Simmaco M, Severini C, De Biase D, Barra D, Bossa F, Roberts J D, Melchiorri P, Erspamer V
Dipartimento di Scienze Biochimiche, Università di Roma La Sapienza, Italy.
Peptides. 1990 Mar-Apr;11(2):299-304. doi: 10.1016/0196-9781(90)90086-k.
Six novel peptides belonging to the tachykinin and bombesin families were isolated and sequenced from extracts of the skin of the Australian myobatrachid frog Pseudophryne güntheri. One of these peptides (PG-L) was of the bombesin family and may be considered an N-elongation of the litorin/ranatensin molecule, with which it shares an identical spectrum of activity on isolated smooth muscle preparations. The other five peptides were of the tachykinin family with two of these peptides (PG-SPI and PG-SPII) related to substance P and three (PG-KI, PG-KII and PG-KIII) to kassinin. In contrast to the basic nature of substance P, the PG-SP peptides showed a clear acidic character and displayed a more potent and sustained action on isolated smooth muscle preparations and rat blood pressure than did substance P. Two of the three PG-K peptides were more potent than kassinin; PG-KIII was considerably less potent. PG-KI and PG-KII were also present in a deamidated, poorly active, form.
从澳大利亚肌蛙科蛙类冈氏伪蛙（Pseudophryne güntheri）皮肤提取物中分离并测序出六种属于速激肽和铃蟾肽家族的新型肽。其中一种肽（PG-L）属于铃蟾肽家族，可被视为利托林/蛙皮降压肽分子的N端延伸，它在离体平滑肌制剂上具有与利托林/蛙皮降压肽相同的活性谱。另外五种肽属于速激肽家族，其中两种肽（PG-SPI和PG-SPII）与P物质相关，三种（PG-KI、PG-KII和PG-KIII）与肛褶蛙素相关。与P物质的碱性性质不同，PG-SP肽具有明显的酸性特征，并且在离体平滑肌制剂和大鼠血压上比P物质表现出更强且更持久的作用。三种PG-K肽中的两种比肛褶蛙素更有效；PG-KIII的效力则明显较低。PG-KI和PG-KII也以脱酰胺的、活性较差的形式存在。
