| Autor: |
Kang-Yi Chou, Cheng-Yi Huang, Hsuch-Ching Chiang |
| Rok vydání: |
1990 |
| Předmět: |
|
| Zdroj: |
European Journal of Pharmacology. 183:x |
| ISSN: |
0014-2999 |
| DOI: |
10.1016/0014-2999(90)94046-z |
| Popis: |
Fonnosanin c is a steroidal glycoside isolated from Paris fonnosana Hayata. It has been known from the previous studies, the growth of solid MH134 mice hepatoma was retarded by 1-2.5 mg/kg Fonnosanin c, and also significant regression in tumor SK-OV-3 (ovary) and HT-29 (colon) was induced by PF-3. The biotransfonnation of fonnosanin c by hepatic cytochrome P-450 has been investigated. The hepatic microsomal cytochrome P450 enzyme system is capable of binding and metabolising formosanin c which is shown to bind the type II site (oxygen binding site) of the enzyme at the concentrations of 150 μM. The apparent binding constants (Ks) was 78μM. The observed effect of induction of phenobarbital on A max and V max suggests that several of the multiple forms of cytochrome P450 bind formosanin c. The incubation of Formosanin c with hepatic microsomes of rats in the presense of an NADPH-generating system led to decrease of cytochrome P-450 measured by its carbon monoxide difference spectra, and the decrease was enhanced by phenobarbital treatment. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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