title: Morphine analgesia in tail-flick and formalin pain tests is mediated by different neural systems.
mesh_terms: D000818:Animals; D001933:Brain Stem / Q000187:drug effects* / Q000502:physiology; D005557:Formaldehyde / Q000494:pharmacology*; D008297:Male; D008636:Mesencephalon / Q000187:drug effects; D009020:Morphine / Q000494:pharmacology*; D009115:Muridae; D009433:Neural Inhibition / Q000187:drug effects; D009619:Nociceptors / Q000187:drug effects* / Q000502:physiology; D011903:Raphe Nuclei / Q000187:drug effects / Q000502:physiology; D013116:Spinal Cord / Q000187:drug effects*
chemical_list: D005557:Formaldehyde; D009020:Morphine