Simonian H P, Kresge K M, Boden G H, Parkman H P
Section of Gastroenterology, Department of Medicine, Temple University School of Medicine, Philadelphia, PA 19140, USA.
Neurogastroenterol Motil. 2005 Jun;17(3):348-54. doi: 10.1111/j.1365-2982.2004.00634.x.
Ghrelin has been suggested to function as an appetite-stimulating signal from the gastrointestinal tract to the brain acting through a vagal afferent pathway. Ghrelin levels rise before meals and fall after meal ingestion. The purpose of this study was to investigate factors which regulate ghrelin release into the circulation by determining changes in systemic ghrelin concentrations after sham feeding and meal ingestion.
Fifteen normal subjects underwent sham feeding of a bacon and cheese toasted sandwich. Serial blood samples were obtained before and every 5 min for another 30 min during sham feeding and for 30 min after actual meal ingestion. Radioimmunoassay was used to measure plasma ghrelin and pancreatic polypeptide concentrations.
During sham feeding, plasma ghrelin concentration increased from 1730+/-237 to 1917+/-269 pg/mL (P<0.05) and plasma pancreatic polypeptide increased from 417+/-50 to 841+/-97 pg/mL (P<0.01). Subsequent meal ingestion was characterized by an increase in pancreatic polypeptide from 782+/-88 to 1710+/-119 pg/mL (P<0.01), but no significant change in ghrelin levels.
Plasma ghrelin and pancreatic polypeptide concentrations increase with sham feeding. This suggests a vagal efferent pathway mediating ghrelin release. In contrast to pancreatic polypeptide which rises with actual meal ingestion, ghrelin levels did not change.
胃饥饿素被认为是一种从胃肠道向大脑传递的食欲刺激信号，通过迷走神经传入途径发挥作用。胃饥饿素水平在餐前升高，餐后下降。本研究的目的是通过测定假饲和进食后全身胃饥饿素浓度的变化，探讨调节胃饥饿素释放到循环中的因素。
15名正常受试者接受了一份培根芝士烤三明治的假饲。在假饲前以及假饲期间每隔5分钟采集一次系列血样，持续30分钟，进食后再采集30分钟。采用放射免疫分析法测定血浆胃饥饿素和胰多肽浓度。
在假饲期间，血浆胃饥饿素浓度从1730±237 pg/mL增加到1917±269 pg/mL（P<0.05），血浆胰多肽从417±50 pg/mL增加到841±97 pg/mL（P<0.01）。随后的进食表现为胰多肽从782±88 pg/mL增加到1710±119 pg/mL（P<0.01），但胃饥饿素水平无显著变化。
假饲时血浆胃饥饿素和胰多肽浓度升高。这表明存在一条介导胃饥饿素释放的迷走神经传出途径。与实际进食时升高的胰多肽不同，胃饥饿素水平没有变化。
