Article date: 1992/9/1
PubMed ID: 1359440
Journal name: Neuropharmacology (ISSN: 0028-3908)
The effects of intracerebroventricular administration of morphine, the selective mu-agonist DAMGO, the delta-agonist DPDPE, the kappa-preferring peptide dynorphin A(1-13) and the kappa-agonist U50,488H on locomotor behaviour in the guinea pig were investigated. Morphine (total dose = 0.01, 0.1, 1, 10, 200 nmol), DAMGO and DPDPE (total dose = 0.1, 1, 10, 100 nmol of each) produced piloerection and sedation, indicating that the responses of guinea pigs to mu- and delta-opioid agonists differed from those of rats and mice. In contrast, U50,488H (total dose = 10, 100 nmol) and dynorphin A(1-13) (total dose = 100 nmol) produced increased locomotor activity which was attenuated by pretreatment with naloxone and norbinaltorphimine, thus confirming the involvement of kappa-opioid receptors. Furthermore, pretreatment with spantide, baclofen, muscimol, bicuculline, MK-801, raclopride and atropine also inhibited the U50,488H-induced locomotor activity, suggesting the involvement of GABA, dopamine, excitatory amino acids, substance P and acetylcholine in this response.
Author List: Bot G, Chahl L A, Brent P J, Johnston P A
Publication Types: Journal Article
Substances mentioned in the article: Analgesics; Enkephalins; Hypnotics and Sedatives; Narcotics; Peptide Fragments; Pyrrolidines; Receptors, Opioid; Receptors, Opioid, delta; Receptors, Opioid, kappa; Receptors, Opioid, mu; Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer; dynorphin (1-13); Dynorphins; Morphine; Enkephalin, D-Penicillamine (2,5)-;
Mesh terms: 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer; Analgesics/pharmacology; Animals; Dynorphins/pharmacology; Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; Enkephalin, D-Penicillamine (2,5)-; Enkephalins/pharmacology; Female; Guinea Pigs; Hypnotics and Sedatives/pharmacology; Injections, Intraventricular; Injections, Subcutaneous; Male; Morphine/pharmacology; Motor Activity/drug effects; Narcotics/pharmacology; Peptide Fragments/pharmacology; Piloerection/drug effects; Pyrrolidines/pharmacology; Receptors, Opioid/drug effects; Receptors, Opioid, delta/drug effects; Receptors, Opioid, kappa/drug effects; Receptors, Opioid, mu/drug effects;