Effect Of Emp On Mice Polydactylia And Related Genes Expression (Gli3, Shh And Fgf4) During The Development Of Mice Limbs

AIM To observe mice polydactylia induced by EMP and related genes expressions (GIB, Shh and Fgf4) during the development of mice limbs. METHODS Mature female mice were mated overnight with male mice, (2:1). The morning on which a vaginal plug was found was designated as fetation-day-0. (Part one) The pregnant mice were randomly divided into control group and EMP radiation group. Mice in the EMP radiation group were exposed to EMP from fetation-day-7 to fetation-day-10. The field intensity was 400kV(.)m(-1) with 400 pulses. On the fetation-day-18, the embryos were taken out by cesarean section. The polydactylia were recorded. Morphological analysis of polydactylia was performed by using Alcian blue-Alizarin red staining method. (Part two) The pregnant mice were randomly divided into negative control group, positive control group and EMP radiation group. Mice in the EMP radiation group were exposed to EMP from fetation-day-7 to fetation-day-10. The field intensity was 400kV(.)m(-1) with 400 pulses. Mice in the positive control group were injected with 300mg center dot kg(-1) of BrdU on the fetation-day-9 and fetation-day-10 days. On fetation-day-11, the embryos were taken out by cesarean section. The expressions of GIB, Shh and Fgf4 were detected by Whole-mount in situ hybridization (WHISH). RESULTS (Part one) Morphological analysis indicated that the polydactylia rate of the EMP radiation group was significantly higher than that of the control group (P < 0.05). And it was also indicated that limb abnormality often occurred to the hindlimbs. (Part two) In embryo limbs (fetation-day-11) of the EMP radiation group and the positive control group, the ectopic expression of Fgf4 was detected in AER; the overexpression and ectopic expression of Shh were detected in the ZPA; the decreased expression of Gli3 was detected in mesenchyme cells. CONCLUSION The occurrence of polydactylia in mice increased after EMP radiation and it may have some relationship with the abnormal expressions of the above -mentioned genes.