title: Prevention of stress-induced analgesia by substance P.
abstract: It has been shown that a variety of stressful procedures, such as immobilization and footshock, can induce a significant degree of analgesia in mice. In addition, it has been shown that for some, but not all, stressful treatments, the analgesic effect is mediated via endogenous opioids. This report describes the effects of substance P, administered systemically, on both opioid-mediated immobilization-induced analgesia and non-opioid footshock-induced analgesia. Substance P completely blocked the opioid-mediated form of stress-induced analgesia while having no effect on the non-opioid form. Exogenous substance P appears to interact with endogenous opioid pain-suppressing systems.
mesh_terms: D000818:Animals; D001143:Arousal / Q000187:drug effects*; D004597:Electroshock; D008297:Male; D009115:Muridae; D009270:Naloxone / Q000494:pharmacology; D009433:Neural Inhibition / Q000187:drug effects*; D009619:Nociceptors / Q000187:drug effects*; D011957:Receptors, Opioid / Q000187:drug effects; D012149:Restraint, Physical; D013373:Substance P / Q000494:pharmacology*
chemical_list: D011957:Receptors, Opioid; D013373:Substance P; D009270:Naloxone