生物活性

• 描述Ruthenium red may be a new type of CaM antagonist that inhibits the binding of Ca2+ to CaM and thereby inhibits Ca(2+)-CaM-dependent enzymes and smooth muscle contraction competitively with respect to Ca2+. The Ca(2+)-calmodulin (CaM)-dependent activation of myosin light chain kinase is inhibited by ruthenium red competitively with respect to Ca2+, with a Ki value of 8.6 microM. The binding of Ca2+ to CaM is inhibited by micromolar concentrations of ruthenium red. In the absence of Ca2+, CaM has two binding sites for ruthenium red with the dissociation constants of 0.36 and 8.7 microM, respectively. Moreover, ruthenium red inhibits Ca(2+)-induced contraction of depolarized vascular smooth muscle in a competitive manner with respect to Ca2+^[1]. Ruthenium red inhibited Ca2+ binding to the sarcoplasmic reticulum protein, calsequestrin, immobilized on Sepharose 4B. Furthermore, ruthenium red bound to calsequestrin with high affinity (Kd = 0.7 microM; Bmax = 218 nmol/mg protein). Ruthenium red stained both the erythrocyte Band 3 anion transporter and the Ca2(+)-ATPase of skeletal muscle sarcoplasmic reticulum. Ruthenium red also stained the EF hand conformation Ca2(+)-binding proteins, calmodulin, troponin C, and S-100^[2]. After the systemic administration of RuR, can be accounted for by the binding of RuR to nerve ending membranes, which results in inhibition of Ca2+ influx through voltage-sensitive calcium channels and the consequent inhibition of neurotransmitter release. On the other hand, the administration of RuR into the cerebrospinal fluid induces intense convulsive activity, and its microinjection into the substantia nigra reticulata or the hippocampus leads to various motor behavior alterations that can be related to hyperexcitability of the neurons of the injected region. In addition, RuR penetrates the neuronal somata present in the area injected and induces cell destruction, which has been interpreted as an excitotoxic action of the dye((Tapia R, Velasco I. Ruthenium red as a tool to study calcium channels, neuronal death and the function of neural pathways. Neurochem Int. 1997;30(2):137‐147|https://www. ncbi.nlm.nih. gov/ pubmed/9017661}}. Ruthenium red has been used to show the ultrastructural detail of bacterial glycocalyces. Ruthenium red has broad utility in the biological sciences, and in combination with lysine, it is an excellent EM stain for enhanced visualization of bacterial glycocalyx from culture or from clinical specimens^[3].
• 临床研究

• NCT号	适应症或疾病	临床期	招募状态	预计完成时间	地点
  NCT00079417	Intraocular Retinoblastoma	Phase 3	Completed	-	United States, California ... more >> Children's Oncology Group Monrovia, California, United States, 91016 United States, Washington Fred Hutchinson Cancer Research Center/University of Washington Cancer Consortium Seattle, Washington, United States, 98109 Collapse <<
  NCT00079417	-	-	Completed	-	-

• 参考文献

• [1] Sasaki T, Naka M, Nakamura F, Tanaka T. Ruthenium red inhibits the binding of calcium to calmodulin required for enzyme activation. J Biol Chem. 1992;267(30):21518‐21523

  [2] Charuk JH, Pirraglia CA, Reithmeier RA. Interaction of ruthenium red with Ca2(+)-binding proteins. Anal Biochem. 1990;188(1):123‐131

  [3] Fassel TA, Edmiston CE Jr. Ruthenium red and the bacterial glycocalyx. Biotech Histochem. 1999;74(4):194‐212