title: Immunohistochemical detection of human placental cytochrome P-450-associated mono-oxygenase system inducible by maternal cigarette smoking.
abstract: Several xenobiotic-metabolizing mono-oxygenase activities, in conjunction with the immunohistochemical localization of the respective cytochrome P-450 forms, were investigated in placentae from smoking and non-smoking women. The antibodies used in the immunohistochemical analyses were monoclonal antibodies (MAbs) 1-7-1 and 2-66-3, prepared against the 3-methylcholanthrene-induced and phenobarbital-induced rat liver P-450, respectively. The mono-oxygenase activities were higher in placental microsomes from smokers, although no difference was observed in microsomal P-450 content. A distinct positive staining with MAb 1-7-1 was detectable in the trophoblastic layer of all placentae from smokers. In placentae from non-smokers, minimal cytoplasmic staining was observed in large villi in a few trophoblastic cells. The staining reaction was negative when MAb 2-66-3 or non-specific antibody were used. These results demonstrate that maternal cigarette smoking induces in the trophoblastic layer of the placenta a cytochrome P-450 form which is detectable immunohistochemically with the monoclonal antibody to 3-methylcholanthrene-inducible P-450 in rat liver.
mesh_terms: D000911:Antibodies, Monoclonal; D001189:Aryl Hydrocarbon Hydroxylases / Q000378:metabolism; D002824:Chorionic Villi / Q000201:enzymology*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008861:Microsomes / Q000201:enzymology; D010105:Oxygenases / Q000378:metabolism*; D011247:Pregnancy / Q000378:metabolism*; D012907:Smoking / Q000009:adverse effects* / Q000378:metabolism; D014327:Trophoblasts / Q000201:enzymology*
chemical_list: D000911:Antibodies, Monoclonal; D003577:Cytochrome P-450 Enzyme System; D010105:Oxygenases; D001189:Aryl Hydrocarbon Hydroxylases