在五指细趾蟾和非洲爪蟾的皮肤提取物中存在蛙皮素。

Presence of caerulein in extracts of the skin of Leptodactylus pentadactylus labyrinthicus and of Xenopus laevis.

Anastasi A, Bertaccini G, Cei J M, De Caro G, Erspamer V, Impicciatore M, Roseghini M

Br J Pharmacol. 1970 Jan;38(1):221-8. doi: 10.1111/j.1476-5381.1970.tb10351.x.

The South American amphibian Leptodactylus pentadactylus labyrinthicus and the South African amphibian Xenopus laevis contain in their skin a polypeptide indistinguishable from caerulein prepared from the Australian amphibian Hyla caerulea.2. The caerulein content of different batches of Leptodactylus pentadactylus labyrinthicus skins varies from 10 to 500-600 mug/g tissue. Drying of the skin causes either a moderate decrease or a slight increase in the caerulein content. Methanol extraction gives considerably higher yields of caerulein than acetone extraction.3. Caerulein or caerulein-like polypeptides also occur in the skin of several other species of Leptodactylus together with 5-hydroxyindole alkylamines and imidazole alkylamines. Yet other species of Leptodactylus lack caerulein-like polypeptides and 5-hydroxyindole alkylamines.4. It is suggested that caerulein and caerulein-like polypeptides may have some function either in the regulation of secretory processes of the skin or in the exchange of water and electrolytes through the skin, or in both.

南美两栖动物五指细趾蟾和南非两栖动物非洲爪蟾的皮肤中含有一种多肽，该多肽与从澳大利亚两栖动物蓝树蛙制备的雨蛙素无法区分。
不同批次的五指细趾蟾皮肤中雨蛙素的含量在10至500 - 600微克/克组织之间变化。皮肤干燥会导致雨蛙素含量适度降低或略有增加。甲醇提取得到的雨蛙素产量比丙酮提取高得多。
雨蛙素或雨蛙素样多肽也存在于其他几种细趾蟾属物种的皮肤中，同时还存在5 - 羟色胺烷基胺和咪唑烷基胺。然而，其他细趾蟾属物种缺乏雨蛙素样多肽和5 - 羟色胺烷基胺。
有人提出，雨蛙素和雨蛙素样多肽可能在调节皮肤分泌过程或通过皮肤进行水和电解质交换方面具有某种功能，或者在这两方面都有功能。

Presence of caerulein in extracts of the skin of Leptodactylus pentadactylus labyrinthicus and of Xenopus laevis.