Abstract
The effects of morphine and a potent enkephalin analogue on spontaneous locomotion have been compared in mice. In doses of 3–10 mg/kg SC both compounds induced a brief reduction of motor activity followed by a period of behavioral hyperactivity. Similar receptorial mechanisms are suggested in mediation of their motor effects.
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Miglécz, J.I.S.E., Rónai, A.Z. Biphasic effects of a potent enkephalin analogue (d-Met2,Pro5)-enkephalinamide and morphine on locomotor activity in mice. Psychopharmacology 71, 299–301 (1980). https://doi.org/10.1007/BF00433065
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DOI: https://doi.org/10.1007/BF00433065