Frolov D.S., Sibarov D.A., Vol'nova A.B.
Intranasal epitalon infusions alters spontaneous electric activity of motor neocortex in rats
Forum for European Neuroscience 2004 (10-14 July 2004, Lisbon). FENS Abstr., V.2, A025.6.

Low molecular pineal peptides are known to protect the organism against different stress factors like osmotic stress, radiation, tumor growth et al, while the mechanisms of their action remain unclear. We have performed an investigation of synthetic peptide epitalon (Ala-Glu-Asp-Gly). It has been constructed on the basis of epithalamin - pineal peptide extract - aminoacid analysis. Intranasal infusion of epitalon solution used in this study seems to be the most effective way to deliver peptide substance to CNS bypassing blood-brain barrier.
Epitalon physiological activity was evaluated according to spontaneous electric activity of rat frontal neocortex. Tiopental-anaesthetised Wistar male rats (60 mg/kg body weight, i. p. ) were fixed in stereotaxic frame in screened and grounded camera. Extracellular electric activity was recorded using glass microelectrode (1-2 MOhm). Spontaneous electric activity has been recorded for 10 minutes before and up to 30 minutes after intranasal epitalon inufusion. Epitalon caused significant (2-2, 5 times) increase in action potentials frequency on the 5-th minute after infusion. This delay between epitalon application and it’s physiological action probably reflects the time of it’s transport from nasal cavity to brain circulation. Multiple rhythmic firing of the cortical neurons was sometimes accompanied with spontaneous movements of experimental animal even under anaesthesia. It seems to be the result of epitalon physiological action. This effect disappeared in 20-30 minutes after the infusion.
This results suggest, that epitalon successfully bypasses blood-brain barrier and modulates motor cortical neuronal activity.