Mygalin, a diacylspermidine that is naturally found in the hemolymph of the spider Acanthoscurria gomesiana, is of interest for development as a potential analgesic. Previous studies have shown that acylpolyamines modulate glutamatergic receptors with the potential to alter pain pathways. This study aimed to evaluate the effects of mygalin on acute and chronic pain in rodents. For evaluation of acute pain, Wistar rats were subjected to tail-flick and hot-plate nociceptive tests. For the evaluation of chronic neuropathic pain, a partial ligation of the sciatic nerve was performed and, 21 days later, animals were examined in hot-plate, tail-flick, acetone, and von Frey tests. Either Mygalin or vehicle was microinjected in the dorsal raphe nucleus (DRN) before the tests. Another group was pretreated with selective antagonists of glutamate receptors (LY 235959, MK-801, CNQX, and NBQX). Mygalin decreases nociceptive thresholds on both acute and chronic neuropathic pain models in all the tests performed. The lowest dose of mygalin yielded the most effective nociception, showing an increase of 63% of the nociceptive threshold of animals with neuropathic chronic pain. In conclusion, mygalin microinjection in the DRN results in antinociceptive effect in models of neuropathic pain, suggesting that acylpolyamines and their derivatives, such as this diacylspermidine, could be pursued for the treatment of neuropathic pain and development of selective analgesics.

中文翻译：

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Acanthoscurria gomesiana 蜘蛛衍生的中缝背核合成 mygalin 调节急性和慢性疼痛

Mygalin，一种二酰基亚精胺，天然存在于蜘蛛Acanthoscurria gomesiana的血淋巴中, 作为一种潜在的镇痛剂有兴趣开发。先前的研究表明，酰基多胺可以调节谷氨酸受体，并有可能改变疼痛通路。本研究旨在评估 mygalin 对啮齿动物急性和慢性疼痛的影响。为了评估急性疼痛，Wistar 大鼠接受了甩尾和热板伤害性测试。为了评估慢性神经性疼痛，对坐骨神经进行了部分结扎，21 天后，对动物进行了热板、甩尾、丙酮和 von Frey 试验。在测试前，将 Mygalin 或载体显微注射到中缝背核 (DRN) 中。另一组用谷氨酸受体的选择性拮抗剂（LY 235959、MK-801、CNQX 和 NBQX）预处理。在进行的所有测试中，Mygalin 降低了急性和慢性神经性疼痛模型的伤害性阈值。最低剂量的 mygalin 产生最有效的伤害感受，显示神经性慢性疼痛动物的伤害感受阈值增加了 63%。总之，DRN 中的 mygalin 显微注射在神经性疼痛模型中产生镇痛作用，这表明酰基多胺及其衍生物（例如二酰基亚精胺）可用于治疗神经性疼痛和开发选择性镇痛剂。