Falkmer S, Fahrenkrug J, Alumets J, Håkanson R, Sundler F
Endocrinol Jpn. 1980 Dec;27 Suppl 1:31-5. doi: 10.1507/endocrj1954.27.supplement_31.
As part of study of the phylogeny of VIP, it was observed that the colonic mucosa of the cartilaginous fish, Raja radiata and Raja clavata, contained numerous epithelial cells, obviously of closed type, displaying intense VIP immunoreactivity. Accordingly, high concentrations of VIP were found by radioimmunoassay. At the ultrastructural level, the VIP cells were characterized by the presence of highly electron dense secretory granules. The colonic mucosa of the ray may be a good source for the isolation of an early VIP.
作为对血管活性肠肽（VIP）系统发育研究的一部分，研究人员观察到，软骨鱼类辐射鳐和欧洲鳐的结肠黏膜含有大量明显为封闭型的上皮细胞，这些细胞呈现出强烈的VIP免疫反应性。因此，通过放射免疫测定法发现了高浓度的VIP。在超微结构水平上，VIP细胞的特征是存在高度电子致密的分泌颗粒。鳐鱼的结肠黏膜可能是分离早期VIP的良好来源。
