Eledoisin is a peptide extracted from the posterior salivary glands of certain small octopi (Eledone spp., Mollusca), or obtained by synthesis. Its actions resemble those of substance p; it is a potent vasodilator and increases capillary permeability.
At the end of therapy it was possible to match the beneficial effects of eye drops with carnitin, taurine, sodium hyaluronate and eledoisin. In fact, after 15days of treatment, patients of group 1 showed a decrease of approximately 50% concerning the severity of symptoms and a significant improvement of the tests valued.
Nebbioso, M., Evangelista, M., Librando, A., Plateroti, A. M., & Pescosolido, N. (2013). Iatrogenic dry eye disease: an eledoisin/carnitine and osmolyte drops study. Biomedicine & Pharmacotherapy, 67(7), 659-663.
Both the aqueous and the lipid-induced structure of eledoisin, an undecapeptide of mollusk origin, have been studied by two-dimensional proton nuclear magnetic resonance spectroscopy and distance geometry calculations. Unambiguous nuclear magnetic resonance assignments of protons have been made with the aid of correlation spectroscopy experiments and nuclear Overhauser effect spectroscopy experiments. The distance constraints obtained from the nuclear magnetic resonance data have been utilized in a distance geometry algorithm to generate a family of structures, which have been refined using restrained energy minimization and dynamics.
Grace, R. C. R., Chandrashekar, I. R., & Cowsik, S. M. (2003). Solution structure of the tachykinin peptide eledoisin. Biophysical journal, 84(1), 655-664.
The tachykinin peptide family certainly represents one of the largest peptide families described in the animal organism. So far, more than 40 tachykinins have been isolated from invertebrate (insects, worms, and molluscs), protochordate, and vertebrate (skin, gastrointestinal tract, peripheral and central nervous system) tissues. Substance P (SP), first identified by bioassay as early as 1931 but sequenced only in 1971, several years after the elucidation of the structure of eledoisin from molluscan tissues and of physalaemin from amphibian skin, may be considered as a prototype of the tachykinins.
Severini, C., Improta, G., Falconieri-Erspamer, G., Salvadori, S., & Erspamer, V. (2002). The tachykinin peptide family. Pharmacological reviews, 54(2), 285-322.