title: Naloxone reversal of morphine analgesia but failure to alter reactivity to pain in the formalin test.
mesh_terms: D000698:Analgesia; D000818:Animals; D005557:Formaldehyde; D008297:Male; D009020:Morphine / Q000037:antagonists & inhibitors*; D009270:Naloxone / Q000494:pharmacology*; D010146:Pain / Q000139:chemically induced / Q000503:physiopathology*; D051381:Rats; D011930:Reaction Time / Q000187:drug effects; D011957:Receptors, Opioid / Q000187:drug effects / Q000502:physiology; D013997:Time Factors
chemical_list: D011957:Receptors, Opioid; D005557:Formaldehyde; D009270:Naloxone; D009020:Morphine