LC-ELECTROSPRAY QUADRUPOLE ION TRAP MASS SPECTROMETER

申请资金用于购买液相色谱-电喷雾四极离子阱质谱仪（LC-ESI-Q-IT MS）。之所以选择LC-ESI- Q-IT质谱，是因为它具有以下几个关键的工作特性：1)高检测灵敏度（pmol-fmol）， 2) HPLC - MS在线耦合，3)优秀的MST能力，4)高通量和自动化程度。该仪器将由美国国立卫生研究院支持的孟菲斯田纳西大学和孟菲斯圣裘德儿童研究医院的一组研究人员共享。所要求的LC-ESI-Q-IT质谱是目前MALDI-TOF仪器的补充，并提供MALDI-TOF分析的替代方案。LC-ESI-Q-IT仪器将用于以下研究项目：蛋白质组学：(i)研究与特发性腰痛相关的人脑脊液（CSF）中阿片神经肽能系统的改变；（ii）人垂体肿瘤组织中阿片系统的分析；(3)研究活化人巨噬细胞的蛋白酶，以增强对微生物和肿瘤细胞的杀伤作用。定量：(i)人脑垂体和脑脊液中的神经肽；（ii）小鼠脑脊液微透析液中的促肾上腺皮质激素释放激素（在尼古丁对神经元功能影响的研究中）；（iii）大鼠下丘脑神经肽Y和食欲素（用于研究尼古丁引起的食物摄入刺激因子的变化）；（iv）羊血浆中的合成阿片肽类似物（用于产科镇痛药物的研究）。生物活性化合物的结构：(i)参与巨噬细胞活化的细菌细胞壁成分（脂多糖和糖肽）；（ii）血源性磷脂生长因子。蛋白质特性：(i)参与花生四烯酸在血管中释放的酶；（ii）野生型和突变型硫嘌呤甲基转移酶（用于研究TPMT的遗传多态性）；（iii）错配修复蛋白（研究它们参与硫嘌呤细胞毒性的测定）。这些研究项目的成功完成将进一步加深对与人类健康有关的几个领域的理解，如神经肽在疾病中的作用，吸烟的影响。大脑功能，免疫系统抵抗感染的能力，以及使用硫嘌呤治疗儿童癌症。

Funds are requested to purchase a liquid chromatograph-electrospray quadrupole ion trap mass spectrometer (LC-ESI-Q-IT MS). The LC-ESI- Q-IT MS is selected because it possesses several critical operating features: l) high detection sensitivity (pmol-fmol), 2) on-line coupling of HPLC to MS, 3) excellent MST capabilities, and 4) high throughput and automation. This instrument will be shared by a group of NIH-supported researchers at the University of Tennessee, Memphis, and at the St. Jude Children's Research Hospital, Memphis. The requested LC-ESI-Q-IT MS is needed to complement the current MALDI-TOF instrument and to provide an alternative to MALDI-TOF analysis. The LC-ESI-Q-IT instrument will be employed in the following research programs: Proteomics: (i) studies of the alterations of opioid neuropeptidergic systems in human cerebrospinal fluid (CSF), that are associated with idiopathic low back pain; (ii) analysis of the opioid systems in human pituitary tumor tissue; and (iii) investigation of the proteases involved in the activation of human macrophages for enhanced killing of microbes and tumor cells. Quantification: (i) neuropeptides in human pituitary and in human CSF; (ii) corticotropin-releasing hormone in the microdialysates of mouse CSF (in the investigation of the effects of nicotine on neuronal functions); (iii) neuropeptide Y and orexins in rat hypothalamus (for the study of the nicotine-induced changes in food intake stimulators); and (iv) synthetic opioid peptide analogs in ovine plasma (in the study of pain-reducing drugs for use in obstetrics). Structures of biologically active compounds: (i) bacterial cell wall constituents (lipopolysaccharides and glycopeptides) involved in macrophage activation; and (ii) blood-derived phospholipid growth factors. Protein characterization: (i) enzymes involved in arachidonic acid release in blood vessels; (ii) wild-type and mutant forms of thiopurine methyltransferase (for the investigation of the genetic polymorphism of TPMT); and (lii) mismatch repair proteins (in the study of their involvement in the determination of thiopurine cytotoxicity). Successful completion of these research programs will further the understanding in several areas related to human health, such as the role of neuropeptides in disease, effects of smoking.on brain functions, ability of the immune system to fight infection, and the use of thiopurines for the treatment of childhood cancer.