Behavioral effects spinal analgesia

As already mentioned, oxidation of C-l methylene of cyclazocine to carbonyl abolishes the antagonist but retains the agonist actions of the parent compound (p. 423). The behavioral and pharmacological effects of the oxidized product ketazocine 26a in the chronic spinal dog were subsequently compared with those of morphine by Martin, and as a result of differences observed, he dubbed the two compounds k- and /a-agonists, respectively.(106) Thus, while morphine induced analgesia, meiosis, bradycardia, hypothermia, and indifference to environmental stimuli, ketazocine produced meiosis, general sedation, and depression of flexor reflexes but did not alter the skin twitch reflex or pulse rates. 

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