TY - JOUR
T1 - The effects of receptor antagonists on the AHH induction activity of 2,3,7,8-TCDD in C57BL/6 and DBA/2 mice
T2 - 1,3,6,8-tetrachlorodibenzofuran
AU - Bannister, R.
AU - Safe, S.
N1 - Funding Information:
This research was financially supported by the National Institute of Health (ESO3843)
Copyright:
Copyright 2014 Elsevier B.V., All rights reserved.
PY - 1987
Y1 - 1987
N2 - Previous studies have demonstrated that 1,3,6,8-tetrachlorodibenzofuran (TCDF) inhibited the induction of aryl hydrocarbon hydroxylase (AHH) and ethoxyresorufin O-deethylase (EROD) in rat hepatoma H-4-II E cells in culture. 1,3,6,8-TCDF did not induce hepatic microsomal AHH or EROD at doses up to 800 umol/kg in DBA/2 mice and 200 umol/kg in C57BL/6 mice. Administration of 1,3,6,8-TCDF to the latter strain of mice resulted in induction of AHH and EROD (< 25% of maximal induction activity). Cotreatment of mDBA/2 mice with 2,3,7,8-TCDD (200 nmol/kg) and with either 50, 200 or 800 umol/kg of 1,3,6,8-TCDF resulted in 13, 39 and 18% inhibition of AHH induction and 17, 34 and 21% inhibition of EROD induction respectively. Cotreatment of the more responsive C57BL/6 mice with 2,3,7,8-TCDD (15 nmol/kg) and 1,3,6,8-TCDF (10, 50, 100, 200 or 500 umol/kg) resulted in significant inhibition (17%) of AHH and EROD induction only at a 200 umol/kg dose level. It was evident that the apparent window of antagonism for 1,3,6,8-TCDF was strain dependent.
AB - Previous studies have demonstrated that 1,3,6,8-tetrachlorodibenzofuran (TCDF) inhibited the induction of aryl hydrocarbon hydroxylase (AHH) and ethoxyresorufin O-deethylase (EROD) in rat hepatoma H-4-II E cells in culture. 1,3,6,8-TCDF did not induce hepatic microsomal AHH or EROD at doses up to 800 umol/kg in DBA/2 mice and 200 umol/kg in C57BL/6 mice. Administration of 1,3,6,8-TCDF to the latter strain of mice resulted in induction of AHH and EROD (< 25% of maximal induction activity). Cotreatment of mDBA/2 mice with 2,3,7,8-TCDD (200 nmol/kg) and with either 50, 200 or 800 umol/kg of 1,3,6,8-TCDF resulted in 13, 39 and 18% inhibition of AHH induction and 17, 34 and 21% inhibition of EROD induction respectively. Cotreatment of the more responsive C57BL/6 mice with 2,3,7,8-TCDD (15 nmol/kg) and 1,3,6,8-TCDF (10, 50, 100, 200 or 500 umol/kg) resulted in significant inhibition (17%) of AHH and EROD induction only at a 200 umol/kg dose level. It was evident that the apparent window of antagonism for 1,3,6,8-TCDF was strain dependent.
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U2 - 10.1016/0045-6535(87)90160-3
DO - 10.1016/0045-6535(87)90160-3
M3 - Article
AN - SCOPUS:0023552351
VL - 16
SP - 1739
EP - 1742
JO - Chemosphere
JF - Chemosphere
SN - 0045-6535
IS - 8-9
ER -