Department of Integrative Medicine and Neurobiology, Shanghai Medical College, Institute of Acupuncture Research, State Key Laboratory of Medical Neurobiology, Fudan University, 138 Yi-Xue-Yuan Road, Shanghai 200032, China.
Neurosci Lett. 2011 Mar 3;490(3):175-9. doi: 10.1016/j.neulet.2010.12.027. Epub 2010 Dec 21.
In prior studies, models of inflammatory pain were produced through injecting complete Freund's adjuvant (CFA) or capsaicin directly into either the deep somatic tissue or the animal's hind paw. In contrast, bone cancer-induced pain (BCIP) was simulated through injecting tumor cells into the cavity of the femur or the tibia. It has been reported that, due to differences in afferent innervation, the same stimulus to various tissue types might result in differing patterns of pain response. Hence, the aim of this study is to establish a rat model of bone inflammation-induced pain (BIIP) by injecting CFA into the tibial cavity, the same site involved in the BCIP model. The differences in body weight, bone histology, mechanical allodynia, thermal hyperalgesia, and the pain relieving effects of Celebrex on this model of BIIP were evaluated. The results showed that there was evidence of significant inflammation seen in the bone marrow two days after intra-tibial CFA injection, including nuclear condensation and fragmentation, massive neutrophilic granulocytes, and prominent fibrinous exudates. Fourteen days after injection, marked fibrosis of the bone was detected by histological staining. After unilateral CFA injection, behavioral studies showed mechanical allodynia to von Frey hair stimulation, but no thermal hyperalgesia was observed. Celebrex showed significant anti-allodynic effects on the BIIP model. The results demonstrated that CFA is an effective agent for inducing bone inflammation and subsequent pain-related behavior in rat models, and, thus, provides a practical and valuable contrast for BCIP research.
在先前的研究中，通过将完全弗氏佐剂（CFA）或辣椒素直接注射到深部组织或动物的后爪中，产生了炎症性疼痛模型。相比之下，通过将肿瘤细胞注射到股骨或胫骨的腔中，模拟了骨癌引起的疼痛（BCIP）。据报道，由于传入神经支配的差异，对不同组织类型的相同刺激可能导致不同的疼痛反应模式。因此，本研究的目的是通过将 CFA 注射到胫骨腔中来建立骨炎症性疼痛（BIIP）的大鼠模型，该部位与 BCIP 模型相同。评估了体重、骨组织学、机械性痛觉过敏、热痛觉过敏以及 Celebrex 对这种 BIIP 模型的缓解疼痛作用的差异。结果表明，在胫骨内 CFA 注射后两天，骨髓中可见明显的炎症证据，包括核固缩和碎裂、大量嗜中性粒细胞和明显的纤维蛋白渗出物。注射后 14 天，组织学染色显示骨明显纤维化。在单侧 CFA 注射后，行为研究显示 von Frey 毛发刺激引起机械性痛觉过敏，但未观察到热痛觉过敏。Celebrex 对 BIIP 模型表现出明显的抗痛觉过敏作用。结果表明，CFA 是一种在大鼠模型中诱导骨炎症和随后的疼痛相关行为的有效药物，为 BCIP 研究提供了一种实用且有价值的对比。
