[Corneal wound healing in rabbits as affected by substances changing the cyclic nucleotide level]

A rabbit corneal deepthelization model was used to study in vivo the effects of agents changing the level of cyclic nucleotides on the time of its corneal epithelial wound healing. Cholera toxin (CT) and thermostable E.coli toxin (ST toxin) were employed as agents elevating the level of cAMP and cHMP. The studies showed that a healing process in rabbits could be divided into 4 periods, depending on the epithelization rate. CT instilled in doses of 0.25-2.00 micrograms per year reduced the healing of an epithelial defect by 10 hours, increased the epithelization rate 2-fold at hours 4 to 20, but failed to affect in the remaining periods. It is suggested that by elevating the intracellular cAMP level in this period, CT accelerates migration of epithelial cells, while ST toxin increasing the level of cHGP fails to affect the time of corneal wound epithelization. It is concluded that it is promising to search for new drugs for accelerating the healing of corneal wounds among the agents elevating the level of intracellular cAMP.