[The disruptive effect of N'N-methylene-bis on the function of FRTL-5 cells].
OBJECTIVE
To study the impact of N' N-methylene-bis on thyroglobulin produced by FRTL-5 cells, and to explore the potential of using FRTL-5 cells to screen environmental thyroid hormone disruptors in vitro.


METHODS
The FRTL-5 cells were treated with 0.1, 1.0 and 10.0 microg/mL N'N-methylene-bis for 48 hours, respectively. The concentrations of thyroglobulin in the medium of the treated cells were detected by radioimmunoassay. The expression of thyroid peroxidases in the FRTL-5 cells was assessed by enzyme cytochemistry technique. The ultrastructure of the cells was also observed.


RESULTS
The FRTL-5 cells treated with 0.1 and 1.0 microg/mL of N' N-methylene-bis produced less thyroglobulin than the controls (P < 0.05). No thyroglobulin was detected with the cells treated with 10.0 microg/mL of N' N-methylene-bis. No difference in the expression of thyroid peroxidases was found between the treated cells and the controls. The treated cells had expanded rough endoplasmic reticulum.


CONCLUSIONS
N' N-methylene-bis disrupts the bio-function of thyroid by damaging the rough endoplasmic reticulum of thyroid follicular cells. FRTL-5 cells can be used for screening thyroid hormone disruptors in vitro.
Qiu
Yong-Jie
YJ
Department of Environmental Health, West China School of Public Health, Sichuan University, Chengdu, China.
Zhang
Hao
H
Sun
Ding
D
Qiu
Yun-Liang
YL
Wang
Jin-Tao
JT
D000818:Animals; D002460:Cell Line; D052244:Endocrine Disruptors / Q000633:toxicity*; D018870:Endoplasmic Reticulum, Rough / Q000187:drug effects; D007453:Iodide Peroxidase / Q000032:analysis; D010575:Pesticides / Q000633:toxicity*; D051381:Rats; D013830:Thiadiazoles / Q000633:toxicity*; D013954:Thyroglobulin / Q000032:analysis*; D013961:Thyroid Gland / Q000166:cytology / Q000187:drug effects*
D052244:Endocrine Disruptors; D010575:Pesticides; D013830:Thiadiazoles; C044397:N,N'-methylene-bis(2-amino-5-sulfhydryl-1,3,4-thiadiazole); D013954:Thyroglobulin; D007453:Iodide Peroxidase