Dimaline R
Peptides. 1983 Jul-Aug;4(4):457-62. doi: 10.1016/0196-9781(83)90049-9.
The amphibian skin decapeptide caerulein is structurally related to the mammalian peptides gastrin and CCK, suggesting that the peptides might share a common evolutionary history. It has been suggested that caerulein is the amphibian counterpart of gastrin and CCK, and that the Amphibia do not possess authentic gastric and CCK. High Performance Liquid Chromatography (HPLC) in conjunction with radioimmunoassay using a caerulein-specific antiserum and C-terminal CCK antisera, was used to characterize CCK-and caerulein-like peptides in amphibian brain and gut. In the brain of Xenopus laevis, two CCK-like peptides were present, one of which was indistinguishable by HPLC from mammalian CCK8. No decapeptide caerulein was detected in the brain of Xenopus laevis or Rana temporaria. In the stomach of Xenopus and in the intestine of both species studied, CCK-like and caerulein-like peptides were present. The results indicate therefore that the Amphibia possess CCK8-like rather than caerulein-like peptides in brain. In contrast, stomach and intestine contain both CCK-like and caerulein-like peptides, but the latter are however distinguishable from the decapeptide found in skin.
两栖动物皮肤十肽蛙皮素在结构上与哺乳动物肽胃泌素和胆囊收缩素相关，这表明这些肽可能有着共同的进化史。有人提出蛙皮素是胃泌素和胆囊收缩素在两栖动物中的对应物，并且两栖动物没有真正的胃泌素和胆囊收缩素。利用高效液相色谱（HPLC）结合使用蛙皮素特异性抗血清和C末端胆囊收缩素抗血清的放射免疫分析法，对两栖动物脑和肠道中的胆囊收缩素样肽和蛙皮素样肽进行了表征。在非洲爪蟾的脑中，存在两种胆囊收缩素样肽，其中一种通过HPLC分析与哺乳动物的胆囊收缩素-8无法区分。在非洲爪蟾或欧洲林蛙的脑中未检测到十肽蛙皮素。在非洲爪蟾的胃以及所研究的两种动物的肠道中，均存在胆囊收缩素样肽和蛙皮素样肽。因此，结果表明两栖动物脑中存在的是胆囊收缩素-8样肽而非蛙皮素样肽。相比之下，胃和肠道中同时含有胆囊收缩素样肽和蛙皮素样肽，但后者与在皮肤中发现的十肽有所不同。
