Peptide ACTH-PGP: Effects on Various Types of Pain and Pain-Induced Behavior in Rats after Systemic and Central Administration.

Bulletin of experimental biology and medicine2020PMID: 33263853

View on PubMed DOI: 10.1007/s10517-020-05029-8

Animal StudySemax

Plain Language Summary

Semax produced different effects on pain depending on the type of stimulus: it increased sensitivity to heat pain but had an analgesic effect — and reduced emotional distress — when pain was caused by electrical stimulation. The effect was more pronounced when Semax was delivered directly into the brain, pointing to brain-level (rather than spinal) mechanisms as primary drivers of how the peptide modulates pain responses and associated behavior.

Abstract

The effects of peptide ACTH4-7-PGP (Semax) were studied in 12 min after its intraperitoneal (in doses of 5, 15, 50, 150, and 450 μg/kg) or intracerebroventricular (in doses of 16, 40, and 400 pg) administration to rats with different types of pain and pain-induced behavior. It was found that the peptide increased pain sensitivity and induced avoidance behavior during thermal stimulation ("hot plate" test), but had an analgesic effect (more pronounced after central administration) and weakened emotional-affective behavior in electrocutaneous stimulation of the paws (foot-shock model) and tail in rats. It was shown that changes in activity of supraspinal brain structures were of primary importance in the mechanism of action on the nociceptive process and the formation of behavior.

Authors

Severyanova, L A; Kryukov, A A; Plotnikov, D V; Dolgintsev, M E

Keywords

aggressionpainpain-induced behaviorregulatory peptides