Properties of the masticatory muscle piimary afferents from the trigeminal ganglion in the rats

本研究的主要结果如下：（1）逆标肌传入神经元明显多于逆标皮肤传入神经元。(2)在6%的肌肉和44%的皮肤传入中发现α-D-半乳糖特异性凝集素IB 4结合，表明靶特异性差异。(3)通过向咬肌注射完全弗氏佐剂（CFA）诱导肌肉炎症的实验表明，炎症后4天三叉神经节肌传入神经元中CGRP或SP免疫反应阳性神经元的百分比没有显著变化。(4)肌肉炎症导致CGRP和P物质阳性三叉神经节肌肉传入神经元的数量增加CFA注射后12天。这表明，肌肉炎症后的肽能神经元的数量增加，同样从三叉神经组III和IV肌肉传入招募。(5)结果表明，在三叉神经节中，P2 X3受体不仅表达于IB 4神经元，还包括较大的神经元。P2 X3和IB 4表达存在靶特异性差异。此外，它表明，深部组织炎症可以调节表达P2 X3受体的神经元的数量。

The main findings of this research project are as follows:(1) Rerogradely labeled muscle afferent neurons were significantly lager and fewer than retrogradely labeled cutaneous afferent neurons. (2) α-D-galactose specific lectin IB4 binding was found in 6% of muscle and 44% of cutaneous afferents indicating a target specific difference. (3) The experiments inducing muscle inflammation by injecting complete Freund's adjuvant (CFA) to masseter muscle indicate that the percentage of trigeminal ganglion muscle afferent neurons immunoreactive for CGRP or SP does not change significantly four days after inflammation. (4) Muscle inflammation resulted in increased number of CGRP and substance P positive trigeminal ganglion muscle afferent neurons 12 days after CFA injection. It is suggested that the increased number of peptidergic neurons following muscle inflammation is recruited equally from trigeminal group III and IV muscle afferents. (5) It is indicated that in trigeminal ganglia, P2X3 receptor is not exclusively expressed in IB4 neurons but includes larger neurons. Target specific differences exist in P2X3 and IB4 expression. Furthermore, it is suggested that deep tissue inflammation can modulate the number of neurons expressing the P2X3 receptor.