Voltage- and Ca 2+ -Dependent Chloride Current Activated by Hyposmotic and Hyperosmotic Stress in Rabbit Superior Lacrimal Acinar Cells

Tears provide a protective and lubricating film that covers the anterior surface of the eye. The bulk of tears is a salty serous fluid, containing a variety of proteins associated with bacterial defense. In rabbits, tears are produced by the superior and inferior lacrimal glands. Secretion of the serous fluid is dependent on the distribution and nature of ion channels in lacrimal acinar cells.1,2 We have identified a voltage- and Ca2+-dependent outwardly rectifying Cl- (Clor) channel in rabbit superior lacrimal gland acinar cells. The purpose of this study was to evaluate the role of this Clor channel in secretion by the rabbit lacrimal glan dacinar cells.