外周炎症性疼痛刺激诱导丘脑中胶质细胞激活及细胞因子的表达

Glial activation and proinflammatory cytokine expression in the thalamus induced by peripheral inflammatory pain

目的:研究完全弗氏佐剂(CFA)外周刺激后,大鼠丘脑中线核群和板内核群中星形胶质细胞标记物(GFAP)、小胶质细胞标记物(Iba)以及细胞因子(IL-1β,TNF-α)的表达变化。方法:逆转录聚合酶链式反应(RT-PCR),免疫印迹法,免疫组织化学。结果:在炎症刺激后的4 h、3 d和14 d,丘脑中线核群和板内核群中小胶质细胞的标记物CD14、细胞因子IL-1β,TNF-α的mRNA和蛋白均有增加;星形胶质细胞标记物GFAP在炎症后的3 d和14 d,其mRNA和蛋白有显著增加。结论:外周炎症性刺激能够相继激活丘脑中线核群和板内核群的小胶质细胞和星形胶质细胞,并使炎症前细胞因子表达增多。提示该部位的胶质细胞可能通过细胞因子参与对炎症性疼痛的调节。

Objective： To observe the activation of astrocytes and microglia, and the expression of proinflammatory cytokines in the midline and intralaminar thalamic nuclei by complete Freunds adjuvant （CFA）-induced inflammatory pain in rats. Methods： Reverse transcription polymerase chain reaction （RT PCR）, Western blot, and immunohistochemistry were used in this study. Results： The mRNA and protein of microglial marker （cluster of differentiation 14, CD14） and proinflammatory cytokines （interleukin-1β, tumor necrosis factor-α showed a significant increase at 4 h, 3 d and 14 d after peripheral inflammatory stimulation. Astroglial marker （GFAP） mRNA and protein were increased only at day 3 and day 14 after inflammation. Conclusion： Peripheral inflammation could induce the activation of microglia and astrocytes subsequently, as well as the increase of proinflammatory cytokines. The results suggest that glial cells in the midline and intralaminar thalamic nuclei were involved in the modulation of pain by proinflammatory cytokines.