Presence of opioid growth factor and its receptor in the normal dog, cat and horse cornea.

The research paper investigates if the opioid growth factor (OGF) and its specific receptor (OGFr) are present in the healthy cornea of cats, dogs, and horses.

Research Methods

• Corneas for the study were acquired from cats, dogs, and horses that were euthanized for reasons unconnected to this research. The study involved one cornea each from three different species: cats, dogs, and horses. Each cornea was chosen randomly, either from the left or right eye of each animal.
• The corneas were then harvested, stored in a specific corneal storage medium, and transported to the M.S. Hershey Medical Center of The Pennsylvania State University.
• The researchers applied immunocytochemistry techniques to reveal the presence and location of OGF and OGFr. The tissues were rinsed in Sorenson’s phosphate buffer, steeped in 20% sucrose and buffer, then snap frozen in isopentane.
• The corneas were subsequently embedded in OCT medium and 15-micrometer cryostat sections were produced.
• The method to determine the presence of OGF involved the use of a polyclonal antibody to [Met5]enkephalin and analyzing the immunoreactivity. Similarly, the presence of OGFr was determined using a previously characterized rabbit polyclonal antibody to the receptor.

Results and Conclusion

• The results showed that significant amounts of OGF and OGFr were identified in the corneal epithelium of all three species.
• The conclusion drawn from the research is that the opioid growth factor and its specific receptor are indeed present in the epithelium of normal corneas of cats, dogs, and horses.
• The study goes onto suggest a theory that the presence of OGF in the cornea of many species could potentially inhibit the healing of injured tissue.