Effects of valinomycin on lymphocytes independent of potassium permeability.
10(-7) M valinomycin affects human lymphocytes in the following manner: (1) it is non-toxic; (2) it inhibits mitogenesis; (3) it causes a reduction in cell ATP; and (4) it causes a marked increase in steady-state Na+ exchange. However, it has a minimal effect on cell ion (K+, Na+, Ca2+, Mg2+) contents and no effect whatever on K+ exchange. Neither the fast nor the slow fraction of steady-state K+ exchange is affected by 10(-7) M valinomycin. The various reported effects of valinomycin on lymphocyte functions cannot be assumed to be due to changes in plasma membrane K+ permeability. The mechanism of the increase in steady-state Na+ exchange, and whether or not it is related to inhibition of mitogenesis, are unsettled issues.
D000255:Adenosine Triphosphate / Q000097:blood; D000328:Adult; D001693:Biological Transport, Active / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003208:Concanavalin A / Q000494:pharmacology; D004261:DNA Replication / Q000187:drug effects; D006801:Humans; D007700:Kinetics; D008213:Lymphocyte Activation / Q000187:drug effects; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology / Q000502:physiology*; D011188:Potassium / Q000097:blood*; D012964:Sodium / Q000097:blood; D014634:Valinomycin / Q000494:pharmacology*
D003208:Concanavalin A; D014634:Valinomycin; D000255:Adenosine Triphosphate; D012964:Sodium; D011188:Potassium