School of Aeronautic Science and Engineering, Beihang University, Beijing, China.
Neuroimmunomodulation. 2012;19(4):235-40. doi: 10.1159/000335167. Epub 2012 Mar 21.
It has been shown that interferon-α (IFN-α) is synthesized and secreted by macrophages, monocytes, T lymphocytes, glial cells and neurons. IFN-α has been shown to have an antinociceptive effect at the supraspinal level in the nerve system. However, it is unclear how IFN-α is involved in the modulation of nociceptive transmission in the spinal cord.
In the present study, IFN-α was used to test the potential functional roles in the nociceptive transmission. Using the whole-cell patch-clamp technique, we examined the effects of IFN-α on substantia gelatinosa (SG) neurons in the dorsal root-attached spinal cord slice prepared from adult rats.
We found that IFN-α increased glutamatergic excitatory postsynaptic currents evoked by the stimulation of either Aδ or C afferent fibers. Further studies showed that IFN-α treatment dose-dependently increased spontaneous excitatory postsynaptic current frequency in SG neurons, while not affecting the amplitude. Moreover, intrathecal antibody of IFN-α could reduce nociceptive responses in formalin test.
These results suggest that IFN-α presynaptically facilitates the excitatory synaptic transmission to SG neurons. The nociceptive responses could be inhibited by IFN-α antibody in the formalin test. Thus, IFN-α enhances the nociceptive transmission, which contributes to the behavioral nociceptive responses.
已经证明干扰素-α（IFN-α）由巨噬细胞、单核细胞、T 淋巴细胞、神经胶质细胞和神经元合成和分泌。IFN-α已被证明在神经系统的脊髓以上水平具有镇痛作用。然而，IFN-α 如何参与脊髓中伤害性传递的调制尚不清楚。
在本研究中，使用 IFN-α 来测试其在伤害性传递中的潜在功能作用。使用全细胞膜片钳技术，我们检查了 IFN-α 对成年大鼠背根附着脊髓切片中胶状质（SG）神经元的影响。
我们发现 IFN-α 增加了由 Aδ或 C 传入纤维刺激引起的谷氨酸能兴奋性突触后电流。进一步的研究表明，IFN-α 处理剂量依赖性地增加了 SG 神经元中自发性兴奋性突触后电流的频率，而不影响其幅度。此外，鞘内注射 IFN-α 抗体可减少福尔马林试验中的伤害性反应。
这些结果表明，IFN-α 在前突触促进了 SG 神经元的兴奋性突触传递。福尔马林试验中的 IFN-α 抗体可抑制伤害性反应。因此，IFN-α 增强了伤害性传递，有助于行为性疼痛反应。
