Effect of Lead on Ion Transport in Fathead Gill

铅对黑头鱼鳃离子传输的影响

• 批准号: 7354874
• 负责人: ERIC G SPOKAS
• 金额: $ 1.41万
• 依托单位: RIDER UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-30 至 2007-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7354874
• 关键词: Osteichthyes; electrospray ionization mass spectrometry; environmental exposure; enzyme activity; fresh water environment; gills; glutathione; ion transport; isoproterenol; lead; lipid peroxides; peroxidation; phosphorylation; respiratory epithelium; respiratory function; sodium potassium exchanging ATPase; toxicant screening; unsaturated fatty acids

DESCRIPTION (provided by applicant): The objective of this proposal is to evaluate the effect of chronic lead exposure (water-borne divalent lead) on sodium, potassium ATP-ase (Na+K+-ATPase, sodium pump) activity in the gill of Pimephales promelas (fathead minnow) and how this enzymatic activity is affected by lead-induced peroxidation of gill lipids. Our working hypothesis is that lead affects Na+K+-ATPase by promoting formation of isoprostanes (iPs), prostaglandin-like fatty acid derivatives, within gill membranes by a free radical-mediated mechanism. Our initial studies, using isolated gill preparations, indicate that concentrations of lead near 1 ppm cause pronounced stimulation of Na+K+-ATPase activity. Priority will be given to gaining a more complete picture of the dose and time-dependence of this in vitro effect. Subsequently, we will evaluate the possible dependence of the stimulatory effect on protein phosphorylation. The in vivo influence of lead on gill Na+K+-ATPase activity will be examined in aquarium studies wherein adult fathead minnows are exposed to selected concentrations of lead (as lead nitrate) for up to 3 months. As part of this work, the tissue distribution of lead will be determined (e.g., gills, skin and muscle, viscera, skeleton) as well as the temporal relationships between accumulation of lead in the gill and sodium pump activity. Similar experiments will be carried out to follow the time course for the release of gill iPs in fish exposed to lead in the aquarium water. Gill lipids will be extracted, and analyzed by LC/MS-Electrospray, with structural confirmation with authentic and deuterated homologous standards. In some experiments iP release will be measured after adding lead to in vitro preparations (isolated gills and membrane fractions) from control fish. In both the in vivo and in vitro studies, we will determine the lead concentration of gill membrane fractions enriched in sodium pump activity. Data will be analyzed to determine if membrane lead levels correlate with Na+K+-ATPase activity and/or iP generation. Later in the project, we will evaluate the hypothesis that chronic lead exposure may result in a compensatory rise in levels of reduced glutathione (GSH) within the gill. Also, in the last year, renal proximal tubules will be isolated from rats administered lead in the drinking water. Suspensions of tubules will be incubated to assess iP biosynthesis, sodium pump activity, and GSH status. Results will be analyzed to determine if lead causes analogous iP-dependent changes in proximal nephron and gill epithelium.

描述（由申请方提供）：本提案的目的是评价慢性铅暴露（水性二价铅）对黑头呆鱼（黑头呆鱼）鳃中钠、钾ATP酶（Na+K+-ATP酶，钠泵）活性的影响，以及铅诱导的鳃脂质过氧化如何影响该酶活性。我们的工作假设是，铅影响Na+K+-ATP酶通过促进形成的异前列腺素（iPs），类前列腺素脂肪酸衍生物，鳃膜内的自由基介导的机制。我们的初步研究，使用离体鳃制剂，表明浓度接近1 ppm的铅导致Na+K+-ATP酶活性的显着刺激。将优先考虑更全面地了解这种体外效应的剂量和时间依赖性。随后，我们将评估刺激作用对蛋白质磷酸化的可能依赖性。铅对鳃Na+K+-ATP酶活性的体内影响将在水族馆研究中进行检查，其中成年黑头呆鱼暴露于选定浓度的铅（硝酸铅）长达3个月。作为这项工作的一部分，将确定铅的组织分布（例如，鳃、皮肤和肌肉、内脏、骨骼）以及铅在鳃中积累与钠泵活性之间的时间关系。将进行类似的实验，以跟踪暴露于水族馆水中铅的鱼的鳃iPs释放的时间过程。将提取鳃脂质，并通过LC/MS-电喷雾进行分析，使用真实和氘代同源标准品进行结构确认。在某些实验中，将铅加入对照鱼的体外制剂（分离的鳃和膜部分）后，测量iP释放。在体内和体外研究中，我们将确定富含钠泵活性的鳃膜组分的铅浓度。将分析数据以确定膜铅水平是否与Na+K+-ATP酶活性和/或iP生成相关。在该项目的稍后部分，我们将评估慢性铅暴露可能导致鳃内还原型谷胱甘肽（GSH）水平补偿性上升的假设。此外，在过去的一年中，肾近端小管将被分离出大鼠管理的饮用水中的铅。将孵育小管悬浮液以评估iP生物合成、钠泵活性和GSH状态。将分析结果以确定铅是否引起近端肾单位和鳃上皮细胞中类似的iP依赖性变化。

项目成果

Tissue lead concentration during chronic exposure of Pimephales promelas (fathead minnow) to lead nitrate in aquarium water.

Pimephales promelas（黑头米诺）长期暴露于水族馆水中的硝酸铅期间的组织铅浓度。

• DOI: 10.1021/es060811o
• 发表时间: 2006
• 期刊: Environmental science & technology
• 影响因子: 11.4
• 作者: Spokas,EricG;Spur,BerndW;Smith,Holly;Kemp,FrancisW;Bogden,JohnD
• 通讯作者: Bogden,JohnD

Rapid measurement of low levels of sodium, potassium-ATPase activity by ascorbic acid reduction without strong acid.

无需强酸即可通过抗坏血酸还原快速测量低水平的钠、钾-ATP 酶活性。

• DOI: 10.1006/abio.2001.5407
• 发表时间: 2001
• 期刊: Analytical biochemistry.
• 作者: Spokas,EG;Spur,BW
• 通讯作者: Spur,BW

Characterization of sodium, potassium, ATPase activity in the gills of Pimephales promelas (fathead minnow): influence of in vitro exposure to lead.

Pimephales promelas（黑头米诺）鳃中钠、钾、ATP 酶活性的表征：体外接触铅的影响。

• DOI: 10.1007/s00128-002-0074-x
• 发表时间: 2002
• 期刊: Bulletin of environmental contamination and toxicology
• 影响因子: 2.7
• 作者: Spokas,EG;Crivellone,MD;Kemp,F;Bogden,JD;Cohen,GM
• 通讯作者: Cohen,GM

Release of the lipid peroxidation marker 8-epi-prostaglandin F2 alpha from isolated gill pavement cells.

从分离的鳃铺层细胞中释放脂质过氧化标记物 8-表观前列腺素 F2 α。

• DOI: 10.1897/07-510.1
• 发表时间: 2008
• 期刊: Environmental toxicology and chemistry
• 影响因子: 4.1
• 作者: Spokas,EricG;Harshman,Scott;Cohen,GlennM;Jiang,Chen;Levine,JaimeM;Rodriguez,AnaR;Foglein,Jon;Spur,BerndW
• 通讯作者: Spur,BerndW