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.

[1]  C. Hug,et al.  The Anesthetic Potency of Fentanyl in Terms of Its Reduction of Enflurane MAC , 1982, Anesthesiology.

[2]  C. Hug,et al.  The Enflurane Sparing Effect of Morphine, Butorphanol, and Nalbuphine , 1982, Anesthesiology.

[3]  T. Gal,et al.  Analgesic and Respiratory Depressant Activity of Nalbuphine: A Comparison with Morphine , 1982, Anesthesiology.

[4]  R. Rothman,et al.  Mu and delta receptors: their role in analgesia in the differential effects of opioid peptides on analgesia. , 1982, Life sciences.

[5]  C. Difazio,et al.  Anesthetic Potency of Nalbuphine and Interaction with Morphine in Rats , 1981, Anesthesia and analgesia.

[6]  E. Gepts,et al.  Analgesic properties of dezocine for relief of postoperative pain. , 1979, Acta anaesthesiologica Belgica.

[7]  R. Fragen,et al.  Comparison of dezocine (WY 16, 225) and meperidine as postoperative analgesics. , 1978, Anesthesia and analgesia.

[8]  W. Martin,et al.  The effects of morphine and nalorphine-like drugs in the nondependent, morphine-dependent and cyclazocine-dependent chronic spinal dog. , 1976, The Journal of pharmacology and experimental therapeutics.

[9]  M. I. Gluckman,et al.  Animal pharmacology of Wy-16,225, a new analgesic agent. , 1975, The Journal of pharmacology and experimental therapeutics.

[10]  S. Jennett,et al.  Respiratory depression following single and repeated doses of pentazocine and pethidine. , 1972, British journal of anaesthesia.

[11]  C. Difazio,et al.  The anesthesia-sparing effect of pentazocine, meperidine, and morphine. , 1970, Archives internationales de pharmacodynamie et de therapie.