Effect of chlorophyllin on chromium trioxide-induced micronuclei in polychromatic erythrocytes in mouse peripheral blood

The effect of chlorophyllin on micronucleated polychromatic erythrocytes (MN-PCE) induction by chromium trioxide (CrO3) exposure in peripheral blood of mice was studied. Animals were treated with a single intraperitoneal dose of chlorophyllin (CHL) (20 mg/kg), CrO3 (20 mg/kg), and CBL (20 mg/kg) 4 h before (CHL-CrO3) or 4 h before and 20 h after chromium treatments (20 mg/kg; CBL-CrO3-CHL). Peripheral blood samples were drawn from the caudal vein at 0, 12 and 48 h, and analyzed by the acridine orange (AO) technique. The results obtained in present study shown that CHL injection did not modify the number of MN-PCE. CrO3 treatment resulted in a significantly increases 12 and 48 h after the injection, reaching a four-fold increase 48 h after CrO3 administration. Whereas treatment with 20 mg/kg of CBL prior to chromium, decreased the MN frequency induced by chromium in the 12 h samples. When the samples were analyzed 48 h after CrO3 injection, no significant differences between CBL-CrO3 and CHL-CrO3-CHL in comparison with CrO3 treatment, were observed. These results indicate that increase of MN-PCE by CrO3 is CHL-blocked in both protocols used (CBL-CrO3 and CBL-CrO3-CHL) at 12 h after treatment, but it was unable to modify the frequency of MN-PCE measured 48 h after CrO3 injection. The absence of a protective effect by CBL in the MN-PCE induction by CrO3 at 48 h, show that CBL has action only on one of the times of MN induction and suggests the possible action Of CrO3 by two different mechanisms, and not by CBL time-limited in vivo. (C) 2001 Elsevier Science B.V. All rights reserved.