Effects of forced walking stress on formalin-induced paw licking in mice.
This study examined the effects of exposing mice to forced walking stress on formalin-induced paw licking. At each observation period (0.5-6 h) after exposure to forced walking stress, a significant antinociceptive effect (stress-induced analgesia, SIA) was observed only in the second phase (from 10 to 30 min), but not in the first phase (from 0 to 10 min) of formalin-induced paw licking in mice. The present data showed that SIA induced by exposure to forced walking stress was dependent on duration of the stress (0.5-4 h). SIA was dose-dependently antagonized by the NMDA receptor antagonist dizocilipine (0.01-0.04 mg/kg) but not by naloxone (10 mg/kg). Thus, the present results suggest that exposure to forced walking stress could cause SIA which may be involved in the nonopioid system via NMDA receptors.
Sakurada
S
S
Department of Physiology and Anatomy, Tohoku Pharmaceutical University, Sendai, Japan. s-sakura@tohoku-pharm.ac.jp
Onodera
K
K
Katsuyama
S
S
Yonezawa
A
A
Arai
K
K
Hayashi
T
T
Furuta
S
S
Sato
T
T
Kisara
K
K
D000698:Analgesia; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology*; D016291:Dizocilpine Maleate / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005557:Formaldehyde; D008297:Male; D051379:Mice; D009270:Naloxone / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D018696:Neuroprotective Agents / Q000494:pharmacology; D010146:Pain / Q000503:physiopathology*; D010147:Pain Measurement; D005082:Physical Exertion; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors; D013312:Stress, Physiological / Q000503:physiopathology*; D016138:Walking
D018691:Excitatory Amino Acid Antagonists; D009292:Narcotic Antagonists; D018696:Neuroprotective Agents; D016194:Receptors, N-Methyl-D-Aspartate; D005557:Formaldehyde; D009270:Naloxone; D016291:Dizocilpine Maleate