Objective   To investigate DNA strand breaks and micronuclei induced by sodium pentachlorophen(NaPCP)in different phases and different dosages in vivo.

  Methods   Mice were treated through gavage with Na-PCP at a dose of 0, 25, 50 and 100 mg/kg once time and 0, 6.25, 12.5 and 25 mg/kg for one month.Mice were sacrificed at the end of 3, 24 and 48 hours after once treatment or after one month treatment.DNA strand breaks were detected in the splenocyte, thymocyte, and macrophage through SCGE(Single Cell Gel Electrophoresis).At the same time after once treatment micronuclei in polychromatic erythrocyte in bone marrow were also detected.

  Results   It was showed that 3-hours different dosages treatment of 50 and 100 mg/kg Na-PCP could induce DNA damage not only in the frequency of comet cell but also in the migration of DNA breaks in cells from spleen.Only 100 mg/kg Na-PCP could induce DNA damage in macrophage.In contrast there was no change in cells from thymus in different dosage treatment and different treating period.Doring the research of different time-course study it was presented that 24-hour and 48-hour treatment was with no significant DNA strand breaks in each kind of cells.Na-PCP did not induce micronuclei in polychromatic erythrocyte under the condition of this assay.

  Conclusion   50 and 100 mg/kg Na-PCP could induce DNA strand breaks in cells from spleen.100 mg/kg Na-PCP could induce DNA strand breaks in macrophage.Thymus was insensitive to this kind of damage induced by Na-PCP and Na-PCP did not induce the increase of micronuclei in polychromatic erythrocyte under the condition of this assay.