan;292(1):R253-7. doi: 10.1152/ajpregu.00100.2006. Epub 2006 Sep 7.
Delayed gastrointestinal transit is common in patients with severe burn. Ghrelin is a potent prokinetic peptide. We aimed at testing the effect of ghrelin on burn-induced delayed gastrointestinal transit in rats. Gastric emptying (GE), intestinal transit (IT), and colonic transit (CT) studies were performed in male Sprague-Dawley rats. Rats were randomized into two main groups as follows: sham injury and ghrelin-treated burn injury with doses of 0, 2, 5, and 10 nmol/rat ip 6 h after burn. Sham/burn injury was induced under anesthesia. Rats received a phenol red meal 20 min following ghrelin injection. Based on the most effective ghrelin dose, 1 mg/kg sc atropine was given 30 min before the ghrelin in one group of rats for each study. The rats in each group were killed 30-90 min later; their stomachs, intestines, and colons were harvested immediately, and the amount of phenol red recovered was measured. Percentage of gastric emptying (GE%) and geometric center for IT and CT were calculated. We found 1) severe cutaneous burn injury significantly delayed GE, IT, and CT compared with sham injury (P < 0.05); 2) ghrelin normalized both GE and IT, but not the CT; 3) the most effective dose of ghrelin was 2 nmol/rat; and 4) atropine blocked the prokinetic effects of ghrelin on GE% and IT. In conclusion, ghrelin normalizes burn-induced delayed GE and IT but has no effect on CT in rats. The prokinetic effects of ghrelin are exerted via the cholinergic pathway. Ghrelin may have a therapeutic potential for burn patients with delayed upper gastrointestinal transit.
严重烧伤患者常出现胃肠传输延迟。胃饥饿素是一种有效的促动力肽。我们旨在测试胃饥饿素对大鼠烧伤诱导的胃肠传输延迟的影响。对雄性Sprague-Dawley大鼠进行胃排空（GE）、肠道传输（IT）和结肠传输（CT）研究。大鼠被随机分为两个主要组：假损伤组和胃饥饿素治疗的烧伤损伤组，烧伤后6小时腹腔注射剂量为0、2、5和10 nmol/只大鼠。在麻醉下诱导假/烧伤损伤。胃饥饿素注射后20分钟，大鼠接受酚红餐。根据最有效的胃饥饿素剂量，在每组大鼠进行每项研究时，在胃饥饿素注射前30分钟皮下注射1 mg/kg阿托品。30 - 90分钟后处死每组大鼠；立即取出它们的胃、肠和结肠，并测量回收的酚红量。计算胃排空百分比（GE%）以及IT和CT的几何中心。我们发现：1）与假损伤相比，严重皮肤烧伤损伤显著延迟了GE、IT和CT（P < 0.05）；2）胃饥饿素使GE和IT恢复正常，但对CT无作用；3）胃饥饿素的最有效剂量为2 nmol/只大鼠；4）阿托品阻断了胃饥饿素对GE%和IT的促动力作用。总之，胃饥饿素使大鼠烧伤诱导的延迟GE和IT恢复正常，但对CT无作用。胃饥饿素的促动力作用是通过胆碱能途径发挥的。胃饥饿素可能对伴有上消化道传输延迟的烧伤患者具有治疗潜力。
