Sunano S
Reseach Institute of Hypertension, Kinki University, Osaka-Sayama.
Nihon Heikatsukin Gakkai Zasshi. 1988 Jun;24(3):147-58. doi: 10.1540/jsmr1965.24.147.
Vanadate is a trace element in biological tissues which has inhibitory actions on various enzymes. It inhibits Na, K-ATPase of smooth muscle membrane. Ca-ATPase and Ca-uptake of membranous systems of smooth muscle cells are also inhibited by vanadate. Vanadate induces contractions in various smooth muscles. These contractions are not mediated by the inhibition of Na, K-ATPase. The contractions are induced by both the influxed Ca from extracellular space and the released Ca from intracellular binding sites. In certain smooth muscles, the changes in electrical activities are also involved. These effects of vanadate are not mediated by the release of transmitter from intrinsic nerves. The direct actions on contractile proteins is inhibitory and cannot be the cause of the contraction. Thus, vanadate induces contraction in various smooth muscles, by increasing Ca permeability of cell membrane and by releasing intracellular bound Ca. In addition, the inhibition of Ca-pump may also be involved in the initiation or potentiation of contraction by vanadate. The degree of each action varies among various smooth muscles.
钒酸盐是生物组织中的一种微量元素，对多种酶具有抑制作用。它抑制平滑肌膜的钠钾 -ATP酶。钒酸盐还抑制平滑肌细胞膜系统的钙 -ATP酶和钙摄取。钒酸盐可诱导多种平滑肌收缩。这些收缩并非由钠钾 -ATP酶的抑制介导。收缩是由细胞外空间流入的钙和细胞内结合位点释放的钙共同引起的。在某些平滑肌中，电活动的变化也参与其中。钒酸盐的这些作用并非由内在神经释放递质介导。对收缩蛋白的直接作用是抑制性的，不可能是收缩的原因。因此，钒酸盐通过增加细胞膜的钙通透性和释放细胞内结合的钙来诱导多种平滑肌收缩。此外，钙泵的抑制也可能参与钒酸盐引起的收缩的起始或增强。每种作用的程度在不同的平滑肌中有所不同。
