Ichihara K, Tanaka C
Department of Biochemistry, Kawasaki Medical School, Kurashiki, Japan.
Biochem Biophys Res Commun. 1987 Dec 16;149(2):482-7. doi: 10.1016/0006-291x(87)90393-7.
Dilauroylphosphatidylcholine caused a marked increase in progesterone 5 alpha-reductase activity solubilized from rat liver microsomes, whereas naturally occurring phosphatidylcholines from biological sources as well as dioleoylphosphatidylcholine had not effect on the activity. Therefore, the stimulatory effect of phospholipids normally found in rat liver microsomes was examined. The lipid extracts were prepared from the fraction which was freed from 5 alpha-reductase activity by DEAE-cellulose chromatography, and found to exhibit a strong stimulatory effect. The lipid extracts were then separated into phosphatidylserine, phosphatidylcholine and phosphatidylethanolamine by chromatography on silicic acid column and preparative thin-layer plate. Among these endogenous phospholipids, only phosphatidylserine stimulated the 5 alpha-reductase, suggesting that the lipid requirement is specific for phosphatidylserine in steroid 5 alpha-reductase from liver microsomes.
二月桂酰磷脂酰胆碱使从大鼠肝脏微粒体中溶解的孕酮5α-还原酶活性显著增加，而生物来源的天然磷脂酰胆碱以及二油酰磷脂酰胆碱对该活性没有影响。因此，对大鼠肝脏微粒体中通常存在的磷脂的刺激作用进行了研究。脂质提取物是从通过DEAE-纤维素色谱法去除5α-还原酶活性的部分制备的，发现其具有很强的刺激作用。然后通过在硅酸柱和制备性薄层板上进行色谱法将脂质提取物分离为磷脂酰丝氨酸、磷脂酰胆碱和磷脂酰乙醇胺。在这些内源性磷脂中，只有磷脂酰丝氨酸刺激5α-还原酶，这表明肝脏微粒体中类固醇5α-还原酶对磷脂的需求对磷脂酰丝氨酸具有特异性。
