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 (CrO(3)) exposure in peripheral blood of mice was studied. Animals were treated with a single intraperitoneal dose of chlorophyllin (CHL) (20mg/kg), CrO(3) (20mg/kg), and CHL (20mg/kg) 4h before (CHL-CrO(3)) or 4h before and 20h after chromium treatments (20mg/kg; CHL-CrO(3)-CHL). Peripheral blood samples were drawn from the caudal vein at 0, 12 and 48h, 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. CrO(3) treatment resulted in a significantly increases 12 and 48h after the injection, reaching a four-fold increase 48h after CrO(3) administration. Whereas treatment with 20mg/kg of CHL prior to chromium, decreased the MN frequency induced by chromium in the 12h samples. When the samples were analyzed 48h after CrO(3) injection, no significant differences between CHL-CrO(3) and CHL-CrO(3)-CHL in comparison with CrO(3) treatment, were observed. These results indicate that increase of MN-PCE by CrO(3) is CHL-blocked in both protocols used (CHL-CrO(3) and CHL-CrO(3)-CHL) at 12h after treatment, but it was unable to modify the frequency of MN-PCE measured 48h after CrO(3) injection. The absence of a protective effect by CHL in the MN-PCE induction by CrO(3) at 48h, show that CHL has action only on one of the times of MN induction and suggests the possible action of CrO(3) by two different mechanisms, and not by CHL time-limited in vivo.