在将具有CNTF梯度的Gel-Ma微管介入兔子视神经前，先将视网膜外植体铺到不同的Gel-Ma膜上在体外培养，再用βⅢ tubulin 特异性染RGCs，在体外评价了CNTF梯度对RGCs轴突的诱导效应。

Before inserting Gel-Ma microtubules with CNTF gradient into the optic nerve of rabbits, the retinal explants were spread on different Gel-Ma membranes and cultured in vitro, and then RGCs were specifically stained with βⅢ tubulin. The CNTF gradient was evaluated in vitro Inducing effect on RGCs axons.