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PubMed · 6468501

Amphetamine-induced analgesia does not involve brain opioids.

F Drago·G Caccamo·G Continella·U Scapagnini
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Abstract

The intrinsic analgesic properties of amphetamine were studied in rats. Subcutaneous injection of amphetamine exerted an additive effect on morphine-induced analgesia in the hot-plate test. Amphetamine itself showed intrinsic analgesic activity in a dose-dependent manner. Administration of naloxone failed to affect the analgesia induced by amphetamine. However, injection of haloperidol totally suppressed the amphetamine-induced change in pain response latency. Both naloxone and haloperidol failed to affect the pain threshold when injected alone, but inhibited morphine-induced analgesia. It is concluded that amphetamine possesses intrinsic analgesic properties which involve catecholamine but not opioid transmission in the brain.

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AmphetamineAnalgesicsAnimalsBrainEndorphinsHaloperidolMaleMorphineNaloxoneRatsRats, Inbred StrainsReaction TimeJournal Article

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F Drago, G Caccamo, G Continella, U Scapagnini. 1984-06-01. Amphetamine-induced analgesia does not involve brain opioids.. https://doi.org/10.1016/0014-2999(84)90168-7

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