胰多肽。犬体内的代谢及其对胰腺分泌的影响。

Pancreatic polypeptide. Metabolism and effect on pancreatic secretion in dogs.

作者信息

Taylor I L, Solomon T E, Walsh J H, Grossman M I

出版信息

Gastroenterology. 1979 Mar;76(3):524-8.

Abstract

In dogs with gastric and pancreatic fistulas, porcine pancreatic polypeptide (PP) was infused intravenously in doses of 50, 100, 200, 400, and 800 pmol kg-1 hr-1 in the basal state and in doses of 100, 200, and 400 pmol kg-1 hr-1 during stimulation with submaximal doses of secretin (125 ng kg-1 hr-1) plus caerulein (50 ng kg-1 hr-1). Plasma concentrations of PP were measured by radioimmunoassay, and pancreatic bicarbonate and protein outputs were monitored. The half-time for disappearance of PP was 5.5 +/- 1.0 min, the metabolic clearance rate was 25.6 +/- 1.0 ml kg-1, and the volume of distribution was 209 +/- 42 ml kg-1. Basal pancreatic flow and protein output were significantly inhibited by the lowest dose of PP tested, 50 pmol kg-1 hr-1. The lowest dose of PP significantly inhibiting stimulated pancreatic secretion was 100 pmol kg-1 hr-1 for bicarbonate output and 200 pmol kg-1 hr-1 for protein output. The mean +/- SE peak increment in PP concentration in response to a meal of meat, 210 +/- 39 pM, was greater than the mean peak increment with the 400 pmol kg-1 hr-1 dose of exogenous PP, 175 +/- 19 PM. We conclude that exogenous doses of PP that produce smaller increments in PP concentration than those seen after feeding inhibit pancreatic bicarbonate and protein secretion stimulated by secretin and caerulein. This suggests that the amount of PP released by a meal is sufficient to inhibit pancreatic secretion.

摘要

在患有胃瘘和胰瘘的犬中，在基础状态下以50、100、200、400和800 pmol kg⁻¹ hr⁻¹的剂量静脉输注猪胰多肽（PP），并在以次最大剂量的促胰液素（125 ng kg⁻¹ hr⁻¹）加蛙皮素（50 ng kg⁻¹ hr⁻¹）刺激期间以100、200和400 pmol kg⁻¹ hr⁻¹的剂量静脉输注。通过放射免疫测定法测量PP的血浆浓度，并监测胰腺碳酸氢盐和蛋白质的分泌量。PP消失的半衰期为5.5±1.0分钟，代谢清除率为25.6±1.0 ml kg⁻¹，分布容积为209±42 ml kg⁻¹。所测试的最低剂量的PP，即50 pmol kg⁻¹ hr⁻¹，可显著抑制基础胰腺分泌量和蛋白质分泌量。抑制刺激后胰腺分泌的PP最低剂量，对于碳酸氢盐分泌量为100 pmol kg⁻¹ hr⁻¹，对于蛋白质分泌量为200 pmol kg⁻¹ hr⁻¹。进食一顿肉后PP浓度的平均±标准误峰值增量为210±39 pM，大于外源性PP剂量为400 pmol kg⁻¹ hr⁻¹时的平均峰值增量，即175±19 pM。我们得出结论，外源性PP剂量导致的PP浓度增量小于进食后所见增量时，可抑制促胰液素和蛙皮素刺激的胰腺碳酸氢盐和蛋白质分泌。这表明一顿饭释放的PP量足以抑制胰腺分泌。