Expressions of glial cell line -derived neurotrophic factor and its tyrosine kinase receptor RET in the terminal rectum of fetal rats with congenital anorectal malformations at different gestational ages
10.3760/cma.j.issn.2095-428X.2016.23.018
- VernacularTitle:胶质细胞源性神经营养因子及其酪氨酸激酶受体RET 在不同胎龄先天性肛门直肠畸形胎鼠直肠末端的表达
- Author:
Yan QU
;
Yuanmei LIU
;
Yuchen MAO
;
Zhu JIN
;
Mingjuan GAO
;
Zebin ZHENG
- Keywords:
Glial cell line -derived neurotrophic factor;
RET;
Signal pathway;
Enteric nervous system;
Con-genital anorectal malformation
- From:
Chinese Journal of Applied Clinical Pediatrics
2016;31(23):1829-1833
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the expressions and distributions of glial cell line -derived neurotrophic factor (GDNF)and itstyrosine kinase receptor RET in the terminal rectums of fetal rats with congenital anorectal malfor-mations (ARM)at different gestationalage,and to explore their effects on the enteric nervous system in the terminal rectum of ARMfetal rats.Methods Thirty -five SD pregnancy rats were divided into a saline group (n =1 0)and an ethylenethiourea experiment group (n =25)by simple randomized study.The fetal rats were removed from the pregnant rats at the gestational 1 6 d,1 8 d and 20 d.The fetal rats were divided into the saline control group,the ethylenethiourea control group (fetal rats without ARM)and the ethylenethiourea malformation group (ARM fetal rats)by the naked eye and dissecting microscope.HE staining was used to observe the morphology and the intestinal ganglion cells in the terminal rectum were counted.The immunohistochemical staining and Western blot methods were used to observe the distributions of GDNF and RET in the rectum at the gestational 1 6 d,1 8 d and 20 d.The quantitative real -time poly-merase chain reaction (qRT -PCR)was used to detect the expression of GDNF mRNA in the fetal rats in the terminal rectum at the gestational 1 6 d,1 8 d and 20 d.Results HE staining:the development of anorectal terminal in 3 groups of fetal rats was unclear at the gestational 1 6 d.A small amount of scattered nerve plexuses were observed in the muscu-lar layer.The nuclei were small and sparse.The axons and cytoplasms were less.The serosal layer,muscular layer,sub-mucosa,mucosal layer and glands in the terminal rectum were gradually clear in the saline control group and the ethyle-nethiourea control group at the gestational 1 8 d and 20 d.The intermuscular submucosal nerve plexuses increased gra-dually (1 1 .400 ±3.1 34 and 1 1 .200 ±3.425 at the gestational 1 8 d;66.1 00 ±4.954 and 67.600 ±5.481 at the gesta-tional 20 d).While,the layer was unclear in the ethylenethiourea malformation group and the nerve plexus was less (7.800 ±1 .989 at the gestational 1 8 d,and 25.200 ±3.048 at the gestational 20 d),and the difference was statistical-ly significant compared with 2 control groups (F =7.591 ,271 .833,all P <0.05).Immunohistochemistry satning:the expressions of GDNF and RET in all layers of the intestinal wall in the 3 groups of fetal rats were unclear at the gesta-tional 1 6 d and only a few positive cells were observed.The GDNF and RET were expressed in the mucosal layer and submucosa of the terminal rectum as well as intermuscular nerve plexus in the saline control group and the ethylene-thioured control group at the gestational 1 8 d and 20 d.With the continuous development of the embryo,their expression intensities were gradually increased.The expressions of GDNF and RET positive cells were decreased gradually in the ethylenethiourea malformation group.The difference was significant statistically compared with 2 control groups (all P <0.05).qRT -PCR:the expressions of GDNF mRNA showed no statistical difference among 3 groups at the gestational 1 6 d (P >0.05);the expressions of GDNF and RET protein were 1 03.624 ±27.533 and 1 05.1 84 ±1 9.634 at the ges-tational 1 8 d;1 51 .496 ±33.622 and 1 50.738 ±21 .423 at the gestational 20 d in 2 control groups.Compared with the ethylenethiourea malformation group (79.1 69 ±1 1 .697 at the gestational 1 8 d;94.873 ±1 1 .309 at the gestational 20 d),and the difference were statistically significant (all P <0.05).Conclusions The expressions of GDNF and its tyrosine kinase receptor RET had a certain temporal correlation in the terminal rectum of normal fetal rats at different gestational ages and ARM.Moreover,the abnormal expressions of GDNF and its tyrosine kinase receptor RET in the dis-tal rectum of ARMfetal rats can affect the development of enteric nervous system.
