Endomorphin-1 and endomorphin-2: pharmacology
of the selective endogenous mu-opioid receptor agonists

Horvath G.
Department of Physiology,
Faculty of Medicine and Faculty of Health Sciences,
University of Szeged, P.O. Box 427,
H-6701, Szeged, Hungary.
Pharmacol Ther 2000 Dec; 88(3):437-63


The recently discovered endogenous opioid peptides, endomorphins-1 and -2, appear to have properties consistent with neurotransmitter/neuromodulator actions in mammals. This review surveys the information gained so far from studies of different aspects of the endomorphins. Thus, the endomorphins have been found unequally in the brain; they are stored in neurons and axon terminals, with a heterogeneous distribution; they are released from synaptosomes by depolarization; they are enzymatically converted by endopeptidases; and they interact specifically and with high affinity with mu-opioid receptors. The most outstanding effect of the endomorphins is their antinociceptive action. This depends on both central and peripheral neurons. Additionally, the endomorphins cause vasodilatation by stimulating nitric oxide release from the endothelium. Their roles in different central and peripheral functions, however, have not been fully clarified yet. From a therapeutic perspective, therefore, they may be conceived at present as potent antinociceptive and vasodilator agents.
Knockout mice
Opium timeline
Opioid receptors
Endomorphins 1 and 2
The Pleasures of Opium
Endomorphins and the mouse
Endomorphins and rodent brains
Adenylyl cyclase superactivation
The degradation of endomorphins
Endomorphins and the mu-opioid receptor
Morphine: a mood-brightening smart-drug?
Opioids, depression and learned helplessness
Endomorphins to treat chronic inflammatory disease
Rewarding and psychomotor stimulant effects of endomorphin 1

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