Influence of β-Naphthoflavone and Methoxychlor Pretreatment on the Biotransformation and Estrogenic Activity of Methoxychlor in Channel Catfish (Ictalurus punctatus)
The organochlorine pesticide methoxychlor [1,1,1-trichloro-2,2-bis(4-methoxyphenyl) ethane] (MXC) has been classified as a proestrogen in mammals and fish, requiring demethylation prior to eliciting estrogenic activity or binding to the estrogen receptor. While microsomal demethylation occurs readil...
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| Veröffentlicht in: | Toxicology and applied pharmacology 1997-08, Vol.145 (2), p.349-356 |
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| creator | Schlenk, Daniel Stresser, David M. McCants, John C. Nimrod, Alison C. Benson, William H. |
| description | The organochlorine pesticide methoxychlor [1,1,1-trichloro-2,2-bis(4-methoxyphenyl) ethane] (MXC) has been classified as a proestrogen in mammals and fish, requiring demethylation prior to eliciting estrogenic activity or binding to the estrogen receptor. While microsomal demethylation occurs readily in the liver of fish, little is known about the enzyme(s) responsible or the effect of cytochrome P450 (CYP) inducers, other than those of CYP1A and CYP2K, on biotransformation. Consequently, male channel catfish were pretreated with MXC or β-naphthoflavone (BNF), alone and in combination, to determine their effects on CYP protein expression, MXC biotransformation by hepatic microsomes, microsomal protein binding, and MXC estrogenic activity as determined by serum vitellogenin and 17β-estradiol. Liver microsomes of both treated and untreated mature male catfish catalyzed formation of monodemethylated MXC, bisdemethylated MXC, as well as ring-hydroxylated metabolites. Pretreatment with BNF did not affect MXC metabolite profiles, overall rates of MXC biotransformation, or microsomal proteins recognized by anti-trout CYP2K1, but had the expected effect of inducing CYP1A and associated ethoxyresorufinO-deethylase activity. By contrast, pretreatment with MXC, alone or in combination with BNF, significantly reduced rates of MXC biotransformation and binding to liver microsomal protein. MXC/BNF cotreatment followed by MXC significantly induced serum vitellogenin, whereas MXC treatment alone led to a nonsignificant increase in vitellogenin and a significant increase in serum 17β-estradiol. Thus, estrogenic activity elicited by cotreatment with MXC and BNF can occur despite diminished capacity of liver microsomes to catalyze formation of estrogenic demethylated metabolites or metabolites that bind microsomal protein. Possible mechanisms of MXC-induced attenuation of CYP-dependent metabolism are discussed. |
| doi_str_mv | 10.1006/taap.1997.8194 |
| format | Article |
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While microsomal demethylation occurs readily in the liver of fish, little is known about the enzyme(s) responsible or the effect of cytochrome P450 (CYP) inducers, other than those of CYP1A and CYP2K, on biotransformation. Consequently, male channel catfish were pretreated with MXC or β-naphthoflavone (BNF), alone and in combination, to determine their effects on CYP protein expression, MXC biotransformation by hepatic microsomes, microsomal protein binding, and MXC estrogenic activity as determined by serum vitellogenin and 17β-estradiol. Liver microsomes of both treated and untreated mature male catfish catalyzed formation of monodemethylated MXC, bisdemethylated MXC, as well as ring-hydroxylated metabolites. Pretreatment with BNF did not affect MXC metabolite profiles, overall rates of MXC biotransformation, or microsomal proteins recognized by anti-trout CYP2K1, but had the expected effect of inducing CYP1A and associated ethoxyresorufinO-deethylase activity. By contrast, pretreatment with MXC, alone or in combination with BNF, significantly reduced rates of MXC biotransformation and binding to liver microsomal protein. MXC/BNF cotreatment followed by MXC significantly induced serum vitellogenin, whereas MXC treatment alone led to a nonsignificant increase in vitellogenin and a significant increase in serum 17β-estradiol. Thus, estrogenic activity elicited by cotreatment with MXC and BNF can occur despite diminished capacity of liver microsomes to catalyze formation of estrogenic demethylated metabolites or metabolites that bind microsomal protein. Possible mechanisms of MXC-induced attenuation of CYP-dependent metabolism are discussed.</description><identifier>ISSN: 0041-008X</identifier><identifier>EISSN: 1096-0333</identifier><identifier>DOI: 10.1006/taap.1997.8194</identifier><identifier>PMID: 9266808</identifier><identifier>CODEN: TXAPA9</identifier><language>eng</language><publisher>San Diego, CA: Elsevier Inc</publisher><subject>ACTIVADOR ENZIMATICO ; ACTIVATEUR D'ENZYME ; ACTIVIDAD ENZIMATICA ; ACTIVITE ENZYMATIQUE ; Animals ; beta-Naphthoflavone - administration & dosage ; beta-Naphthoflavone - pharmacology ; Biological and medical sciences ; Biotransformation - drug effects ; BLOOD SERUM ; CITOCROMO P450 ; Cytochrome P-450 Enzyme System - biosynthesis ; CYTOCHROME P450 ; CYTOPLASMIC ORGANELLES ; ENZYME ACTIVATORS ; Enzyme Induction - drug effects ; ENZYMIC ACTIVITY ; Estradiol - blood ; ESTROGENIC PROPERTIES ; ESTROGENOS ; Estrogens - blood ; FLAVONOIDE ; FLAVONOIDES ; FLAVONOIDS ; FOIE ; Freshwater ; HIGADO ; Ictaluridae ; ICTALURUS ; Ictalurus punctatus ; Injections, Intraperitoneal ; LIVER ; Male ; Medical sciences ; METABOLISM ; METABOLISME ; METABOLISMO ; METABOLITE ; METABOLITES ; METABOLITOS ; METHOXYCHLOR ; Methoxychlor - administration & dosage ; Methoxychlor - pharmacokinetics ; Methoxychlor - pharmacology ; METHOXYCHLORE ; METOXICLORO ; MICROSOMES ; Microsomes, Liver - drug effects ; Microsomes, Liver - enzymology ; OESTROGENE ; OESTROGENS ; ORGANITE CELLULAIRE ; ORGANULOS CITOPLASMICOS ; OXIDOREDUCTASES ; OXIDORREDUCTASAS ; OXYDOREDUCTASE ; Pesticides, fertilizers and other agrochemicals toxicology ; SERUM SANGUIN ; SUERO SANGUINEO ; Toxicology ; UNSPECIFIC MONOOXYGENASE ; VITELLOGENINE ; VITELLOGENINS ; Vitellogenins - blood ; VITELOGENINA</subject><ispartof>Toxicology and applied pharmacology, 1997-08, Vol.145 (2), p.349-356</ispartof><rights>1997 Academic Press</rights><rights>1997 INIST-CNRS</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c421t-1b87cadd316a73c74a8fcab4b986b5996d1ad05c8e2a191e45fe495bb88e70893</citedby><cites>FETCH-LOGICAL-c421t-1b87cadd316a73c74a8fcab4b986b5996d1ad05c8e2a191e45fe495bb88e70893</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktohtml>$$Uhttps://dx.doi.org/10.1006/taap.1997.8194$$EHTML$$P50$$Gelsevier$$H</linktohtml><link.rule.ids>315,782,786,3554,27933,27934,46004</link.rule.ids><backlink>$$Uhttp://pascal-francis.inist.fr/vibad/index.php?action=getRecordDetail&idt=2786957$$DView record in Pascal Francis$$Hfree_for_read</backlink><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/9266808$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Schlenk, Daniel</creatorcontrib><creatorcontrib>Stresser, David M.</creatorcontrib><creatorcontrib>McCants, John C.</creatorcontrib><creatorcontrib>Nimrod, Alison C.</creatorcontrib><creatorcontrib>Benson, William H.</creatorcontrib><title>Influence of β-Naphthoflavone and Methoxychlor Pretreatment on the Biotransformation and Estrogenic Activity of Methoxychlor in Channel Catfish (Ictalurus punctatus)</title><title>Toxicology and applied pharmacology</title><addtitle>Toxicol Appl Pharmacol</addtitle><description>The organochlorine pesticide methoxychlor [1,1,1-trichloro-2,2-bis(4-methoxyphenyl) ethane] (MXC) has been classified as a proestrogen in mammals and fish, requiring demethylation prior to eliciting estrogenic activity or binding to the estrogen receptor. While microsomal demethylation occurs readily in the liver of fish, little is known about the enzyme(s) responsible or the effect of cytochrome P450 (CYP) inducers, other than those of CYP1A and CYP2K, on biotransformation. Consequently, male channel catfish were pretreated with MXC or β-naphthoflavone (BNF), alone and in combination, to determine their effects on CYP protein expression, MXC biotransformation by hepatic microsomes, microsomal protein binding, and MXC estrogenic activity as determined by serum vitellogenin and 17β-estradiol. Liver microsomes of both treated and untreated mature male catfish catalyzed formation of monodemethylated MXC, bisdemethylated MXC, as well as ring-hydroxylated metabolites. Pretreatment with BNF did not affect MXC metabolite profiles, overall rates of MXC biotransformation, or microsomal proteins recognized by anti-trout CYP2K1, but had the expected effect of inducing CYP1A and associated ethoxyresorufinO-deethylase activity. By contrast, pretreatment with MXC, alone or in combination with BNF, significantly reduced rates of MXC biotransformation and binding to liver microsomal protein. MXC/BNF cotreatment followed by MXC significantly induced serum vitellogenin, whereas MXC treatment alone led to a nonsignificant increase in vitellogenin and a significant increase in serum 17β-estradiol. Thus, estrogenic activity elicited by cotreatment with MXC and BNF can occur despite diminished capacity of liver microsomes to catalyze formation of estrogenic demethylated metabolites or metabolites that bind microsomal protein. Possible mechanisms of MXC-induced attenuation of CYP-dependent metabolism are discussed.</description><subject>ACTIVADOR ENZIMATICO</subject><subject>ACTIVATEUR D'ENZYME</subject><subject>ACTIVIDAD ENZIMATICA</subject><subject>ACTIVITE ENZYMATIQUE</subject><subject>Animals</subject><subject>beta-Naphthoflavone - administration & dosage</subject><subject>beta-Naphthoflavone - pharmacology</subject><subject>Biological and medical sciences</subject><subject>Biotransformation - drug effects</subject><subject>BLOOD SERUM</subject><subject>CITOCROMO P450</subject><subject>Cytochrome P-450 Enzyme System - biosynthesis</subject><subject>CYTOCHROME P450</subject><subject>CYTOPLASMIC ORGANELLES</subject><subject>ENZYME ACTIVATORS</subject><subject>Enzyme Induction - drug effects</subject><subject>ENZYMIC ACTIVITY</subject><subject>Estradiol - blood</subject><subject>ESTROGENIC PROPERTIES</subject><subject>ESTROGENOS</subject><subject>Estrogens - blood</subject><subject>FLAVONOIDE</subject><subject>FLAVONOIDES</subject><subject>FLAVONOIDS</subject><subject>FOIE</subject><subject>Freshwater</subject><subject>HIGADO</subject><subject>Ictaluridae</subject><subject>ICTALURUS</subject><subject>Ictalurus punctatus</subject><subject>Injections, Intraperitoneal</subject><subject>LIVER</subject><subject>Male</subject><subject>Medical sciences</subject><subject>METABOLISM</subject><subject>METABOLISME</subject><subject>METABOLISMO</subject><subject>METABOLITE</subject><subject>METABOLITES</subject><subject>METABOLITOS</subject><subject>METHOXYCHLOR</subject><subject>Methoxychlor - administration & dosage</subject><subject>Methoxychlor - pharmacokinetics</subject><subject>Methoxychlor - pharmacology</subject><subject>METHOXYCHLORE</subject><subject>METOXICLORO</subject><subject>MICROSOMES</subject><subject>Microsomes, Liver - drug effects</subject><subject>Microsomes, Liver - enzymology</subject><subject>OESTROGENE</subject><subject>OESTROGENS</subject><subject>ORGANITE CELLULAIRE</subject><subject>ORGANULOS CITOPLASMICOS</subject><subject>OXIDOREDUCTASES</subject><subject>OXIDORREDUCTASAS</subject><subject>OXYDOREDUCTASE</subject><subject>Pesticides, fertilizers and other agrochemicals toxicology</subject><subject>SERUM SANGUIN</subject><subject>SUERO SANGUINEO</subject><subject>Toxicology</subject><subject>UNSPECIFIC MONOOXYGENASE</subject><subject>VITELLOGENINE</subject><subject>VITELLOGENINS</subject><subject>Vitellogenins - blood</subject><subject>VITELOGENINA</subject><issn>0041-008X</issn><issn>1096-0333</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>1997</creationdate><recordtype>article</recordtype><sourceid>EIF</sourceid><recordid>eNqFks2KFDEQxxtR1nH16k3IQUQPPSb9kU6O67DqwPoBuuAtVKcr25GepE3Sg_NCPoAP4jPZzQwrHsRTQtWv_lWpf7LsMaNrRil_mQDGNZOyWQsmqzvZilHJc1qW5d1sRWnFckrFl_vZgxi_UkplVbGz7EwWnAsqVtmPrTPDhE4j8Yb8-pm_h7FPvTcD7L1DAq4j73AOfD_ofvCBfAyYAkLaoUvEO5J6JK-sTwFcND7sINk5upRdxhT8DTqryYVOdm_TYenxl5p1ZNODcziQDSRjY0-eb3WCYQpTJOPk5nua4ouH2T0DQ8RHp_M8u359-XnzNr_68Ga7ubjKdVWwlLNWNBq6rmQcmlI3FQijoa1aKXhbS8k7Bh2ttcACmGRY1QYrWbetENhQIcvz7NlRdwz-24QxqZ2NGocBHPopqkYWRckL9l-QcUarWhYzuD6COvgYAxo1BruDcFCMqsVBtTioFgfV4uBc8OSkPLU77G7xk2Vz_ukpD1HDYObFaxtvsaIRXNbNHxkDXsFNmJHrT0sX2rCSLw8QxzzO69xbDCpqu_yDzgbUSXXe_mvC38JrxRU</recordid><startdate>19970801</startdate><enddate>19970801</enddate><creator>Schlenk, Daniel</creator><creator>Stresser, David M.</creator><creator>McCants, John C.</creator><creator>Nimrod, Alison C.</creator><creator>Benson, William H.</creator><general>Elsevier Inc</general><general>Elsevier</general><scope>FBQ</scope><scope>IQODW</scope><scope>CGR</scope><scope>CUY</scope><scope>CVF</scope><scope>ECM</scope><scope>EIF</scope><scope>NPM</scope><scope>AAYXX</scope><scope>CITATION</scope><scope>7U7</scope><scope>7UA</scope><scope>C1K</scope><scope>F1W</scope><scope>H97</scope><scope>L.G</scope><scope>7X8</scope></search><sort><creationdate>19970801</creationdate><title>Influence of β-Naphthoflavone and Methoxychlor Pretreatment on the Biotransformation and Estrogenic Activity of Methoxychlor in Channel Catfish (Ictalurus punctatus)</title><author>Schlenk, Daniel ; Stresser, David M. ; McCants, John C. ; Nimrod, Alison C. ; Benson, William H.</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c421t-1b87cadd316a73c74a8fcab4b986b5996d1ad05c8e2a191e45fe495bb88e70893</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>1997</creationdate><topic>ACTIVADOR ENZIMATICO</topic><topic>ACTIVATEUR D'ENZYME</topic><topic>ACTIVIDAD ENZIMATICA</topic><topic>ACTIVITE ENZYMATIQUE</topic><topic>Animals</topic><topic>beta-Naphthoflavone - administration & dosage</topic><topic>beta-Naphthoflavone - pharmacology</topic><topic>Biological and medical sciences</topic><topic>Biotransformation - drug effects</topic><topic>BLOOD SERUM</topic><topic>CITOCROMO P450</topic><topic>Cytochrome P-450 Enzyme System - biosynthesis</topic><topic>CYTOCHROME P450</topic><topic>CYTOPLASMIC ORGANELLES</topic><topic>ENZYME ACTIVATORS</topic><topic>Enzyme Induction - drug effects</topic><topic>ENZYMIC ACTIVITY</topic><topic>Estradiol - blood</topic><topic>ESTROGENIC PROPERTIES</topic><topic>ESTROGENOS</topic><topic>Estrogens - blood</topic><topic>FLAVONOIDE</topic><topic>FLAVONOIDES</topic><topic>FLAVONOIDS</topic><topic>FOIE</topic><topic>Freshwater</topic><topic>HIGADO</topic><topic>Ictaluridae</topic><topic>ICTALURUS</topic><topic>Ictalurus punctatus</topic><topic>Injections, Intraperitoneal</topic><topic>LIVER</topic><topic>Male</topic><topic>Medical sciences</topic><topic>METABOLISM</topic><topic>METABOLISME</topic><topic>METABOLISMO</topic><topic>METABOLITE</topic><topic>METABOLITES</topic><topic>METABOLITOS</topic><topic>METHOXYCHLOR</topic><topic>Methoxychlor - administration & dosage</topic><topic>Methoxychlor - pharmacokinetics</topic><topic>Methoxychlor - pharmacology</topic><topic>METHOXYCHLORE</topic><topic>METOXICLORO</topic><topic>MICROSOMES</topic><topic>Microsomes, Liver - drug effects</topic><topic>Microsomes, Liver - enzymology</topic><topic>OESTROGENE</topic><topic>OESTROGENS</topic><topic>ORGANITE CELLULAIRE</topic><topic>ORGANULOS CITOPLASMICOS</topic><topic>OXIDOREDUCTASES</topic><topic>OXIDORREDUCTASAS</topic><topic>OXYDOREDUCTASE</topic><topic>Pesticides, fertilizers and other agrochemicals toxicology</topic><topic>SERUM SANGUIN</topic><topic>SUERO SANGUINEO</topic><topic>Toxicology</topic><topic>UNSPECIFIC MONOOXYGENASE</topic><topic>VITELLOGENINE</topic><topic>VITELLOGENINS</topic><topic>Vitellogenins - blood</topic><topic>VITELOGENINA</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Schlenk, Daniel</creatorcontrib><creatorcontrib>Stresser, David M.</creatorcontrib><creatorcontrib>McCants, John C.</creatorcontrib><creatorcontrib>Nimrod, Alison C.</creatorcontrib><creatorcontrib>Benson, William H.</creatorcontrib><collection>AGRIS</collection><collection>Pascal-Francis</collection><collection>Medline</collection><collection>MEDLINE</collection><collection>MEDLINE (Ovid)</collection><collection>MEDLINE</collection><collection>MEDLINE</collection><collection>PubMed</collection><collection>CrossRef</collection><collection>Toxicology Abstracts</collection><collection>Water Resources Abstracts</collection><collection>Environmental Sciences and Pollution Management</collection><collection>ASFA: Aquatic Sciences and Fisheries Abstracts</collection><collection>Aquatic Science & Fisheries Abstracts (ASFA) 3: Aquatic Pollution & Environmental Quality</collection><collection>Aquatic Science & Fisheries Abstracts (ASFA) Professional</collection><collection>MEDLINE - Academic</collection><jtitle>Toxicology and applied pharmacology</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Schlenk, Daniel</au><au>Stresser, David M.</au><au>McCants, John C.</au><au>Nimrod, Alison C.</au><au>Benson, William H.</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Influence of β-Naphthoflavone and Methoxychlor Pretreatment on the Biotransformation and Estrogenic Activity of Methoxychlor in Channel Catfish (Ictalurus punctatus)</atitle><jtitle>Toxicology and applied pharmacology</jtitle><addtitle>Toxicol Appl Pharmacol</addtitle><date>1997-08-01</date><risdate>1997</risdate><volume>145</volume><issue>2</issue><spage>349</spage><epage>356</epage><pages>349-356</pages><issn>0041-008X</issn><eissn>1096-0333</eissn><coden>TXAPA9</coden><abstract>The organochlorine pesticide methoxychlor [1,1,1-trichloro-2,2-bis(4-methoxyphenyl) ethane] (MXC) has been classified as a proestrogen in mammals and fish, requiring demethylation prior to eliciting estrogenic activity or binding to the estrogen receptor. While microsomal demethylation occurs readily in the liver of fish, little is known about the enzyme(s) responsible or the effect of cytochrome P450 (CYP) inducers, other than those of CYP1A and CYP2K, on biotransformation. Consequently, male channel catfish were pretreated with MXC or β-naphthoflavone (BNF), alone and in combination, to determine their effects on CYP protein expression, MXC biotransformation by hepatic microsomes, microsomal protein binding, and MXC estrogenic activity as determined by serum vitellogenin and 17β-estradiol. Liver microsomes of both treated and untreated mature male catfish catalyzed formation of monodemethylated MXC, bisdemethylated MXC, as well as ring-hydroxylated metabolites. Pretreatment with BNF did not affect MXC metabolite profiles, overall rates of MXC biotransformation, or microsomal proteins recognized by anti-trout CYP2K1, but had the expected effect of inducing CYP1A and associated ethoxyresorufinO-deethylase activity. By contrast, pretreatment with MXC, alone or in combination with BNF, significantly reduced rates of MXC biotransformation and binding to liver microsomal protein. MXC/BNF cotreatment followed by MXC significantly induced serum vitellogenin, whereas MXC treatment alone led to a nonsignificant increase in vitellogenin and a significant increase in serum 17β-estradiol. Thus, estrogenic activity elicited by cotreatment with MXC and BNF can occur despite diminished capacity of liver microsomes to catalyze formation of estrogenic demethylated metabolites or metabolites that bind microsomal protein. Possible mechanisms of MXC-induced attenuation of CYP-dependent metabolism are discussed.</abstract><cop>San Diego, CA</cop><pub>Elsevier Inc</pub><pmid>9266808</pmid><doi>10.1006/taap.1997.8194</doi><tpages>8</tpages></addata></record> |
| fulltext | fulltext |
| identifier | ISSN: 0041-008X |
| ispartof | Toxicology and applied pharmacology, 1997-08, Vol.145 (2), p.349-356 |
| issn | 0041-008X 1096-0333 |
| language | eng |
| recordid | cdi_proquest_miscellaneous_79223621 |
| source | MEDLINE; Access via ScienceDirect (Elsevier) |
| subjects | ACTIVADOR ENZIMATICO ACTIVATEUR D'ENZYME ACTIVIDAD ENZIMATICA ACTIVITE ENZYMATIQUE Animals beta-Naphthoflavone - administration & dosage beta-Naphthoflavone - pharmacology Biological and medical sciences Biotransformation - drug effects BLOOD SERUM CITOCROMO P450 Cytochrome P-450 Enzyme System - biosynthesis CYTOCHROME P450 CYTOPLASMIC ORGANELLES ENZYME ACTIVATORS Enzyme Induction - drug effects ENZYMIC ACTIVITY Estradiol - blood ESTROGENIC PROPERTIES ESTROGENOS Estrogens - blood FLAVONOIDE FLAVONOIDES FLAVONOIDS FOIE Freshwater HIGADO Ictaluridae ICTALURUS Ictalurus punctatus Injections, Intraperitoneal LIVER Male Medical sciences METABOLISM METABOLISME METABOLISMO METABOLITE METABOLITES METABOLITOS METHOXYCHLOR Methoxychlor - administration & dosage Methoxychlor - pharmacokinetics Methoxychlor - pharmacology METHOXYCHLORE METOXICLORO MICROSOMES Microsomes, Liver - drug effects Microsomes, Liver - enzymology OESTROGENE OESTROGENS ORGANITE CELLULAIRE ORGANULOS CITOPLASMICOS OXIDOREDUCTASES OXIDORREDUCTASAS OXYDOREDUCTASE Pesticides, fertilizers and other agrochemicals toxicology SERUM SANGUIN SUERO SANGUINEO Toxicology UNSPECIFIC MONOOXYGENASE VITELLOGENINE VITELLOGENINS Vitellogenins - blood VITELOGENINA |
| title | Influence of β-Naphthoflavone and Methoxychlor Pretreatment on the Biotransformation and Estrogenic Activity of Methoxychlor in Channel Catfish (Ictalurus punctatus) |
| url | https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2024-12-02T17%3A57%3A40IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-proquest_cross&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=Influence%20of%20%CE%B2-Naphthoflavone%20and%20Methoxychlor%20Pretreatment%20on%20the%20Biotransformation%20and%20Estrogenic%20Activity%20of%20Methoxychlor%20in%20Channel%20Catfish%20(Ictalurus%20punctatus)&rft.jtitle=Toxicology%20and%20applied%20pharmacology&rft.au=Schlenk,%20Daniel&rft.date=1997-08-01&rft.volume=145&rft.issue=2&rft.spage=349&rft.epage=356&rft.pages=349-356&rft.issn=0041-008X&rft.eissn=1096-0333&rft.coden=TXAPA9&rft_id=info:doi/10.1006/taap.1997.8194&rft_dat=%3Cproquest_cross%3E16104592%3C/proquest_cross%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_pqid=16104592&rft_id=info:pmid/9266808&rft_els_id=S0041008X97981941&rfr_iscdi=true |