ROLE OF GINGIVAL FLUID POLYAMINES IN PMN MODULATION

中性粒细胞(PMN)是机体防御的重要组成部分 牙周病和其他细菌感染。PMN功能为 受与表面受体结合的配体的调节，这一事件发生在- ATES磷脂酰肌醇水解物和瞬时增加 胞内钙离子。这些细胞内信号相互配合以 动员蛋白激酶C(PKC)，启动多种必要的PMN活性。 领带。最近的证据表明，钙信号显著地 被多胺改变，这种多胺普遍存在于牙周液中 发炎的牙周袋。基于这一证据，我们假设 牙周液多胺可显著延长牙周炎的持续时间。 受体操作的钙动员和_钙依赖的PKC动员。 从而调节许多重要的依赖于钙离子和PKC的中性粒细胞 对细胞外刺激的反应。本提案中详细说明的研究- AL将在体外使用PMN和HL-60细胞来验证这一假设。 用fMLP、C5a和LTB4检测多胺在 行动的三个层次： 1)化学诱导剂诱导的钙动员动力学的调控 提顿。这些影响的机制将通过评估 多胺对肌醇磷脂代谢及细胞功能的影响 Ca~(2+)通道、质膜Ca~(2+)-ATP酶和钙小体。2) 细胞内PKC转位、激活和磷酸化的调控 蛋白质底物。3)钙离子和蛋白激酶C依赖性细胞的调控 活动，包括超氧化物的产生、分泌、肌动蛋白 细胞内PH的聚合、调节和表达 趋化受体。 对宿主防御调制的这一新颖方面的研究将提供一种 更好地了解病原体涉及的复杂机制- SIS与牙周病的进展因为多胺水平是 其他炎症组织的渗出物增加，这些研究是 在其他类型的炎症性疾病中与宿主防御调节相关 放松点。

Neutrophils (PMNs) are an essential component of the host defense in periodontal disease and other bacterial infections. PMN function is modulated by ligand binding to surface receptors, an event which gener- ates phosphoinositide hydrolysis products and transient increases in cytosolic Ca2+. These intracellular signals cooperate with each other to mobilize protein kinase C (PKC) and initiate many essential PMN activi- ties. Recent evidence suggests that Ca2+ signalling is significantly altered by polyamines, which are prevalent in the gingival fluid of inflamed periodontal pockets. Based on this evidence, we hypothesize that gingival fluid polyamines can significantly prolong the duration of both receptor-operated Ca2+ mobilization and_Ca2+-dependent-PKC mobiliza- tion, and thereby modulate many important Ca2+- and PKC-dependent PMN responses to extracellular stimuli. The studies detailed in this propos- al will test this hypothesis in vitro, using PMNs and HL-60 cells stimu- lated with fMLP, C5a, and LTB4 to examine the effects of polyamines at three levels of action: 1) Modulation of the kinetics of chemoattractant-induced Ca2+ mobiliza- tion. The mechanism of these effects will be examined by assessing polyamine effects on phosphoinositide metabolism and on the functions of Ca2+ channels, plasma membrane Ca2+-ATPases, and calciosomes. 2) Modulation of PKC translocation, activation and phosphorylation of cell protein substrates. 3) Modulation of Ca2+ - and PKC-dependent cell activities, including superoxide production, secretion, actin polymerization, regulation of intracellular PH, and expression of chemoattractant receptors. Study of this novel aspect of host defense modulation will provide a better understanding of the complex mechanisms involved in the pathogene- sis and progression of periodontal disease. Since polyamine levels are increased in exudates from other inflamed tissues, these studies are relevant to host defense modulation in other types of inflammatory dis- ease.