De Boland A R, Gallego S, Boland R
Biochim Biophys Acta. 1983 Sep 7;733(2):264-73. doi: 10.1016/0005-2736(83)90531-x.
The effects of vitamin D-3 on calcium and phosphate transport in skeletal muscle plasma membranes were studied. Sarcolemma vesicles were isolated from vitamin D-deficient and vitamin D-treated (one week) chicks by sucrose density gradient centrifugation of a crude muscle plasma membrane fraction. Measurement of (Na+ + K+)-ATPase activity, cholesterol to phospholipid molar ratios and levels of intracellular marker enzymes showed a high degree of purification of the preparations. Administration of vitamin D-3 significantly increased active Ca2+ and phosphate uptake into the vesicles. The efflux of both ions from preloaded vesicles was only slightly altered by the sterol. Ca2+-ATPase activity was higher in sarcolemma from treated animals. This confirms that the effects of vitamin D-3 on calcium transport are related to the Ca2+ pump and not to the passive permeability properties of the membrane. No changes in the protein composition of vesicles from both experimental groups were observed. However, treatment with vitamin D-3 increased sphingomyelin and phosphatidylcholine concentrations. These changes in lipid structure may play a role in the effects of vitamin D-3 on transport characteristics of sarcolemma.
研究了维生素D-3对骨骼肌质膜中钙和磷转运的影响。通过对粗制肌质膜部分进行蔗糖密度梯度离心，从维生素D缺乏和经维生素D处理（一周）的雏鸡中分离出肌膜囊泡。对（Na+ + K+）-ATP酶活性、胆固醇与磷脂摩尔比以及细胞内标记酶水平的测量表明，制备物得到了高度纯化。给予维生素D-3显著增加了囊泡对活性Ca2+和磷的摄取。预加载囊泡中这两种离子的流出仅略有改变。经处理动物的肌膜中Ca2+-ATP酶活性较高。这证实了维生素D-3对钙转运的影响与Ca2+泵有关，而与膜的被动通透性无关。未观察到两个实验组囊泡蛋白质组成的变化。然而，维生素D-3处理增加了鞘磷脂和磷脂酰胆碱的浓度。脂质结构的这些变化可能在维生素D-3对肌膜转运特性的影响中起作用。
