Color Doppler Ultrasound Irradiation, Expression Of Caspase8 And Second Trimester Fetal Rat Central Nervous System Neuronal Apoptosis And Of Caspase3 Impact

Objective: This experiment was to study the effect on apoptosis of central neurons and the mechanism of central neurons apoptosis caused by diagnostic Color Doppler Ultrasound so as to provide new evidence of safety of clinical ultrasound application.Methods: 20 rats of Kunming species which had been pregnant for 12---14 days were chosen as mid-pregnancy models. Pregnant rats were randomly divided into 4 groups of the same number according to different exposure time: GroupI 0min (control group); Group II 10min; Group III 20min; GroupIV 30min.(Esaote DU8 H 3.0MHz CFM 2.0MHz MI=0.7 TIS=0.6 TIB=1.7). Fetal rats were chosen 24 hours after being exposed. 1. Them was made into conventional pathological slice. Its central neurons apoptosis were detected by TUNEL. Through observing by microscope, apoptosis index AI was got. 2.Then detect the fetal rat for expression of Caspase3mRNA and Caspase8mRNA in central neurons by PT-PCR. The results were analyzed with SPSS11.5.Results: Compare apoptosis indexs of GroupI and GroupII and analyze the result. There is no statistical meaning (P>0.05). While there are statistical meanings between the differences of apoptosis index of GroupI and GroupIII and that of GroupI and GroupIV(P<0.05). Compare the expression level of Caspase3mRNA and Caspase8mRNA of GroupI and GroupII and analyze the result. There is no statistical meaning (P>0.05). While there are statistical meanings between the difference of the expression level of Caspase3mRNA and Caspase8mRNA of GroupI and GroupIII and that of GroupI and GroupIV(P<0.05).Conclusions: From the view of instant and short-term biological effect, irradiating mid-pregnancy rat for over 20 min by transabdominal Color Doppler Ultrasound will cause increase of apoptosis of fetal rat's central neurons as well as the expression of Caspase3mRNA and Caspase8mRNA. The higher expression of Caspase3mRNA and Caspase8mRNA further suggests that cytomembrane pathway may be one of the mechanisms of central neurons apoptosis. Continuous irradiation by diagnostic dosages of Color Doppler Ultrasound will induce potential damages to central neurons. For this reason, it must be prevented to irradiate the same area of embryo continuously.