Protection of the Cornea from UVB Radiation by Elevated Potassium in Tears

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Professor John Ubels works with students studying the effect of UVB radiation on the corneal epithelium of the eye. UVB causes cells to go into apoptosis (programed cell death) due to opening of potassium channels and loss of intracellular potassium. In collaboration with Physics professor Loren Haarsma, he is studying the mechanisms by which potassium channels are activated by UVB and the effects of UVB on intracellular signaling pathways that mediate apoptosis. The overall hypothesis of this research is that the high concentration of potassium in the tears that continually bathe the surface of the eye protects the cornea from damage by UVB by reducing the electrochemical gradient for potassium across the cell membrane, preventing loss of potassium from cells when they are exposed to UVB.


John Ubels

John Ubels

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