Dudek R, Conforto A, Pinto V, Bing R J
Department of Experimental Cardiology, Huntington Medical Research Institutes, Pasadena, Calif. 91101.
Pharmacology. 1994 Jun;48(6):374-9. doi: 10.1159/000139203.
Amphiphiles are known to modulate the activity of ATPase, phospholipase A2, adenylate and guanylate cyclase amongst others and relax vascular smooth muscle. The effect of two amphiphiles, lysophosphatidylcholine (LPC) and digitonin on the activity of nitric oxide synthase (NOS), as measured by conversion of radiolabeled L-arginine to L-citrulline, has been studied. Neither digitonin (0.01 mmol/l) nor LPC (0.01 mmol/l) influenced NOS activity in endothelial cell homogenates. Digitonin but not LPC stimulated NOS in intact endothelial cells. NOS activity was markedly inhibited by L- but not by D-omega-nitroarginine (D-NNA, 0.1 mmol/l). L-NNA or D-NNA data demonstrate no effect of amphiphiles on isolated NOS. NOS activation may occur as a result of detergent action on the membrane.
已知两亲性分子可调节ATP酶、磷脂酶A2、腺苷酸环化酶和鸟苷酸环化酶等的活性，并使血管平滑肌松弛。研究了两种两亲性分子溶血磷脂酰胆碱（LPC）和洋地黄皂苷对一氧化氮合酶（NOS）活性的影响，通过将放射性标记的L-精氨酸转化为L-瓜氨酸来测定。洋地黄皂苷（0.01 mmol/L）和LPC（0.01 mmol/L）均不影响内皮细胞匀浆中的NOS活性。洋地黄皂苷而非LPC刺激完整内皮细胞中的NOS。L-ω-硝基精氨酸（L-NNA，0.1 mmol/L）可显著抑制NOS活性，而D-ω-硝基精氨酸（D-NNA，0.1 mmol/L）则无此作用。L-NNA或D-NNA的数据表明两亲性分子对分离的NOS无影响。NOS的激活可能是由于去污剂对膜的作用所致。
