大鼠脊髓背角向丘脑和外侧臂旁核的神经降压素能投射

本研究应用荧光金(FG)逆行追踪结合神经降压素(NT)免疫荧光组织化学染色的双标记技术,观察了大鼠脊髓背角向丘脑(TH)和外侧臂旁核(LPb)的NT能投射。将FG注入一侧TH或LPb后,FG逆标神经元主要见于脊髓背角的I层;NT阳性神经元主要分布于脊髓背角的I层、II层外侧部及II层内侧部与III层交界处;脊髓背角I层内可观察到FG逆标记并呈NT阳性的双标记神经元。上述结果表明脊髓背角I层的NT阳性神经元向TH和LPb投射,提示脊髓背角I层内的NT阳性神经元可能向TH和LPb传递伤害性信息。

NEUROTENSINERGIC PROJECTION FROM THE SPINAL DORSAL HORN TO THE THALAMUS AND LATERAL PARABRACHIAL NUCLEUS IN THE RAT

Employing fluoro-gold (FG) retrograde tracing combined with immunofluorescence histochemical staining for neurotensin (NT), we examined the neurotensinergic projection from the spinal dorsal horn to the thalamus (TH) or lateral parabrachial nucleus (LPb) in the rat. After injecting FG into unilateral TH or LPb, FG retrogradely labeled neurons were observed mainly in lamina I of the spinal dorsal horn. NT immunopositive neurons were observed in lamina I, the outer part of lamina II and the border region between inner part of lamina II and lamina III. Some FG-labeled neurons in lamina I of the spinal dorsal horn also exhibited NT immunoreactivity. The present results indicate that NT immunopositive neurons in the lamina I of spinal dorsal horn project to the TH and LPb, suggesting that NT immunopositive neurons in lamina I of the spinal dorsal horn might transmit nociceptive information from the spinal dorsal horn to the TH and LPb.