Factors regulating oral consumption of an opioid (etonitazene) by morphine-addicted rats

  title={Factors regulating oral consumption of an opioid (etonitazene) by morphine-addicted rats},
  author={Abraham Wikler and W. R. Wayne Martin and Frank T. Pescor and C. G. Eades},
The experiments described in this report constitute par t of a longterm research program on the possible roles of conditioning factors in the genesis of relapse to opioid ~ drug use following apparent recovery from the withdrawal phenomena produced by the addicting (physicaldependence-producing) agent. The general theoretical orientation of this program has been described elsewhere (WIKLE~ 1961) and the results obtained in the conditioning studies will be described in a subsequent report (WIxLE… 

Development of morphine dependence in rats: Lack of effect of previous ingestion of other drugs

Ingestion of alcohol, amylobarbitone, chlordiazepoxide, cocaine or dexamphetamine did not affect the eventual development of dependence when solutions of morphine were substituted at a later stage, although the avoidance of dexamphetamine seemed to temporarily transfer to morphine.

Classical conditioning of a morphine abstinence phenomenon, reinforcement of opioid-drinking behavior and “relapse” in morphine-addicted rats

The pre-potent factor in disposing to relapse, at least in the rat under the experimental conditions described, is the long-term persistence of unconditioned disturbances in homeostasis following with-drawal of morphine which can provide a source of reinforcement for operant conditioning of opioid-seeking behavior during “relapse-testing” sessions even without benefit of previous “training”.

Tolerance to and physical dependence on morphine in rats

The secondary abstinence syndrome of rats addicted to large doses of morphine is protracted and small differences have been seen between addicted and control animals as long as four to six months after withdrawal of morphine.

Persistent potency of a secondary (conditioned) reinforcer following withdrawal of morphine from physically dependent rats

The evidence indicates that the potency of secondary reinforcers so generated can persist long after morphine withdrawal, and some implications for problems of relapse and treatment of opioid addicts are discussed.

Regulation of drug and water intake in rats dependent on morphine

The results support the view that preferences for morphine in rats can provide a valid measure of their need for the drug.

Narcotic blockade, length of addiction and persistence of etonitazene consumption in rats

Animals with a greater history of previous drug exposure developed ETZ preferences more rapidly than did relatively drug-naive animals, and animals with the greatest history of prior addiction continued to drink large quantities of ETZ, despite pretreatment with relatively large doses of naloxone.

Relative potency of codeine, methadone and dihydromorphinone to morphine in self-maintained addict rats

  • R. CollinsJ. Weeks
  • Biology, Psychology
    Naunyn-Schmiedebergs Archiv für experimentelle Pathologie und Pharmakologie
  • 2004
Analgesic activity for codeine was not proportional to its ability to substitute for morphine in addict rats, and the nighttime rate being about one-third greater than the daytime rate.

Self-administration of psychoactive substances by the monkey

In the present study monkeys developed psychological dependence on morphine, codeine, cocaine, d-amphetamine, pentobarbital, ethanol, and caffeine, and all of these drugs except caffeine produced psychotoxicity.

Effects of levo-alpha-acetylmethadol (LAAM) on morphine self-administration in the rat

Analysis of the patterns of lever pressing, morphine self-injections, and sleepawake behavior revealed that daily IG administration of LAAM effectively suppressed morphineSelf-administration, resulting in a gradual return of lever press and morphine intake to pre-LAAM levels.

The effect of MDMA self-administration on MDMA-produced hyperactivity and c-fos expression

Evidence of behavioural sensitisation as a result of repeated MDMA exposure is provided and region-specific changes in c-fos expression suggest an important role of neuroadaptations in the NAc core and the infralimbic cortex as a consequence of MDMA self-administration.



Tolerance to and physical dependence on morphine in rats

The secondary abstinence syndrome of rats addicted to large doses of morphine is protracted and small differences have been seen between addicted and control animals as long as four to six months after withdrawal of morphine.

Drug addiction. I. Addiction by escape training.

Relapse by animals was demonstrated and the importance of the confirmation of the escape training hypothesis was discussed, if this new action reduces the level of withdrawal.

Determination of the oxygen consumption of groups of rats.

The metabolic rate of small laboratory animals may be determined by either open or closed circuit respirometers, with the advantage of permitting the use of pure oxygen, and the direct measurement of the volume of oxygen consumed by the animal.

Über Benzimidazolderivate mit starker analgetischer Wirkung

A number of basically substituted benzimidazoles show a strong analgesic activity in mice, rats, rabbits, and dogs and are quantitatively superior to all analgetics hitherto described.

Synthese basisch substituierter, analgetisch wirksamer Benzimidazol-Derivate

The syntheses of 1-(β-dialkylamino-ethyl)-2-benzyl-5-nitro-benzimidazoles, a new series of powerful analgesics, are described.

Statistical Method in Biological Assay

Statistical Method in Biological AssayBy Dr. D. J. Finney. Pp. xix + 661. (London: Charles Griffin and Co., Ltd., 1952.) 68s. net.

Morphine addiction in rats.

PEscoR: Unpublished observations. Use of a benzimidazole derivative with potent morphine-like properties orally as a presumptive reinforcer in conditioning of drug-seeking behavior in rats (abstract)

  • Fed. ]?roe. 19,
  • 1960