Fibromyalgia is characterized by the amplification of central nervous system pain with concomitant fatigue, sleep, mood disorders, depression, and anxiety. It needs extensive pharmacological therapy. In the present study, Swiss mice were treated with reserpine (0.25 mg/kg, s.c.) over three consecutive days, in order to reproduce the pathogenic process of fibromyalgia. On day 4, the administrations of the Tx3-3 toxin produced significant antinociception in the mechanical allodynia (87.16% ±12.7%) and thermal hyperalgesia (49.46% ± 10.6%) tests when compared with the PBS group. The effects produced by the classical analgesics (duloxetine 30 mg/kg, pramipexole 1 mg/kg, and pregabalin 30 mg/kg, p.o., respectively) in both of the tests also demonstrated antinociception. The administrations were able to increase the levels of the biogenic amines (5-HTP and DE) in the brain. The treatments with pramipexole and pregabalin, but not duloxetine, decreased the immobility time in the FM-induced animals that were submitted to the forced swimming test; however, the Tx3-3 toxin (87.45% ± 4.3%) showed better results. Taken together, the data has provided novel evidence of the ability of the Tx3-3 toxin to reduce painful and depressive symptoms, indicating that it may have significant potential in the treatment of FM.

中文翻译：

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Phoneutria nigriventer Tx3-3 肽毒素可减轻小鼠的纤维肌痛症状

纤维肌痛的特点是中枢神经系统疼痛加剧，伴有疲劳、睡眠、情绪障碍、抑郁和焦虑。它需要广泛的药物治疗。在本研究中，瑞士小鼠连续三天接受利血平 (0.25 mg/kg, sc) 治疗，以重现纤维肌痛的致病过程。在第 4 天，与 PBS 组相比，Tx3-3 毒素的给药在机械异常性疼痛 (87.16% ±12.7%) 和热痛觉过敏 (49.46% ± 10.6%) 测试中产生了显着的镇痛作用。经典镇痛药（度洛西汀 30 毫克/千克、普拉克索 1 毫克/千克和普瑞巴林 30 毫克/千克，口服）在这两个测试中产生的作用也证明了镇痛作用。给药能够增加大脑中生物胺（5-HTP 和 DE）的水平。用普拉克索和普瑞巴林而不是度洛西汀进行治疗，减少了进行强迫游泳试验的 FM 诱导动物的不动时间；然而，Tx3-3 毒素 (87.45% ± 4.3%) 表现出更好的结果。总之，这些数据提供了 Tx3-3 毒素减轻疼痛和抑郁症状能力的新证据，表明它在治疗 FM 方面可能具有重大潜力。