» Articles » PMID: 3801765

The Contribution of Intrinsic Activity to the Action of Opioids in Vitro

Overview
Journal Br J Pharmacol
Publisher Wiley
Specialty Pharmacology
Date 1986 Mar 1
PMID 3801765
Citations 24
Authors
Affiliations
Soon will be listed here.
Abstract

The effects of opioids were compared in five field-stimulated isolated tissue models, the guinea-pig ileum and vasa deferentia from rat, rabbit and mice of the Alderley Park and C57BL/6 strains. Although the mu-receptor agonist [D-Ala2, MePhe4, Gly-ol5] enkephalin appeared to act at similar receptors in the guinea-pig ileum, rat vas deferens, mouse vas deferens and C57BL/6 mouse vas deferens preparations, its potency varied considerably between these preparations. Similar potency differences were also observed with the kappa-agonist, ethylketocyclazocine. It is proposed that these variations in potency reflect differences in the number of spare receptors present in each model. The finding that some drugs which have agonist activity in the more sensitive preparations behave as antagonists in the less sensitive tissues supports this proposal and highlights the importance of intrinsic activity in determining the action of opioids. Many of the prototypic opioid agonists were found to be either partial agonists (eg. morphine and bremazocine) or to possess affinity for more than one receptor type (eg. ethylketocyclazocine, Mr 2034).

Citing Articles

Physiologically based pharmacokinetic/pharmacodynamic model for the prediction of morphine brain disposition and analgesia in adults and children.

Verscheijden L, Litjens C, Koenderink J, Mathijssen R, Verbeek M, de Wildt S PLoS Comput Biol. 2021; 17(3):e1008786.

PMID: 33661919 PMC: 7963108. DOI: 10.1371/journal.pcbi.1008786.


Concurrent Assessment of the Antinociceptive and Behaviorally Disruptive Effects of Opioids in Squirrel Monkeys.

Withey S, Paronis C, Bergman J J Pain. 2018; 19(7):728-740.

PMID: 29477761 PMC: 6026058. DOI: 10.1016/j.jpain.2018.02.003.


Impact of efficacy at the μ-opioid receptor on antinociceptive effects of combinations of μ-opioid receptor agonists and cannabinoid receptor agonists.

Maguire D, France C J Pharmacol Exp Ther. 2014; 351(2):383-9.

PMID: 25194020 PMC: 4201274. DOI: 10.1124/jpet.114.216648.


Pharmacological examination of contractile responses of the guinea-pig isolated ileum produced by mu-opioid receptor antagonists in the presence of, and following exposure to, morphine.

Mundey M, Ali A, Mason R, Wilson V Br J Pharmacol. 2000; 131(5):893-902.

PMID: 11053208 PMC: 1572416. DOI: 10.1038/sj.bjp.0703659.


Pharmacological comparison of the effect of ibogaine and 18-methoxycoronaridine on isolated smooth muscle from the rat and guinea-pig.

Mundey M, Blaylock N, Mason R, Glick S, Maisonneuve I, Wilson V Br J Pharmacol. 2000; 129(8):1561-8.

PMID: 10780959 PMC: 1571996. DOI: 10.1038/sj.bjp.0703227.


References
1.
Paton W, Zar M . The origin of acetylcholine released from guinea-pig intestine and longitudinal muscle strips. J Physiol. 1968; 194(1):13-33. PMC: 1365672. DOI: 10.1113/jphysiol.1968.sp008392. View

2.
McKnight A, Corbett A, Marcoli M, KOSTERLITZ H . Hamster vas deferens contains delta-opioid receptors. Neuropeptides. 1984; 5(1-3):97-100. DOI: 10.1016/0143-4179(84)90036-2. View

3.
LORD J, Waterfield A, Hughes J, KOSTERLITZ H . Endogenous opioid peptides: multiple agonists and receptors. Nature. 1977; 267(5611):495-9. DOI: 10.1038/267495a0. View

4.
Waterfield A, LORD J, Hughes J, KOSTERLITZ H . Differences in the inhibitory effects of normorphine and opioid peptides on the responses of the vasa deferentia of two strains of mice. Eur J Pharmacol. 1978; 47(2):249-50. DOI: 10.1016/0014-2999(78)90399-0. View

5.
Schulz R, Faase E, Wuster M, Herz A . Selective receptors for beta-endorphin on the rat vas deferens. Life Sci. 1979; 24(9):843-9. DOI: 10.1016/0024-3205(79)90368-0. View