Continuous co-administration of dextromethorphan or MK-801 with morphine: attenuation of morphine dependence and naloxone-reversible attenuation of morphine …
N-Methyl-d-aspartate (NMDA) receptor antagonists have been repeatedly shown to
attenuate the development of opiate tolerance and dependence in rodents. In the present
experiments, continuous subcutaneous infusion of either MK-801 (0.01 mg/kg/h but not
0.005 mg/kg/h) or DM (0.133, 0.67 and 1.33 mg/kg/h) reliably prolonged the antinociceptive
effect of continuous subcutaneous infusion of morphine sulfate (2.0 mg/kg/h), indicating
attenuation of the development of morphine tolerance. Furthermore, this prolonged …
attenuate the development of opiate tolerance and dependence in rodents. In the present
experiments, continuous subcutaneous infusion of either MK-801 (0.01 mg/kg/h but not
0.005 mg/kg/h) or DM (0.133, 0.67 and 1.33 mg/kg/h) reliably prolonged the antinociceptive
effect of continuous subcutaneous infusion of morphine sulfate (2.0 mg/kg/h), indicating
attenuation of the development of morphine tolerance. Furthermore, this prolonged …