Biomaterial Database

Morphine dependence and dopaminergic activity: tests of circling responses in rats with unilateral nigral lesions. 1980

J V Halliwell, and R Kumar

1 Rats with unilateral electrolytic lesions involving both parts of the substantia nigra show dose-related, ipsilateral circling responses to apomorphine which are stable over time. 2 In non-tolerant rats, morphine (up to 10 mg/kg) does not elicit any circling behaviour but as tolerance develops to morphine, initially 10 mg/kg daily and then 100 ng/kg daily for about 4 months, the rats show a progressive tendency to walk more towards the side of the lesion. This behaviour is qualitatively different from apomorphine-induced circling. 3 When apomorphine (0 to 1.0 mg/kg) and morphine (10 or 100 mg/kg) are tested together, the total amounts of 'circling' are increased in an additive manner. However, after 22 h withdrawal from morphine there is a more marked increase in apomorphine-induced circling which is related to the level of dependence. 4 It is suggested that the sensitivity of striatal dopamine receptors is not altered by morphine dependence and that the increased response to apomorphine in abstinence probably reflects changes in the modulating actions of other neurotransmitter systems in the striatum.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009020	Morphine	The principal alkaloid in opium and the prototype opiate analgesic and narcotic. Morphine has widespread effects in the central nervous system and on smooth muscle.	Morphine Sulfate,Duramorph,MS Contin,Morphia,Morphine Chloride,Morphine Sulfate (2:1), Anhydrous,Morphine Sulfate (2:1), Pentahydrate,Oramorph SR,SDZ 202-250,SDZ202-250,Chloride, Morphine,Contin, MS,SDZ 202 250,SDZ 202250,SDZ202 250,SDZ202250,Sulfate, Morphine
D009021	Morphine Dependence	Strong dependence, both physiological and emotional, upon morphine.	Morphine Abuse,Morphine Addiction,Abuse, Morphine,Addiction, Morphine,Dependence, Morphine
D009043	Motor Activity	Body movements of a human or an animal as a behavioral phenomenon.	Activities, Motor,Activity, Motor,Motor Activities
D011954	Receptors, Dopamine	Cell-surface proteins that bind dopamine with high affinity and trigger intracellular changes influencing the behavior of cells.	Dopamine Receptors,Dopamine Receptor,Receptor, Dopamine
D011957	Receptors, Opioid	Cell membrane proteins that bind opioids and trigger intracellular changes which influence the behavior of cells. The endogenous ligands for opioid receptors in mammals include three families of peptides, the enkephalins, endorphins, and dynorphins. The receptor classes include mu, delta, and kappa receptors. Sigma receptors bind several psychoactive substances, including certain opioids, but their endogenous ligands are not known.	Endorphin Receptors,Enkephalin Receptors,Narcotic Receptors,Opioid Receptors,Receptors, Endorphin,Receptors, Enkephalin,Receptors, Narcotic,Receptors, Opiate,Endorphin Receptor,Enkephalin Receptor,Normorphine Receptors,Opiate Receptor,Opiate Receptors,Opioid Receptor,Receptors, Normorphine,Receptors, beta-Endorphin,beta-Endorphin Receptor,Receptor, Endorphin,Receptor, Enkephalin,Receptor, Opiate,Receptor, Opioid,Receptor, beta-Endorphin,Receptors, beta Endorphin,beta Endorphin Receptor,beta-Endorphin Receptors
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
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
D001058	Apomorphine	A derivative of morphine that is a dopamine D2 agonist. It is a powerful emetic and has been used for that effect in acute poisoning. It has also been used in the diagnosis and treatment of parkinsonism, but its adverse effects limit its use.	Apokinon,Apomorphin-Teclapharm,Apomorphine Chloride,Apomorphine Hydrochloride,Apomorphine Hydrochloride Anhydrous,Apomorphine Hydrochloride, Anhydrous,Apomorphine Hydrochloride, Hemihydrate,Britaject,Apomorphin Teclapharm