Eye-wiping test: a sensitive animal model for acute trigeminal pain studies.
The possibility of introducing eye-wiping test as a model of acute pain was examined in rat, and it was compared with the well-known hot plate test. One drop of NaCl 5 M was placed into the animal eye, and the number of eye wipes with the ipsilateral forelimb was counted during 30 s. The withdrawal latency in hot plate test was also examined. Afterward, animals were treated with morphine (1, 2, 4, 6, 8 or 10 mg/kg), imipramine (25 mg/kg), sodium salicylate (250 mg/kg) or saline (i.p). After 30 min, the animals were tested again with eye-wiping and hot plate tests. Our results showed that morphine injection dose dependently decreased the number of eye wipes and increased the response latency to hot plate tests. There was a good correlation between the analgesic effects of morphine on responses to both tests, however, morphine produced more pain relief in eye-wiping test. Imipramine significantly decreased the number of eye wipes and increased the response latency to hot plate test, while sodium salicylate and saline injection did not. It may be concluded that the eye-wiping test can be used as a reliable method in trigeminal pain studies, which is sensitive to opioid and tricyclic antidepressant in rat.
Farazifard
Rasoul
R
Neuroscience Research Center, Kerman University of Medical Sciences, Jomhori Islami Blvd, Kerman, PO Box 76175-113, Iran. r_farazi@yahoo.com
Safarpour
Farzaneh
F
Sheibani
Vahid
V
Javan
Mohammad
M
D000701:Analgesics, Opioid / Q000627:therapeutic use; D000818:Animals; D000928:Antidepressive Agents / Q000627:therapeutic use; D001522:Behavior, Animal / Q000187:drug effects*; D003315:Cornea / Q000502:physiology; D003627:Data Interpretation, Statistical; D004195:Disease Models, Animal; D005123:Eye; D007099:Imipramine / Q000627:therapeutic use; D007509:Irritants; D008297:Male; D009020:Morphine / Q000627:therapeutic use; D010146:Pain / Q000188:drug therapy* / Q000209:etiology*; D010147:Pain Measurement / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D011930:Reaction Time / Q000187:drug effects; D012459:Salicylates / Q000627:therapeutic use; D012965:Sodium Chloride; D014277:Trigeminal Neuralgia / Q000188:drug therapy* / Q000209:etiology*
D000701:Analgesics, Opioid; D000928:Antidepressive Agents; D007509:Irritants; D012459:Salicylates; D012965:Sodium Chloride; D009020:Morphine; D007099:Imipramine