[Ca2+]i and Secretory Dynamics in Parotid Acinar Cells

[Ca2]i 和腮腺腺泡细胞的分泌动态

• 批准号: 7932562
• 负责人: David I Yule
• 金额: $ 18.68万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-22 至 2012-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7932562
• 关键词: Acetylcholine; Acinar Cell; Acinus organ component; Address; Adenosine Triphosphate; Animal Model; Automobile Driving; Calcium; Characteristics; Chemosensitization; Complex; Confocal Microscopy; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Data; Digestion; Electric Stimulation; Event; Exocytosis; Fluids and Secretions; Funding; Gland; Goals; Hydration status; Imaging Techniques; Inositol; Ion Channel; Lead; Liquid substance; Lubrication; Major salivary gland structure; Mechanics; Mediating; Mediator of activation protein; Microscopy; Molecular; Muscarinic Acetylcholine Receptor; Muscarinics; Nutrient; Optics; Oral cavity; Oral health; Oral mucous membrane structure; P2X-receptor; Parotid Gland; Pathway interactions; Pharmacology; Physiological; Physiology; Preparation; Process; Production; Property; Protein Secretion; Proteins; Purinoceptor; Quality of life; Receptor Activation; Regulation; Research Design; Saliva; Salivary; Salivary Glands; Series; Signal Transduction; Slice; Techniques; Therapeutic; Therapeutic Intervention; Tissues; Transgenic Animals; Upper digestive tract structure; Xerostomia; antimicrobial; base; design; digital imaging; in vivo; neural stimulation; novel; receptor; research study; saliva secretion; salivary acinar cell; treatment strategy

DESCRIPTION (provided by applicant): A key event in the secretagogue stimulation of both the fluid and protein component of saliva is an increase in the cytosolic free calcium concentration [Ca2+].i This increase in [Ca2+]i has specific temporal and spatial characteristics which are important for appropriately activating effectors pivotal for the secretion of saliva. Acetylcholine and the majority of other secretagogues act in a metabotropic manner stimulating the production of inositol 1,4,5-trisphosphate (InsP3) and the release of intracellular Ca2+. In salivary acinar cells, Ca2+ signals can also be generated by an alternative, largely independent ionotropic process following adenosine triphosphate (ATP) activation of the P2X class of Ca2+ permeable ion channels. The latter mechanism would be predicted to result in Ca2+ signals and effector activation with distinct spatial and temporal characteristics. Using contempory optical techniques, such as digital imaging, total internal reflection microscopy and confocal microscopy combined with transgenic animal models and specific pharmacology we will expand on findings generated in isolated salivary gland acini to define Ca2+ signaling events stimulated through both metabotropic and in particular through the P2X4 purinergic receptor (P2X4R) in an organotypic parotid gland slice preparation (aim 1). Ca2+ signals as a result of P2X4R activation are profoundly enhanced following protein kinase A (PKA) activation. Since fluid secretion is also enhanced when PKA is activated this may be the physiologically relevant situation. In specific aim 2 we propose to define the molecular mechanism underlying this event. In specific aim 3 a primary goal will also be to assess whether ionotropic purinergic signaling through P2X4 receptors (P2X4R), either alone, or following specific pharmacological manipulation is an effective activator of the fluid and exocytotic secretion mechanism. These studies are designed to advance our understanding of the complex series of regulated molecular events which result in fluid secretion and may ultimately lead to the design of therapeutic strategies for the treatment of xerostomia based on exploiting the physiology of remaining functional acinar tissue. Saliva is vital for oral health. It is essential for the hydration of the oral mucosa; it provides lubrication, begins nutrient digestion and imparts antimicrobial and mechanical protection for the mouth and upper gastrointestinal tract. Reduced flow of saliva (xerostomia) greatly impacts the quality of life of sufferers. A key event in the secretagogue stimulation of both the fluid and protein component of saliva is an increase in the cytosolic free calcium concentration [Ca2+].i These studies are designed to advance our understanding of the complex series of regulated molecular events which result in the increase in [Ca2+]i and hence fluid secretion. Ultimately these data are designed to lead to the design of therapeutic strategies for the treatment of xerostomia based on exploiting the physiology of remaining functional acinar tissue.

描述（由申请人提供）：唾液的液体和蛋白质成分的促进刺激的关键事件是胞质游离钙浓度的增加[Ca2+]。I[Ca2+] i的这种增加具有特定的时间和空间特性，对于适当激活效应的效应子的特定时间和空间特征很重要。乙酰胆碱和大多数其他促分子的作用，以代谢性方式刺激肌醇1,4,5-三磷酸（INSP3）的产生和细胞内Ca2+的释放。在唾液腺泡细胞中，在三磷酸腺苷（ATP）激活Ca2+渗透性离子通道的腺苷（ATP）激活后，CA2+信号也可以通过替代的，很大程度上独立的离子型过程产生。后一种机制将被预测会导致Ca2+信号和效应子激活，并具有不同的空间和时间特征。使用当代光学技术，例如数字成像，总内部反射显微镜和共斑显微镜结合了转基因动物模型和特定的药理学，我们将扩展基于在孤立的唾液腺acini中产生的发现，以定义Ca2+信号事件，通过p2x4 parot parot parot parot parot sletor（p2x4 parot）刺激，以定义CA2+信号事件准备（目标1）。蛋白激酶A（PKA）激活后，由于P2X4R激活而导致的Ca2+信号得到了深刻的增强。由于当激活PKA时，流体分泌也会增强，这可能是生理上相关的情况。在特定的目标2中，我们建议定义此事件的分子机制。在特定目标3中，主要目标还将是单独评估通过P2X4受体（P2X4R）的离子嘌呤能信号传导，还是遵循特定的药理学操纵是液体和胞外分泌机制的有效激活剂。这些研究旨在促进我们对复杂的一系列调节分子事件的理解，这些事件导致流体分泌，并最终可能导致设计基于利用剩余功能性腺泡组织的生理学的治疗静脉病毒的治疗策略。唾液对口腔健康至关重要。这对于口服粘膜的水合至关重要。它提供润滑，开始营养消化，并为口腔和上部胃肠道提供抗菌和机械保护。唾液流动减少（静态）极大地影响了患者的生活质量。唾液的液体和蛋白质成分的促刺激刺激的关键事件是胞质游离钙浓度的增加[Ca2+]。I这些研究旨在促进我们对一系列复杂的调节分子事件的理解，从而导致[CA2+] I和流体分泌增加。最终，这些数据旨在基于利用剩余功能性腺泡组织的生理学来实现治疗静态症的治疗策略。