Tang Ning, Ong Wei-Yi, Yeo Jin-Fei, Farooqui Akhlaq A
Department of Oral and Maxillofacial Surgery, National University of Singapore.
J Orofac Pain. 2009 Spring;23(2):167-73.
To evaluate possible effects of the intracerebroventricular (icv) injection of either O-Tricyclo [5.2.1.0(2,6)] dec-9-yl dithiocarbonate potassium salt (D609), a potent antioxidant and inhibitor of phosphatidylcholine specific phospholipase C (PtdCho-PLC) and acid sphingomyelinase (ASMase), or the spin trap/free radical scavenger N-tert-Butyl-alpha-phenylnitrone (PBN), on mechanical allodynia induced by facial carrageenan injection in mice.
Balb/c mice received icy injection of D609/PBN plus facial carrageenan injection, and the number of face wash strokes to von Frey hair mechanical stimulation of the maxillary skin was quantified. PtdCho-PLC and ASMase activities were also assayed in the brainstem, thalamus, and somatosensory cortex.
Mice that received the icy injection of 10 nmol D609 plus facial carrageenan injection showed significantly fewer face wash strokes evoked by von Frey hair stimulation (indicating reduced mechanical allodynia) at 1 and 3 days post-injection, compared to mice that received icy injection of isotonic saline plus facial carrageenan injection. Mice that received icy injection of 1.13 micromol PBN plus facial carrageenan injection likewise showed significantly fewer face wash strokes after facial carrageenan injection, compared to isotonic saline-injected plus carrageenan-injected controls. D609 injection also resulted in significantly reduced ASMase activity in the brainstem, thalamus, and somatosensory cortex 3 days after injection, compared to controls.
The icv injections of D609 and PBN were effective in reducing mechanical allodynia after facial carrageenan injection-induced pain. Together, the results point to a possible role of central nervous system sphingolipids and/or free radicals in orofacial pain.
评估脑室内（icv）注射O - 三环[5.2.1.0(2,6)]癸 - 9 - 基二硫代碳酸钾盐（D609，一种有效的抗氧化剂及磷脂酰胆碱特异性磷脂酶C（PtdCho - PLC）和酸性鞘磷脂酶（ASMase）的抑制剂）或自旋捕获/自由基清除剂N - 叔丁基 - α - 苯基硝酮（PBN）对小鼠面部注射角叉菜胶诱导的机械性异常性疼痛的可能影响。
Balb/c小鼠接受icv注射D609/PBN加上面部注射角叉菜胶，并对面部上颌皮肤接受von Frey毛发机械刺激时的洗脸次数进行量化。还对脑干、丘脑和体感皮层中的PtdCho - PLC和ASMase活性进行了测定。
与接受icv注射等渗盐水加面部注射角叉菜胶的小鼠相比，接受icv注射10 nmol D609加面部注射角叉菜胶的小鼠在注射后1天和3天，由von Frey毛发刺激引起的洗脸次数显著减少（表明机械性异常性疼痛减轻）。与注射等渗盐水加角叉菜胶的对照组相比，接受icv注射1.13 μmol PBN加面部注射角叉菜胶的小鼠在面部注射角叉菜胶后同样显示出显著减少的洗脸次数。与对照组相比，注射D609后3天，脑干、丘脑和体感皮层中的ASMase活性也显著降低。
icv注射D609和PBN可有效减轻面部注射角叉菜胶诱导的疼痛后的机械性异常性疼痛。总之，结果表明中枢神经系统鞘脂和/或自由基在口面部疼痛中可能起作用。
