caa a22 4500 397558678 CHVBK 20180308164810.0 cr unu---uuuuu 161202e199611 xx s 000 0 eng 10.1093/oxfordjournals.jbchem.a021516 doi (NATIONALLICENCE)oxford-10.1093/oxfordjournals.jbchem.a021516 Lanosterol 14-Demethylase Activity Expressed in Rat Brain Microsomes [Elektronische Daten] [Yuri Aoyama, Tadao Horiuchi, Yuzo Yoshida] The occurrence of sterol 14-demethylase in rat brain microsomes was confirmed. The brain microsomes from adult rats converted lanosterol into its 14-demethylated products, 4,4-dimethylcholesta-8,24-dienol, and 4,4-dimethylcholesta-8,14,24-trienol, in the presence of NADPH and molecular oxygen. This metabolism of lanosterol was inhibited by carbon monoxide and ketoconazole, a potent inhibitor of sterol 14-demethylase P450 (P45014DM or CYP51). These facts indicated the occurrence of lanosterol 14-demethylation in rat brain microsomes and its dependency on P45014DM. A representative value of the lanosterol demethylase activity of the brain microsomes was 8.4 pmol/min/mg protein or 640 pmol/min/nmol of total P450. The former was about one-thirteenth of the corresponding value observed with liver microsomes from the same rats, while the latter was 4-times higher than the corresponding value obtained with the liver microsomes. This fact suggested that the ratio of P45014DM to other P450 species was higher in brain than in liver. Lanosterol 14-demethylation is situated at the root of the sterol-biosynthetic branch of the mevalonic acid pathway. Therefore, the present finding enzymologically supports the existence of the sterol biosynthetic pathway in brain. © 1996 BY THE JOURNAL OF BIOCHEMISTRY Regular Papers nationallicence brain nationallicence cholesterol nationallicence P450 nationallicence sterol synthesis nationallicence sterol 14-demethylase nationallicence Aoyama Yuri Department of Bioengineering, Faculty of Engineering, Soka University Tangi-cho, Hachioji, Tokyo 192 aut Horiuchi Tadao Department of Bioengineering, Faculty of Engineering, Soka University Tangi-cho, Hachioji, Tokyo 192 aut Yoshida Yuzo School of Pharmaceutical Sciences, Mukogawa Women's University Koshien Kyuban-cho, Nishinomiya, Hyogo 663 aut The Journal of Biochemistry Oxford University Press 120/5(1996-11), 982-986 0021-924X 120:5<982 1996 120 jbchem https://doi.org/10.1093/oxfordjournals.jbchem.a021516 text/html Onlinezugriff via DOI 1 other jats NATIONALLICENCE 856 40 https://doi.org/10.1093/oxfordjournals.jbchem.a021516 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Aoyama Yuri Department of Bioengineering, Faculty of Engineering, Soka University Tangi-cho, Hachioji, Tokyo 192 aut NATIONALLICENCE 700 1- Horiuchi Tadao Department of Bioengineering, Faculty of Engineering, Soka University Tangi-cho, Hachioji, Tokyo 192 aut NATIONALLICENCE 700 1- Yoshida Yuzo School of Pharmaceutical Sciences, Mukogawa Women's University Koshien Kyuban-cho, Nishinomiya, Hyogo 663 aut NATIONALLICENCE 773 0- The Journal of Biochemistry Oxford University Press 120/5(1996-11), 982-986 0021-924X 120:5<982 1996 120 jbchem Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford