Biomaterial Database

Abuse liability of the anesthetic propofol: self-administration of propofol in rats under fixed-ratio schedules of drug delivery. 2000

M G LeSage, and D Stafford, and J R Glowa

Department of Pharmacology and Therapeutics, Louisiana State University Medical Center, Shreveport, 1501 Kings Highway, Shreveport, LA 71130-3932, USA.

BACKGROUND Previous reports suggest that propofol (PPF) may have abuse potential in humans. Hence, we hypothesized that PPF could reinforce self-administration behavior in other species. Positive reinforcing effects of PPF could be interpreted as an index of abuse liability. OBJECTIVE Acquisition and maintenance of i.v. PPF self-administration were examined in 12 rats. METHODS Six rats were initially given access to methohexital (MHX, 2.0 mg/kg per infusion) under a fixed ratio (FR) 1 schedule, while the other six were initially given access to PPF (1.7 mg/kg per infusion). Once stable responding was established, various doses of PPF (0.56, 1.0, and 1.7 mg/kg per infusion) and vehicle (Intralipid 20%) were made available. RESULTS The number of PPF infusions per session was an inverse function of dose, with 0.56 mg/kg and 1.0 mg/kg per infusion maintaining significantly more infusions per session than vehicle in most rats under the FR 1 schedule. For some rats, the number of vehicle infusions per session was equal to or greater than the number of PPF infusions. Increasing the response requirement to FR 5 decreased the number of vehicle infusions per session in these rats, while PPF maintained a higher number of infusions than vehicle under this FR value in six of seven rats. CONCLUSIONS PPF served as a reinforcer in rats under FR schedules of i.v. drug delivery, adding to the extant evidence that it has abuse potential.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008723	Methohexital	An intravenous anesthetic with a short duration of action that may be used for induction of anesthesia.	Methohexitone,Brevimytal Natrium,Brevital,Brietal,Brietal-Sodium,Methohexital Sodium,Methohexital, Monosodium Salt,Brietal Sodium,Monosodium Salt Methohexital,Natrium, Brevimytal,Sodium, Methohexital
D012055	Reinforcement Schedule	A schedule prescribing when the subject is to be reinforced or rewarded in terms of temporal interval in psychological experiments. The schedule may be continuous or intermittent.	Reinforcement Schedules,Schedule, Reinforcement,Schedules, Reinforcement
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
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
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
D015742	Propofol	An intravenous anesthetic agent which has the advantage of a very rapid onset after infusion or bolus injection plus a very short recovery period of a couple of minutes. (From Smith and Reynard, Textbook of Pharmacology, 1992, 1st ed, p206). Propofol has been used as ANTICONVULSANTS and ANTIEMETICS.	Disoprofol,2,6-Bis(1-methylethyl)phenol,2,6-Diisopropylphenol,Aquafol,Diprivan,Disoprivan,Fresofol,ICI-35,868,ICI-35868,Ivofol,Propofol Abbott,Propofol Fresenius,Propofol MCT,Propofol Rovi,Propofol-Lipuro,Recofol,2,6 Diisopropylphenol,ICI 35,868,ICI 35868,ICI35,868,ICI35868
D017208	Rats, Wistar	A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.	Wistar Rat,Rat, Wistar,Wistar Rats
D051381	Rats	The common name for the genus Rattus.	Rattus,Rats, Laboratory,Rats, Norway,Rattus norvegicus,Laboratory Rat,Laboratory Rats,Norway Rat,Norway Rats,Rat,Rat, Laboratory,Rat, Norway,norvegicus, Rattus
D018686	Anesthetics, Intravenous	Ultrashort-acting anesthetics that are used for induction. Loss of consciousness is rapid and induction is pleasant, but there is no muscle relaxation and reflexes frequently are not reduced adequately. Repeated administration results in accumulation and prolongs the recovery time. Since these agents have little if any analgesic activity, they are seldom used alone except in brief minor procedures. (From AMA Drug Evaluations Annual, 1994, p174)	Intravenous Anesthetic,Intravenous Anesthetics,Anesthetic, Intravenous