Frandsen E K, Thim L, Moody A J, Markussen J
J Biol Chem. 1985 Jun 25;260(12):7581-4.
Glucagon-(1-21) was prepared fully synthetically as well as by carboxypeptidase A digestion of natural porcine glucagon. Neither of the two preparations had glucagon agonistic effects with regard to receptor binding or adenylate cyclase activation in purified rat liver plasma membranes. Nor did these preparations contain lipolytic activity in isolated free fat cells. A preliminary batch of glucagon-(1-21) prepared by carboxypeptidase A digestion did, however, contain 1-2% glucagon bioactivity. This activity was separated from glucagon-(1-21) by high-performance liquid chromatography and quantitatively recovered in four minor hind peaks which eluted close to but not in a position identical to the elution position of native glucagon.
胰高血糖素-(1-21)通过全合成以及用羧肽酶A消化天然猪胰高血糖素来制备。这两种制剂在纯化的大鼠肝质膜中,就受体结合或腺苷酸环化酶激活而言,均无胰高血糖素激动作用。这些制剂在分离的游离脂肪细胞中也不具有脂解活性。然而,通过羧肽酶A消化制备的一批初步的胰高血糖素-(1-21)确实含有1%-2%的胰高血糖素生物活性。这种活性通过高效液相色谱与胰高血糖素-(1-21)分离,并在四个较小的后峰中定量回收,这些峰的洗脱位置接近但与天然胰高血糖素的洗脱位置不完全相同。