Biomaterial Database

The dopamine D4 receptor antagonist L-745,870: effects in rats discriminating cocaine from saline. 1998

R M Costanza, and P Terry

School of Psychology, University of Birmingham, Edgbaston, UK.

The contribution of dopamine D4 receptors to the discriminative stimulus effects of cocaine was evaluated by testing the selective dopamine D4 receptor antagonist, L-745,870 (3-([4-(4-chlororphenyl) piperazin-1-yl] methyl)-1 H-pyrrolo[2,3-b] pyridine), alone and in combination with cocaine, in rats trained to discriminate cocaine (10 mg/kg) from saline. The antagonist (1-10 mg/kg) failed to engender cocaine-appropriate responding when injected alone, and failed to modify the cocaine dose-response curve when injected as a pre-treatment; however, it reduced response rates dose-dependently. Conversely, the dopamine 'D1-like' receptor antagonist, SCH 39166 ((-)-trans-6,7,7a,8,9, 13b-hexahydro-3-chloro-2hydroxy-N-methyl-5H-benzo[d]napth o-¿2,1-b¿azepine, produced surmountable antagonism. Results suggest that dopamine D4 receptors play a negligible role in cocaine's discriminative stimulus effects, and further support a critical involvement of dopamine D1-like receptors.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D011725	Pyridines	Compounds with a six membered aromatic ring containing NITROGEN. The saturated version is PIPERIDINES.
D011758	Pyrroles	Azoles of one NITROGEN and two double bonds that have aromatic chemical properties.	Pyrrole
D003042	Cocaine	An alkaloid ester extracted from the leaves of plants including coca. It is a local anesthetic and vasoconstrictor and is clinically used for that purpose, particularly in the eye, ear, nose, and throat. It also has powerful central nervous system effects similar to the amphetamines and is a drug of abuse. Cocaine, like amphetamines, acts by multiple mechanisms on brain catecholaminergic neurons; the mechanism of its reinforcing effects is thought to involve inhibition of dopamine uptake.	Cocaine HCl,Cocaine Hydrochloride,HCl, Cocaine,Hydrochloride, Cocaine
D003216	Conditioning, Operant	Learning situations in which the sequence responses of the subject are instrumental in producing reinforcement. When the correct response occurs, which involves the selection from among a repertoire of responses, the subject is immediately reinforced.	Instrumental Learning,Learning, Instrumental,Operant Conditioning,Conditionings, Operant,Instrumental Learnings,Learnings, Instrumental,Operant Conditionings
D004192	Discrimination, Psychological	Differential response to different stimuli.	Discrimination, Psychology,Psychological Discrimination
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D017207	Rats, Sprague-Dawley	A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.	Holtzman Rat,Rats, Holtzman,Sprague-Dawley Rat,Rats, Sprague Dawley,Holtzman Rats,Rat, Holtzman,Rat, Sprague-Dawley,Sprague Dawley Rat,Sprague Dawley Rats,Sprague-Dawley Rats
D017448	Receptors, Dopamine D2	A subfamily of G-PROTEIN-COUPLED RECEPTORS that bind the neurotransmitter DOPAMINE and modulate its effects. D2-class receptor genes contain INTRONS, and the receptors inhibit ADENYLYL CYCLASES.	Dopamine D2 Receptors,Dopamine-D2 Receptor,D2 Receptors, Dopamine,Dopamine D2 Receptor,Receptor, Dopamine-D2
D050638	Receptors, Dopamine D4	A subtype of dopamine D2 receptors that has high affinity for the antipsychotic CLOZAPINE.	Dopamine D4 Receptors,Dopamine D4 Receptor,Receptor, Dopamine D4,D4 Receptor, Dopamine,D4 Receptors, Dopamine