Publication in refereed journal
香港中文大学研究人员 ( 现职)
| 陈锦荣先生 (化学病理学系) |
| 潘力行教授 (化学病理学系) |
全文
| 数位物件识别号 (DOI) http://dx.doi.org/10.1016/j.steroids.2006.07.008 |
引用次数
Web of Sciencehttp://aims.cuhk.edu.hk/converis/portal/Publication/0WOS source URL
其它资讯
摘要Nitric oxide (NO) supposedly derived via L-arginine-NO synthase (NOS) pathway has been implicated in inhibiting steroidogenesis by binding the heme moiety of steroidogenic enzymes. Previously, nitrite, and to a lesser extent nitrate ions inhibited steroidogenesis via NO by hitherto unknown reduction mechanism. Recently, a putative mammalian nitrite reductase activity ascribed to complex III of mitochondrial respiratory chain complexes (MRCC) has been reported, where MRCC inhibitors reduced NO production from nitrite variably. We thus studied the effects of MRCC inhibitors on testosterone production in mouse Leydig tumor cells (MLTC-1) without (basal) or with human chorionic gonadotropin (hCG) stimulation. In stimulated MLTC-1, MRCC inhibitors decreased testosterone production, order being: complex III (antimycin A and myxothiazol) > complex I (rotenone) > complex II (thenoyltrifluoroacetone), while cAMP production increased inversely. In unstimulated MLTC-1, MRCC inhibitors in same order, increased basal testosterone production, which correlated inversely with the percentage inhibition of NO production, with one exception; while antimycin A did not inhibit NO production in the nitrite reductase study mentioned above, it increased basal testosterone production in the present study. While MLTC-1 expressed mRNA for endothelial and neuronal, but not inducible NOS, various stimulators and inhibitors of L-arginine-NOS pathway had no effect on basal testosterone production in MLTC-1 or fresh Balb/c Leydig cells. Moreover, hCG increased nitrate uptake into MLTC1, which suggests the gonadotropin aids nitrite and nitrate ions in their steroidogenesis inhibitory activity. In conclusion, this study supports the existence of a surrogate mammalian nitrite reductase and the dormancy of L-arginine-NOS pathway in MLTC-1.
着者Panesar NS, Chan KW
期刊名称STEROIDS
出版年份2http://aims.cuhk.edu.hk/converis/portal/Publication/0http://aims.cuhk.edu.hk/converis/portal/Publication/06
月份11
日期1
卷号71
期次11-12
出版社ELSEVIER SCIENCE INC
页次984 - 992
国际标準期刊号http://aims.cuhk.edu.hk/converis/portal/Publication/0http://aims.cuhk.edu.hk/converis/portal/Publication/039-128X
电子国际标準期刊号1878-5867
语言英式英语
关键词chloride channel; gonadotropins; nitrate uptake; nitric oxide; SPQ fluorescence; steroidogenesis
Web of Science 学科类别Biochemistry & Molecular Biology; BIOCHEMISTRY & MOLECULAR BIOLOGY; Endocrinology & Metabolism; ENDOCRINOLOGY & METABOLISM
