Endorphins: Profound Behavioral Effects in Rats Suggest New Etiological Factors in Mental Illness
SciencePublished 5 November 1976
Floyd E. Bloom, David J. Segal, Nicholas Ling, Roger Guillemin
Citations812
SJR quartileQ1
SJR score10.42
SNIP6.62
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TL;DR
The endogenous morphinomimetic brain peptides Met5-enkephalin and alpha-, beta-, and gamma-endorphins have been evaluated in rats after intracerebrospinal fluid injection and their potent and divergent responses to naturally occurring subtances suggest that alterations in their homeostatic regulation could have etiological significance in mental illness.
Abstract
The endogenous morphinomimetic brain peptides Met5-enkephalin and alpha-, beta-, and gamma-endorphins have been evaluated in rats after intracerebrospinal fluid injection. beta-Endorphin produces marked, prolonged muscular rigidity and immobility similar to a catatonic state, counteracted by the opiate antagonist naloxone; this effect occurs at molar doses 1/100 to 1/400 that at which the other peptides or morphine block the response to painful stimuli. All peptides evoked dose-related, naloxone-reversible, wet-dog shakes in rats that had not been exposed to drugs. beta-Endorphin produced hypothermia, whereas gamma-endorphin produced hyperthermia. Such potent and divergent responses to naturally occurring subtances suggest that alterations in their homeostatic regulation could have etiological significance in mental illness.
Keywords
PsychologyNeuroscienceBiochemistry, Genetics and Molecular Biology
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