Stimulation of neurite growth by epithelial implants into corneal stroma.

The neuronotrophic action of various ocular tissues to stimulate the ectopic formation of preterminal and terminal neural structures was tested in vivo. Pockets within the collagenous corneal parenchyma were implanted with pieces of epithelium, collagen with and without basal lamina, or conjunctival epithelium. After 3-4 weeks, corneas stained by the gold chloride procedure showed axon terminals within the epithelial cyst and plexiform arrangements at the periphery. In contrast, neither conjunctival epithelium nor collagen showed the ability to stimulate neural growth.