Abstract:
:Thebaine, an intermediate of morphine biosynthesis in the poppy plant, Papaver somniferum, was transformed to oripavine, codeine, and morphine by rat liver, kidney, and brain microsomes in the presence of an NADPH-generating system. The formation of morphine, codeine, and oripavine was identified by a specific RIA, HPLC, and GCMS. Thebaine also gave rise to four other compounds, which for the moment are unidentified. NADH dramatically increased the formation of both codeine and morphine when used together with an NADPH-generating system, especially in liver microsomes. NADPH is essential in the formation of oripavine from thebaine and morphine from codeine, while NADH is critical in the conversion of thebaine to codeine and from oripavine to morphine. Carbon monoxide or SKF 525A inhibited the conversion, indicating a role of cytochrome P-450. These results provide evidence for the enzymatic in vitro conversion by mammalian tissues of thebaine to morphine. The pathway is similar to that which exists in plants.
journal_name
Proc Natl Acad Sci U S Aauthors
Kodaira H,Spector Sdoi
10.1073/pnas.85.4.1267subject
Has Abstractpub_date
1988-02-01 00:00:00pages
1267-71issue
4eissn
0027-8424issn
1091-6490journal_volume
85pub_type
杂志文章abstract::Targeted drug delivery critically depends on the binding selectivity of cargo-transporting colloidal particles. Extensive theoretical work has shown that two factors are necessary to achieve high selectivity for a threshold receptor density: multivalency and weak interactions. Here, we study a model system of DNA-coat...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2011-10-11 00:00:00
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更新日期:2012-05-01 00:00:00