Chloride ion channels are associated with adherence of lymphatic endothelial cells

We have examined the role of chloride ion channels as part of the control mechanism for adherence and growth of lymphatic endothelial cells. The chloride channel inhibitor N-phenylanthranilic acid (0.1 mM) inhibited the initial adherence of previously nonadherent cells in the period up to 3 hr following seeding onto gelatin-coated culture dishes. The potassium channel inhibitor 4-aminopyridine (1 mM) had no effect on the rate of cell adherence. N-Phenylanthranilic acid had no effect when added to confluent monolayers of cells that had been growing for 3 days. This, and the observation that N-phenylanthranilic acid did not affect the ultrastructure of the cells, suggested that plasma membrane chloride channels are involved in the initial signaling cascade triggered when lymphatic endothelial cells begin to adhere to a substrate.