Sonic Hedgehog及其受体Patched在小鼠视交叉发育过程中的表达

在小鼠胚胎发育过程中,胚胎第13d(E13)至15d(E15)是视交叉发育的主要阶段。在本研究中,我们观察了在E13～E15,Sonic Hedgehog(Shh)及其受体Patched(Ptc)在视觉传导通路的表达。结果发现:在视交叉和视束中,Shh在视神经纤维接近中线时表达上调,越过中线后表达下调,并且主要表达在较深的区域。Ptc在E13～E14的视网膜和E14～E15的视束中有表达,但在视交叉中无表达。Ptc,而不是Shh,表达在体外培养的生长锥中。Shh和Ptc在视觉传导通路发育中的表达提示Shh可能在引导视神经生长方面发挥一定作用。

EXPRESSION OF SONIC HEDGEHOG AND ITS RECEPTOR PATCHED DURING DEVELOPMENT OF MOUSE OPTIC CHIASM

E13-E15 was the major period of development of retinofugal pathway during the development of mouse embryos. In this study, we observed the expression of Sonic Hedgehog (Shh), an embryonic protein and its receptor, Patched (Ptc) in E13-E15 in the chiasm in mouse embryos. Results showed that Shh was expressed in deeper region of chiasm and optic tract. Shh expression was upregulated when axons approached the midline and downregulated after axon crossed the midline. Ptc was expressed in the optic stalk and optic tract, but not in the chiasm. Ptc, not Shh was expressed in growth cones in retinal explant culture. The changes of expression of Shh and Ptc in the chiasm suggest that Shh might play a signaling function during the development of retinalfugal pathway.