Opiate activity and receptor selectivity of dynorphin1-13 and related peptides.
Experiments on the mouse vas deferens preparation obtained from animals chronically pretreated with selective opioid agonists have revealed the existence of opiate receptors with a high degree of preference for dynorphin1-13, alpha-neoendorphin1-8 and the eta-agonist MR 2034. Modification of the dynorphin sequence, by introduction of D-alanine into position 2, resulted in a complete loss of dynorphin-like agonistic activity on the tolerant mouse vas deferens. None of the dynorphin-related peptides tested displayed a pronounced opiate-like antinociception when administered intracerebroventricularly into rats.
D000818:Animals; D001667:Binding, Competitive; D004399:Dynorphins; D004723:Endorphins / Q000378:metabolism*; D009119:Muscle Contraction / Q000187:drug effects; D009294:Narcotics / Q000494:pharmacology*; D009619:Nociceptors / Q000187:drug effects; D010446:Peptide Fragments / Q000378:metabolism*; D051381:Rats; D011957:Receptors, Opioid / Q000378:metabolism*
D004723:Endorphins; D009294:Narcotics; D010446:Peptide Fragments; D011957:Receptors, Opioid; C026843:dynorphin (1-13); D004399:Dynorphins