Changes in brain, plasma and cerebrospinal fluid contents of beta-endorphin in dogs at the moment of death.

Abstract

To investigate the possible participation of endogenous opioids in the cerebral events that take place at the moment of death we studied brain, cerebrospinal fluid and serum contents of beta-endorphin in dogs that were either conscious or unconscious at the moment of sudden death induced by cardiac arrest. Although with great interindividual variations, the animals that were conscious at the moment of cardiac arrest, presented a significant increase in beta-endorphin when compared with their own previous values (p < 0.05) or with the values found in animals that were deeply anaesthetized at the time of cardiac arrest. There seems to be a sudden increment of beta-endorphin in brain tissue and body fluids of dogs who are conscious at the moment of sudden death, this change was not observed in dogs that were anaesthetized prior to death. Brain opioids could participate in the sensations narrated by subjects in the so called near-death experience.