Anesthetic potency of dezocine and its interaction with morphine in rats.
A new partial agonist-antagonist analgesic drug, dezocine, was evaluated in rats for its anesthetic potency using a MAC-reduction model. Respiratory effects as shown by changes in PaCO2 were also analyzed. A reduction of approximately 50% in cyclopropane MAC was found with doses of 6 mg/kg or more. This is the largest reduction for any drug of this class. PaCO2 levels increased up to 52 mm Hg with doses of dezocine up to 2 mg/kg. No evidence of reversal of respiratory depression or of further respiratory depression was found with increasing dosages. Combining dezocine with morphine resulted in a further reduction in cyclopropane MAC without a significant change in PaCO2. This suggests that dezocine acts primarily on the same receptor (mu) as morphine and that this receptor activity is further modulated by effects of dezocine on a second opioid receptor.
D000777:Anesthetics; D000818:Animals; D019086:Bridged Bicyclo Compounds, Heterocyclic; D002245:Carbon Dioxide / Q000097:blood; D003516:Cycloparaffins / Q000494:pharmacology*; D003521:Cyclopropanes; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D009020:Morphine / Q000494:pharmacology*; D010313:Partial Pressure; D051381:Rats; D011919:Rats, Inbred Strains; D012119:Respiration / Q000187:drug effects; D013764:Tetrahydronaphthalenes
D000777:Anesthetics; D019086:Bridged Bicyclo Compounds, Heterocyclic; D003516:Cycloparaffins; D003521:Cyclopropanes; D013764:Tetrahydronaphthalenes; D002245:Carbon Dioxide; D009020:Morphine; C030797:cyclopropane; C010827:dezocine