TY - JOUR

T1 - Effects of intranasal administration of epitalon on neuron activity in the rat neocortex

AU - Sibarov, D. A.

AU - Vol'nova, A. B.

AU - Frolov, D. S.

AU - Nozdrachev, A. D.

PY - 2007/11/1

Y1 - 2007/11/1

N2 - This report discusses the properties of the synthetic tetrapeptide epitalon (Ala-Glu-Asp-Gly), synthesized on the basis of an epiphyseal peptide extract. Intranasal administration of epitalon was selected as a noninvasive means of applying the agent to the CNS by bypassing the blood-brain barrier. The aim of the present work was to assess the characteristics of the action of epitalon on the frequency of spontaneous neuron activity in the cerebral cortex of white rats. Studies were performed using male Wistar rats anesthetized with urethane (1 g/kg). Extracellular activity of cortical neurons was recorded with a glass microelectrode of resistance 1-2 MΩ. Recording of spontaneous neuron discharges for 10-15 min was followed by intranasal administration of epitalon solution and recording of neuron activity to 30 min after doses of 30 ng per animal. Significant activation of neuron activity was seen several minutes after dosage, with an increase (by factors of 2-2.5) in discharge frequency. In some experiments, the effect of epitalon was multiphasic. The first peak of increased neuron discharge frequency at 5-7 min was followed by peaks at 11-12 and 17-18 min. The increase in discharge frequency occurred because of an increase in the discharge frequency of neurons which were already active and the recruitment of previously silent neurons. At least the first peak of increased neuron activity following exposure to epitalon was found to be associated with the direct action of the peptide on cortical cells.

AB - This report discusses the properties of the synthetic tetrapeptide epitalon (Ala-Glu-Asp-Gly), synthesized on the basis of an epiphyseal peptide extract. Intranasal administration of epitalon was selected as a noninvasive means of applying the agent to the CNS by bypassing the blood-brain barrier. The aim of the present work was to assess the characteristics of the action of epitalon on the frequency of spontaneous neuron activity in the cerebral cortex of white rats. Studies were performed using male Wistar rats anesthetized with urethane (1 g/kg). Extracellular activity of cortical neurons was recorded with a glass microelectrode of resistance 1-2 MΩ. Recording of spontaneous neuron discharges for 10-15 min was followed by intranasal administration of epitalon solution and recording of neuron activity to 30 min after doses of 30 ng per animal. Significant activation of neuron activity was seen several minutes after dosage, with an increase (by factors of 2-2.5) in discharge frequency. In some experiments, the effect of epitalon was multiphasic. The first peak of increased neuron discharge frequency at 5-7 min was followed by peaks at 11-12 and 17-18 min. The increase in discharge frequency occurred because of an increase in the discharge frequency of neurons which were already active and the recruitment of previously silent neurons. At least the first peak of increased neuron activity following exposure to epitalon was found to be associated with the direct action of the peptide on cortical cells.

KW - Epitalon

KW - Intranasal administration

KW - Microelectrodes

KW - Neocortex

KW - Peptide

UR - http://www.scopus.com/inward/record.url?scp=38449095957&partnerID=8YFLogxK

U2 - 10.1007/s11055-007-0095-3

DO - 10.1007/s11055-007-0095-3

M3 - Article

C2 - 17955380

AN - SCOPUS:38449095957

VL - 37

SP - 889

EP - 893

JO - Neuroscience and Behavioral Physiology

JF - Neuroscience and Behavioral Physiology

SN - 0097-0549

IS - 9

ER -