Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, 373, Bloco F, Sala F2-027, Cidade Universitária, Rio de Janeiro, RJ 21941-902, Brasil.
Calcif Tissue Int. 2012 Sep;91(3):186-95. doi: 10.1007/s00223-012-9625-2. Epub 2012 Jul 18.
The aim of this study was to evaluate the strontium incorporation into specific bones and teeth of rats treated with strontium ranelate. The relative strontium levels [Sr/(Ca + Sr) ratio] were obtained by synchrotron radiation micro X-ray fluorescence. The incisor teeth were further examined by energy dispersive X-ray spectroscopy (EDS) in a scanning electron microscope. The isolated mineral phase was investigated by EDS in a transmission electron microscope and X-ray diffraction. The strontium content was markedly increased in animals treated with strontium ranelate, with different incorporation levels found among specific bones, regions within the same bone and teeth. The highest strontium levels were observed in the iliac crest, mandible and calvaria, while the lowest were observed in the femoral diaphysis, lumbar vertebrae, rib and alveolar bone. The strontium content was higher in the femoral neck than in the diaphysis. The strontium levels also varied within the alveolar bone. High levels of strontium were found in the incisor tooth, with values similar to those in the iliac crest. Strontium was observed in both enamel and dentin. The strontium content of the molar tooth was negligible. Strontium was incorporated into the mineral substance, with up to one strontium replacing one out of 10 calcium ions within the apatite crystal lattice. The mineral from treated animals presented increased lattice parameters, which might be associated to their bone strontium contents. In conclusion, the incorporation of strontium occurred in different levels into distinct bones, regions within the same bone and teeth of rats treated with strontium ranelate.
本研究旨在评估雷奈酸锶治疗大鼠后锶在特定骨骼和牙齿中的掺入情况。利用同步辐射微 X 射线荧光法获得相对锶水平[Sr/(Ca+Sr) 比值]。在扫描电子显微镜中，通过能量色散 X 射线光谱（EDS）进一步检查门齿。在透射电子显微镜和 X 射线衍射中，通过 EDS 研究分离的矿物相。用雷奈酸锶治疗的动物的锶含量明显增加，在特定骨骼、同一骨骼内的不同区域以及牙齿中发现了不同的掺入水平。髂嵴、下颌骨和颅骨的锶含量最高，而股骨骨干、腰椎、肋骨和牙槽骨的锶含量最低。股骨颈的锶含量高于骨干。牙槽骨内的锶含量也存在差异。门齿中的锶含量较高，与髂嵴中的值相似。锶存在于釉质和牙本质中。磨牙中的锶含量可以忽略不计。锶掺入到矿物质中，在磷灰石晶格中，每 10 个钙离子中就有一个被锶取代。来自治疗动物的矿物质呈现出晶格参数增加，这可能与其骨骼中的锶含量有关。总之，锶在雷奈酸锶治疗的大鼠的不同骨骼、同一骨骼内的不同区域以及牙齿中以不同水平掺入。
