Effects Of Atrazine On The Developmental Potential Of ICR Mouse Oocytes

Atrazine (2-chloro-4-ethlamino-6-isopropyl-amino-s-triazine, ATR) is one of herbicide being used in the worldwide due to low toxicity and prices. Atrazine has stable chemical properties. Atrazine has a wide range of pollution and has been detected in many countries’soil water and atmosphere. Atrazine can accumulate in the biological body. It has been reported that atrazine and its metabolites has affected on mammalian endocrine system, nervous system, immune and reproductive systems in recent years. Atrazine has the effect of environmental estrogens. In the study, female ICR mice’s oocytes were cultured in M2medium with1μg/ml,0.1μg/ml,10μg/ml atrazine separately in vitro. To observe the rate of GVBD, PBI and parthenogenetic activation, the effect of atrzine on chromosome’s arrangement, spindle area and spindle’s morphology were observed by confocal and the level of apoptosis in cumulus cells was detected by TUNEL. The aim of this study was to investigate the effect of atrazine on ICR mice’s oocyte maturation and development ability in vitro. Experimental Results(1) The effect of atrazine on oocytes’GVBD rate (COCs).The rate of germinal vesicle breakdown was counted. The results showed that there was no significant difference between the control group and the atrzaine treated groups (P>0.05).(2)The effect of atrazine on oocytes’PBI rate (COCs).The rate of the first polar body extrusion was counted. The results showed that there was no significant difference between the control group and0.1μg/ml or1μg/ml atrzaine treated groups (P>0.05). The rate of the first polar body extrusion of10μg/ml experiment group was significantly lower compared with control group (P>0.05).(3)The effect of atrazine on nude oocytes’ rate of GVBD and PBI.The rates of nude oocytes’ GVBD and PBI were counted. The results showed that there was no significant difference between the control group and the atrazine treated groups.(4) The effect of atrazine on the rate of oocytes’ partheno genetic activation (COCs).The rate of oocytes’ partheno genetic activation was counted. The results showed that there was no significant difference between the control group and0.1μg/ml or1μg/ml atrzaine treated groups (P>0.05). The rate of oocytes’parthenogenetic activation of10μg/ml experiment group was significantly lower compared with control group (P>0.05).(5) The effect of atrazine on ICR mice oocytes’chromosome arrangement in the stage of MⅡ.The rate of oocytes’chromosome arrangement was counted. The results showed that there was no significant difference in1μg/ml and1μg/ml atrzaine treated groups compare to the control group (P>0.05). The rate of oocytes’ chromosome arrangement of10μg/ml experiment group was significantly lower compared with control group (P<0.05).(6)The effect of atrazine on ICR mice oocytes’spindle area.The results showed that there was no significant difference in0.1μg/ml and1μg/ml atrzaine treated groups compare to the control group (P>0.05). The spindle areas in10μg/ml experiment group was significantly larger than the control group (P<0.05). Furthermore, spindle of shape in oocytes treated by0.1μg/ml,1μg/ml,10μg/ml became dispersed.(7) The effect of atrazine on ICR mice cumulus cells’ apoptosis.The rate of cumulus cells’ apoptosis was counted. The results showed that there was no significant difference in0.1μg/ml and1μg/ml atrzaine treated groups compare to control group (P>0.05). The rate of cumulus cells’apoptosis of10μg/ml experiment group was significantly higher compared with control group (P>0.05).