title: Immediate and short-, mid- and long-term effects of in vivo ionizing radiation exposure in BALB/c mice: II. activation of phorbol myristate acetate and/or calcium ionophore on lymphocyte proliferation.
abstract: OBJECTIVE
  To study the effects of whole-body irradiation (WBI) on lymphocyte proliferation at different times (0, 7, 15, 30, 90 and 180 days) in an animal sensitive to radiation, BALB/c-mice.
  
  
  METHODS
  Mice were irradiated (4 Gy) and euthanized at different times, and lymphocytes underwent different treatments: quiescent cells were cultured with calcium ionophore (5 min or 48 h) with/without phorbol myristate acetate (PMA). Lymphocytes were cultured with mitogens and underwent the same treatment. Cell proliferation was measured by a tritiated thymidine assay.
  
  
  RESULTS
  The results obtained varied at different time points: at 15 days post-irradiation, quiescent cells and PMA-treated cells showed a significantly decreased proliferation, but increased at 90 days; moreover, when cells were treated with ionophore, a significant stimulation was noted at all times. When cells were exposed to mitogens, they behaved according to its nature: thus, concanavalin A (ConA) and phytohaemaglutinin A (PHA) behaved differently with PMA, while lipopolysaccharide (LPS) had an inhibitory effect at 30 days post-irradiation, and pokeweed (PWM) stimulated proliferation at both 90 and 180 days. Accordingly, there were very few variations in the test results when mitogen concanavalin A (ConA) and calcium ionophore with/without PMA were used.
  
  
  CONCLUSIONS
  Our model is based on BALB/c mice. Cells induced to proliferate by the PKC enzyme and calcium ionophore are more resistant to irradiation than the same cells treated with specific T- and B-cells mitogen.
authors.affiliation: Experimental Immunology Unit, Research Centre, University Hospital La Fe, Valencia, Spain.
authors.forename: Joaquín
authors.initials: J
authors.lastname: Hernández-Godoy
authors.forename: Dolores
authors.initials: D
authors.lastname: Planelles
authors.forename: Baltasar
authors.initials: B
authors.lastname: Balsalobre
mesh_terms: D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D061207:Calcium Ionophores / Q000494:pharmacology; D049109:Cell Proliferation / Q000187:drug effects / Q000528:radiation effects*; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D002478:Cells, Cultured; D003208:Concanavalin A / Q000494:pharmacology; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005720:Gamma Rays; D008213:Lymphocyte Activation / Q000187:drug effects / Q000528:radiation effects; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000528:radiation effects*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008934:Mitogens / Q000494:pharmacology; D010835:Phytohemagglutinins / Q000494:pharmacology; D013154:Spleen / Q000166:cytology / Q000187:drug effects / Q000528:radiation effects; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013997:Time Factors; D014916:Whole-Body Irradiation / Q000379:methods*
chemical_list: D061207:Calcium Ionophores; D008934:Mitogens; D010835:Phytohemagglutinins; D003208:Concanavalin A; D000001:Calcimycin; D013755:Tetradecanoylphorbol Acetate