Perrella F W
Medical Products Department, E. I. Du Pont de Nemours & Co., Glenolden, Pennsylvania 19036.
Biochem Biophys Res Commun. 1990 Jan 30;166(2):715-22. doi: 10.1016/0006-291x(90)90868-n.
Phosphoinositide phospholipase C activity was investigated in human melanoma grown as solid tumor xenografts in nude mice. The enzyme was dependent on calcium for activity and was stimulated by the detergent deoxycholate. The pH optimum was 5.5 in the absence of detergent, and in the presence of deoxycholate two pH maxima were present, 5.5 and 7.2. Phospholipase C activity was inhibited by the sulfhydryl reagent dithionitrobenzoate with an IC50 in the micromolar range. Phospholipase C activity was distributed widely in mouse tissues. The enzyme showed a progressive increase in activity from heart, liver, lung, colon, spleen, to brain tissue. Mouse and human melanomas grown as solid tumors had higher phospholipase C activity than mouse brain. The relatively high activity of this enzyme in melanoma may suggest a biological role for phospholipase C in solid tumor growth.
对在裸鼠体内生长为实体瘤异种移植物的人黑色素瘤中的磷酸肌醇磷脂酶C活性进行了研究。该酶的活性依赖于钙，并受到去污剂脱氧胆酸盐的刺激。在没有去污剂的情况下，最适pH为5.5，在有脱氧胆酸盐存在时，有两个pH最大值，即5.5和7.2。磷脂酶C活性受到巯基试剂二硫代硝基苯甲酸的抑制，其IC50在微摩尔范围内。磷脂酶C活性在小鼠组织中广泛分布。该酶的活性从心脏、肝脏、肺、结肠、脾脏到脑组织呈逐渐增加趋势。作为实体瘤生长的小鼠和人黑色素瘤的磷脂酶C活性高于小鼠脑。该酶在黑色素瘤中相对较高的活性可能表明磷脂酶C在实体瘤生长中具有生物学作用。
