title: Calcium dependence of ionophore A23187-induced lymphocyte cytotoxicity.
abstract: Concentrations of the divalent cation ionophore, A23187, optimal for the transformation of human and pig lymphocytes, were cytotoxic to lymphocytes from rats and mice. The biochemical effects associated with A23187-induced cytolysis in rat thymocytes included inhibition of [3H]uridine uptake and incorporation into macromolecules and stimulation of [14C]-alpha-aminoisobutyric acid uptake. The biochemical effects, as well as the reduction in the number of viable cells, were dose dependent and were blocked by the omission of ionic calcium from the incubation medium. At a given ionophore concentration, the magnitude of lysis of thymocytes was proportional to the concentration of Ca2+ in the extracellular medium. Sr2+ was less effective than was Ca2+ in supporting A23187-induced thymocyte lysis. A comparison of the lytic response of lymphocytes of various origins showed that extracellular Ca2+ plays a role in ionophore-induced cytolysis in thymocytes and lymph node lymphocytes but not in mouse lymphosarcoma P1798 cells.
mesh_terms: D000621:Aminoisobutyric Acids / Q000378:metabolism; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000001:Calcimycin / Q000008:administration & dosage / Q000494:pharmacology*; D002118:Calcium / Q000008:administration & dosage / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects; D005260:Female; D066298:In Vitro Techniques; D008214:Lymphocytes / Q000187:drug effects* / Q000378:metabolism; D008228:Lymphoma, Non-Hodgkin / Q000188:drug therapy; D008274:Magnesium / Q000494:pharmacology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D051381:Rats; D012513:Sarcoma, Experimental / Q000188:drug therapy; D013324:Strontium / Q000494:pharmacology; D013601:T-Lymphocytes / Q000187:drug effects; D014529:Uridine / Q000378:metabolism
chemical_list: D000621:Aminoisobutyric Acids; D000900:Anti-Bacterial Agents; D000001:Calcimycin; D008274:Magnesium; D002118:Calcium; D014529:Uridine; D013324:Strontium