Jansen Erwin E W, Gibson K Michael, Shigematsu Yosuke, Jakobs Cornelis, Verhoeven Nanda M
Metabolic Unit, Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands.
J Chromatogr B Analyt Technol Biomed Life Sci. 2006 Jan 18;830(2):196-200. doi: 10.1016/j.jchromb.2005.10.053. Epub 2005 Nov 22.
We describe a rapid and sensitive method for the quantification of homocarnosine in physiological fluids, with particular emphasis on cerebrospinal fluid (CSF). Homocarnosine was quantified as the butyl derivative, with (2)H(2)-l-homocarnosine as internal standard. Following deproteinization of CSF samples, supernatants were evaporated to dryness and derivatized with 10% 6M HCl in butanol. Samples were chromatographed on a C(18) column and detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS) operating in the multiple reaction monitoring mode. The intra- and inter-assay variations were 4.6 and 10.9%, respectively. Mean recovery of homocarnosine at two concentrations was 105%. The limit of detection in CSF approximated 20 nmol/L. CSF homocarnosine is age dependent and ranges from <0.02 to 10 micromol/L. Our method is applicable to the analysis of CSF derived from patients with heritable defects in the GABA pathway, patients with homocarnosinosis or serum carnosinase deficiency, and should be applicable to other model systems in order to further explore the biological role and significance of homocarnosine in mammalian systems.
我们描述了一种快速且灵敏的方法，用于定量生理体液中的高肌肽，尤其着重于脑脊液（CSF）。高肌肽被定量为丁基衍生物，以(2)H(2)-L-高肌肽作为内标。脑脊液样品经脱蛋白处理后，将上清液蒸发至干，并用10% 6M盐酸丁醇溶液进行衍生化。样品在C(18)柱上进行色谱分析，并通过在多反应监测模式下运行的液相色谱-串联质谱（LC-MS/MS）进行检测。批内和批间变异分别为4.6%和10.9%。两种浓度下高肌肽的平均回收率为105%。脑脊液中的检测限约为20 nmol/L。脑脊液高肌肽与年龄相关，范围为<0.02至10 μmol/L。我们的方法适用于分析来自γ-氨基丁酸（GABA）途径存在遗传性缺陷的患者、患有高肌肽血症或血清肌肽酶缺乏症患者的脑脊液，并且应该适用于其他模型系统，以便进一步探索高肌肽在哺乳动物系统中的生物学作用和意义。
