Development and pharmacological verification of a new mouse model of central post-stroke pain.
Central post-stroke pain (CPSP) including thalamic pain is one of the most troublesome sequelae that can occur after a cerebrovascular accident. Although the prevalence of CPSP among stroke patients is relatively low, the persistent, often treatment-refractory, painful sensations can be a major problem and decrease the affected patient's quality of life. To better understand of the pathophysiological basis of CPSP, we developed and characterized a new mouse model of thalamic CPSP. This model is based on a hemorrhagic stroke lesion with collagenase in the ventral posterolateral nucleus of the thalamus. Histopathological analysis indicated that the thalamic hemorrhage produced a relatively confined lesion that destroys the tissue within the initial bleed, and also showed the presence of activated microglia adjacent to the core of hemorrhagic lesions. Behavioral analysis demonstrated that the animals displayed diclofenac-, morphine- or pregabalin-resistant mechanical allodynia and thermal hyperalgesia of the hind paw contralateral to the lesion for over 112 days. However, we found that minocycline, a microglial inhibitor, significantly ameliorated mechanical allodynia and thermal hyperalgesia. These results suggest that this model might be proved as a useful animal model for studying the neuropathology of thalamic syndrome, and developing improved therapeutics for CPSP.
Department of Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan; Department of Neurosurgery, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan.
Tomoko
T
Hanada
Department of Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan. Electronic address: tkmphm10@m.kufm.kagoshima-u.ac.jp.
Takashi
T
Kurihara
Department of Neurosurgery, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan.
Mai
M
Tokudome
Department of Neurosurgery, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan.
Hiroshi
H
Tokimura
Department of Neurosurgery, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan.
Kazunori
K
Arita
Department of Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan.
Atsuro
A
Miyata
D018712:Analgesics, Non-Narcotic / Q000494:pharmacology; D000818:Animals; D002543:Cerebral Hemorrhage / Q000139:chemically induced / Q000150:complications*; D017364:Collagenases; D004195:Disease Models, Animal; D006930:Hyperalgesia / Q000503:physiopathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008911:Minocycline / Q000494:pharmacology; D059226:Nociceptive Pain / Q000209:etiology*; D017288:Pain Threshold / Q000187:drug effects; D020521:Stroke / Q000150:complications*; D013786:Thalamic Diseases / Q000139:chemically induced / Q000150:complications*; D020651:Ventral Thalamic Nuclei / Q000187:drug effects
D018712:Analgesics, Non-Narcotic; D017364:Collagenases; D008911:Minocycline
Allodynia; Chronic pain; Hyperalgesia; Intracerebral hemorrhage; Microglia; Minocycline; Thalamic pain