CENTRAL RESPIRATORY CHEMORECEPTION IN AMPHIBIANS

两栖动物的中枢呼吸化学感受器

• 批准号: 7336120
• 负责人: MATTHEW J GDOVIN
• 金额: $ 12.03万
• 依托单位: UNIVERSITY OF TEXAS SAN ANTONIO
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2007-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7336120
• 关键词: CENTRAL; RESPIRATORY; CHEMORECEPTION; AMPHIBIANS

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. A. Specific AimsThe specific aims in the application have not changed. Experiments have been conducted as described in Specific Aim 1, specifically; we have collected intracellular pH ratios using the fluorescent dye BCECF in the in vitro tadpole brainstem preparation. B. Studies and Results We have performed experiments as described in Aim 1 to investigate intracellular pH (pHi) in the tadpole brainstem. We have recorded pHi in cell in both known chemoreceptive regions and non-chemosensitive regions of the tadpole medulla. We are currently collecting data during hypercapnic acidosis, and plan to soon collect data during the ammonium chloride prepulse and isohydric hypercapnia. In addition, we recently completed a study that demonstrated that the pH sensitive dye, BCECF, does not alter the spontaneous respiratory rhythm or the respiratory response to central chemoreceptor stimulation in vitro. This study involved calculating the percentage of cells that were loaded with BCECF following various incubation paradigms, recording whole nerve respiratory activities prior to and after dye incubation, and our ability to optically record pHi during hypercapnic acidosis. These data are currently being incorporated into a peer review research manuscript to be submitted during the current RCMI budget year. Gdovin, M.J., Costanzo, M.C., Ortiz, B.J., Zamora, D.A., and Jackson, V.V. ¿Optical recordings of intracellular pH and spontaneously respiratory rhythmicity in the in vitro tadpole brainstem preparation¿ Respiration Physiology and Neurobiology. We experienced technical difficulties with our fluorescence imaging system; specifically the computer that we use to capture, collect, and analyze data stopped working. We were told by Universal Imaging technical support, the support staff for the data acquisition software we use, that we needed to upgrade to a newer computer with more available hard drive space. While we temporarily fixed the problem, we expect to receive a quote from them soon and have funds to purchase this newer system. C. Significance We have successfully recorded respiratory motor nerve activity in the BCECF dye loaded brainstem of the tadpole, Rana catesbeiana. A very significant finding of this study is that the presence of the dye does not alter the spontaneous respiratory motor output or the respiratory response to central CO2 chemoreceptor stimulation. More importantly, we can record optical data of intracellular pH in vitro. As stated in the original grant proposal, we will soon be the first to report that the changes in pHi are indeed responsible for changes in respiratory motor output in a vertebrate model.D. PlansOur proposed research plan for year 2 is consistent with those described in the original grant application. Specifically, we will continue performing experiments described in Aim 1. In addition, we will begin to conduct experiments using bath applied agents to determine the roles of the Na+/H+ and Cl- dependent HCO3- exchangers in the regulation of intracellular pH, as described in Aim 2. In addition to the above progress, I also mentored Debora A. Zamora, a third year Ph.D. student in my lab, pertaining to grant writing. She submitted an F31 grant proposal in the Spring of 2005 pertaining to her doctoral research.

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。所列机构为中心机构，不一定为研究者机构。A.具体目标申请中的具体目标没有改变。具体而言，已按照具体目标1中所述进行了实验;我们在体外蝌蚪脑干制备中使用荧光染料BCECF收集了细胞内pH值比。 B。研究和结果我们进行了如目的1所述的实验，以研究蝌蚪脑干中的细胞内pH（pHi）。我们已经记录了细胞中的pHi在已知的化学感受性区域和非化学敏感区域的蝌蚪髓质。我们目前正在收集高碳酸血症期间的数据，并计划很快收集氯化铵前脉冲和等氢高碳酸血症期间的数据。此外，我们最近完成的一项研究表明，pH敏感染料，BCECF，不改变自主呼吸节律或呼吸反应的中央化学感受器刺激体外。这项研究涉及计算细胞的百分比，加载BCECF以下各种孵育范例，记录整个神经呼吸活动之前和之后的染料孵育，和我们的能力，光学记录pHi高碳酸酸中毒。目前正在将这些数据纳入将在本区域协调员倡议预算年度提交的同行审议研究手稿。Gdovin，M.J.，Costanzo，M.C.，Ortiz，B.J.，萨莫拉检察官和杰克逊，V. V.？光学记录细胞内pH值和自发呼吸节律在体外蝌蚪脑干制备<$呼吸生理学和神经生物学。 我们的荧光成像系统遇到了技术困难;特别是我们用来捕获、收集和分析数据的计算机停止工作。Universal Imaging技术支持部门（我们使用的数据采集软件的支持人员）告诉我们，我们需要升级到一台具有更多可用硬盘空间的更新计算机。虽然我们暂时修复了这个问题，但我们希望很快收到他们的报价，并有资金购买这个新系统。 C.我们成功地记录了呼吸运动神经活动的BCECF染料负载的蝌蚪，牛蛙脑干。 本研究的一个非常重要的发现是，染料的存在不会改变自发呼吸运动输出或对中枢CO2化学感受器刺激的呼吸反应。 更重要的是，我们可以在体外记录细胞内pH的光学数据。正如在最初的拨款建议中所述，我们很快将成为第一个报告pHi的变化确实是脊椎动物模型中呼吸运动输出变化的原因。计划我们提出的第二年的研究计划与原始拨款申请中描述的一致。具体而言，我们将继续进行目标1中描述的实验。 此外，我们将开始使用浴用试剂进行实验，以确定Na+/H+和Cl-依赖性HCO 3-交换剂在细胞内pH调节中的作用，如目标2所述。除了以上的进步，我还辅导了Debora A。萨莫拉博士三年级学生在我的实验室，有关赠款写作。她在2005年春季提交了一份关于她的博士研究的F31赠款提案。