显微红外光谱法研究豚鼠膝关节软骨下骨的增龄性改变

应用显微FTIR技术原位分析雌性Hartley豚鼠随月龄增加胫骨关节软骨下骨的化学变化。红外光谱测定三种月龄(1月、2月和3月)豚鼠软骨下3个不同吸收颜色的骨小梁区(a，b，c)和中央骨髓区(d)。结果显示：(1)随月龄增加，骨小梁总面积增加，与正常骨小梁谱图相似的a区减少，d区波形有逐渐向a区发展的趋势。(2)2月龄和3月龄的b和c区AmideⅢ红移以c区红移显著并且变成肩峰，代表核酸和多糖的吸收峰峰强是a区的7倍。(3)三种月龄的c区均出现了β型糖苷键吸收峰。(4)I_AmideⅠ/I_AmideⅡ在2月b区最大，3月各区最小，I_AmideⅢ/I_AmideⅡ 在 2月、3月由a到c依次降低，I_νsPO-₂/I_AmideⅡ在2月、3月的b和c区较相应a区高7倍以上。结果符合骨关节炎不同阶段软骨下骨的组织结构及化学组成的变化规律。初步研究表明，显微光谱成像技术结合FTIR可原位分析不同区域的软骨下骨小梁和骨髓的分子组成，为骨关节炎软骨下骨组织病理学的分子水平研究提供了可靠信息。

FTIR Microspectroscopic Investigation of the Age-Related Changes of Subchondral Bone of the Knee in Guinea Pig

Fourier transform infrared (FTIR) microspectroscopy was applied to in-situ analyse the chemical change of tibial articular subchondral bone of female Hartley guinea pigs with age increase. Three infrared absorption regions (a,b,c) of trabecular bone and central marrow region of the subchondral bone were measured for guinea pigs of different ages (1 months，2 months and 3 months) using the infrared spectrum. Results show that (1) with months increasing, the total area of trabecular bone is increasing, meanwhile, the region a which is similar to normal trabecular bone spectra is decreasing, and region d waveform has the same trend as region a.(2) In the second and third month, region b & c show amide Ⅲ redshift and the red shift in region c shows a shoulder peak, showing the absorption peak intensity on behalf of nucleic acid and polysaccharide in region b & c is 7 times that in region a.(3)β glycosidic bond absorption peak appears at region c in 3 different old pigs.(4) I_amideⅢ/I_amideⅡ is the highest in region b in the second month but lowest in the third month; I_amideⅢ/I_amideⅡ reduces from a to c in the second and third month; I_νsPO-2/I_amideⅡ in region b & c is 7 times higher than region a in the second and third Month. These results are consistent with the regular pattern of change rule of osteoarthritis subchondral bone’s organization structure and chemical composition in different stages . Our primary result illustrated that FTIR microspectroscopy can be used for in-situ analysis of the molecular organization of subchondral trabecular bone and bone marrow. It provides reliable pathology information for osteoarthritis subchondral bone tissue at molecular level.