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ACTH self-administration in rats.

M Jouhaneau-Bowers·J Le Magnen
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Abstract

The ability of rats to learn a lever pressing response reinforced by a contingent intravenous delivery of ACTH 1--24 and 4--10, was investigated. About 60% of the rats tested learned to press the lever for the two analogues that were infused at a rate of 2.08 microgram per second via a chronically implanted intrajugular catheter. Most of the animals exhibited sustained daily self-injections of 250 to 375 microgram of ACTH 1--24 and more variable amounts of ACTH 4--10. Comparisons with the self-administration of saline and altered responses following a change in the concentration of ACTH 1--24 solution indicated a positively reinforcing effect for the neuropeptide. The self-administration of the ACTH 4--10 analogue demonstrates that this reinforcing property of ACTH is not due to its adrenal stimulating activity. Brain targets possibly involved in the self-administration of ACTH are discussed.

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Adrenocorticotropic HormoneAnimalsInjections, IntravenousLearningMaleRatsSelf AdministrationTime FactorsJournal Article

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M Jouhaneau-Bowers, J Le Magnen. 1979. ACTH self-administration in rats.. https://doi.org/10.1016/0091-3057(79)90191-6

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