TY - JOUR
T1 - Effects of 3,4-dichloroaniline on expression of ahr2 and cyp1a1 in zebrafish adults and embryos
AU - Ito, Yoshie
AU - Matsuda, Youhei
AU - Suzuki, Tohru
N1 - Funding Information:
This research was supported by a grant from the Ministry of Education, Culture, Sports, Science, and Technology of Japan to TS (no. 19650872 ).
PY - 2010/8
Y1 - 2010/8
N2 - Arylhydrocarbon receptor (Ahr) and cytochrome P4501a1 (Cyp1a1) are members of the Ahr/Cyp1a1 pathway that oxygenates various toxic chemicals including aryl hydrocarbons. To elucidate Ahr/Cyp1a1 pathway responses in teleost fish tissues, we examined the effects of 3,4-dichloroaniline (3,4-DCA), a reference toxic compound known to activate the Ahr/Cyp1a1 pathway, on the expression of arh and cyp1a1 in zebrafish tissues and embryos by means of in situ hybridization (ISH). Our ISH analysis showed that cyp1a1 expression was markedly activated by 3,4-DCA in the gill and intestinal epithelia, skin epidermis, and liver parenchymal cells of adult zebrafish. Before differentiation of the gill, intestine, and liver, skin was the site of cyp1a1 activation in embryos. Unlike the cyp1a1 response, 3,4-DCA-mediated ahr activation was not marked in either adults or embryos, indicating a possibility that stable ahr transcripts persist in the cytoplasm of these cells to induce cyp1a1. Young oocytes (previtellogenic to early vitellogic stage) express ahr; however activation of cyp1a1 by 3,4-DCA was negligible in these oocytes, suggesting that ahr expression in oocytes is not directly linked to cyp1a1 activation. Based on our finding that skin epidermis up-regulates cyp1a1 in response to 3,4-DCA, we demonstrated that fin explants, which can be harvested without sacrificing fish, can be used as a standard for assaying cyp1a1 activation in addition to embryos that are now used.
AB - Arylhydrocarbon receptor (Ahr) and cytochrome P4501a1 (Cyp1a1) are members of the Ahr/Cyp1a1 pathway that oxygenates various toxic chemicals including aryl hydrocarbons. To elucidate Ahr/Cyp1a1 pathway responses in teleost fish tissues, we examined the effects of 3,4-dichloroaniline (3,4-DCA), a reference toxic compound known to activate the Ahr/Cyp1a1 pathway, on the expression of arh and cyp1a1 in zebrafish tissues and embryos by means of in situ hybridization (ISH). Our ISH analysis showed that cyp1a1 expression was markedly activated by 3,4-DCA in the gill and intestinal epithelia, skin epidermis, and liver parenchymal cells of adult zebrafish. Before differentiation of the gill, intestine, and liver, skin was the site of cyp1a1 activation in embryos. Unlike the cyp1a1 response, 3,4-DCA-mediated ahr activation was not marked in either adults or embryos, indicating a possibility that stable ahr transcripts persist in the cytoplasm of these cells to induce cyp1a1. Young oocytes (previtellogenic to early vitellogic stage) express ahr; however activation of cyp1a1 by 3,4-DCA was negligible in these oocytes, suggesting that ahr expression in oocytes is not directly linked to cyp1a1 activation. Based on our finding that skin epidermis up-regulates cyp1a1 in response to 3,4-DCA, we demonstrated that fin explants, which can be harvested without sacrificing fish, can be used as a standard for assaying cyp1a1 activation in addition to embryos that are now used.
KW - 3,4-dichroloaniline
KW - Arylhydrocarbon receptor
KW - Cytochrome p4501a1
KW - Danio rerio
KW - Detoxication
KW - In situ hybridization
KW - Zebrafish
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U2 - 10.1016/j.cbpc.2010.04.002
DO - 10.1016/j.cbpc.2010.04.002
M3 - Article
C2 - 20398795
AN - SCOPUS:77952745332
VL - 152
SP - 189
EP - 194
JO - Comparative Biochemistry and Physiology - C Toxicology and Pharmacology
JF - Comparative Biochemistry and Physiology - C Toxicology and Pharmacology
SN - 1532-0456
IS - 2
ER -