Wøjdemann M, Wettergren A, Hartmann B, Holst J J
Dept. of Surgical Gastroenterology, Rigshospitalet, The National University Hospital, Copenhagen, Denmark.
Scand J Gastroenterol. 1998 Aug;33(8):828-32. doi: 10.1080/00365529850171486.
Glucagon-like peptide-2 is formed from proglucagon in the intestinal L-cells and is secreted postprandially in parallel with the insulinotropic hormone GLP-1 (glucagon-like peptide-1), which in addition acts to inhibit gastric motility (enterogastrone effect) by inhibiting central parasympathetic outflow. GLP-2 has no effect on the endocrine pancreas. We here tested the hypothesis that GLP-2 acts as an enterogastrone.
Fourteen anesthetized pigs with their splanchnic nerves cut were subjected to insulin hypoglycemia, and force transducers were sutured to the antrum to record motility. GLP-2 was infused intravenously in doses from 1 to 6 pmol/kg/min after the onset of antral motility in response to hypoglycemia.
Insulin hypoglycemia invariably and greatly increased the frequency and amplitude of antral phasic contractions. Infusions of GLP-2 dose dependently (1-6 pmol/kg/min) inhibited antral motility. At 2 pmol/kg/min, resulting in plasma GLP-2 concentrations of 102.5+/-19 pmol/l (normal postprandial range, 30-82 pmol/l), the motility index was inhibited by 91%+/-14%.
Both of the intestinal glucagon-like peptides may operate as hormonal transmitters of the ileal brake effect.
胰高血糖素样肽-2由肠道L细胞中的胰高血糖素原生成,在餐后与促胰岛素激素胰高血糖素样肽-1(GLP-1)同时分泌,后者还通过抑制中枢副交感神经传出而发挥抑制胃动力的作用(肠抑胃素效应)。GLP-2对内分泌胰腺无作用。我们在此检验了GLP-2作为肠抑胃素发挥作用的假说。
对14只切断内脏神经的麻醉猪进行胰岛素低血糖处理,将力传感器缝合于胃窦以记录动力。在胃窦出现对低血糖的动力反应后,以1至6 pmol/kg/分钟的剂量静脉输注GLP-2。
胰岛素低血糖总是会极大地增加胃窦相性收缩的频率和幅度。GLP-2输注呈剂量依赖性(1 - 6 pmol/kg/分钟)抑制胃窦动力。在2 pmol/kg/分钟时,血浆GLP-2浓度达到102.5±19 pmol/l(正常餐后范围为30 - 82 pmol/l),动力指数被抑制91%±14%。
两种肠道胰高血糖素样肽都可能作为回肠制动效应的激素传递介质发挥作用。