Antihypoxic properties of opiates and substance P
Vlasova, I.G.; Torshin, V.I.
Patologicheskaia Fiziologiia i Eksperimental'naia Terapiia 2: 13-15
2001
ISSN/ISBN: 0031-2991 PMID: 11550360 Document Number: 536335
Using survival slices of the rat cerebellum, we studied the influence of opiates (alpha- and beta-endorphines, met-enkephalines) as well as substance P (SP) on the impulse activity (IA) of neurons. Low doses of the studied substances (10(-8)-10(-10) M) for the most part increased the IA of the neurons, while high doses (10(6)-10(-5) M) produced biphasic reaction (inhibition-excitation). It is supposed that opiates and SP act as transmitters in the cerebellum. Under increasing hypoxia, opiates and SP manifested antixypoxic properties both in low O22 concentration and under reoxygenation. Opiates and SP proved to be natural antihypoxants involved not only in nociception mechanisms but also in brain adaptation to oxygen deficiency.