Action of naloxone on the interferon-lowering activity of morphine in the mouse.
The serum titer of interferon produced by polyinosinic:polycytidylic acid (poly I:C) was studied in mice following subcutaneous injections of either morphine alone, naloxone alone, morphine and naloxone together, morphine preceded by naloxone, naloxone preceded by morphine, or a sequence of injections of naloxone, morphine, and naloxone again. Poly I:C injected without the other drugs present served as the control. Both morphine and naloxone produced a significant decrease in the ability of the mice to increase the serum titer of interferon in response to poly I:C. Naloxone appeared to function as an antagonist to morphine when administered following the morphine injection, but not when injected before or simultaneously with the opiate. When naloxone was injected both before and following the morphine injection, results were interpreted to indicate the possibility that naloxone could function as both an agonist and antagonist under this condition.
D000818:Animals; D004347:Drug Interactions; D007372:Interferons / Q000097:blood*; D008297:Male; D051379:Mice; D009020:Morphine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D009270:Naloxone / Q000494:pharmacology*; D011066:Poly C / Q000494:pharmacology
D011066:Poly C; D009270:Naloxone; D009020:Morphine; D007372:Interferons