Oxidative stress in regional cerebral blood flow alterations after cardiac arrest

描述（由申请人提供）：儿童心脏骤停仍然是死亡和发病的重要原因，因此是一个重要的公共卫生问题。在美国，估计每年有16，000名儿童死于心脏骤停。窒息是大多数儿童心脏骤停的原因。大多数幸存者都有严重的神经损伤。复苏后的脑血流（CBF）紊乱可能进一步导致心脏骤停后的神经病理损伤。活性氧和活性氮在调节CBF中起重要作用，并且在心脏骤停复苏期间和之后产生。CBF、脑代谢、氧化应激、硝化应激和这些因素的相互作用在儿科心脏骤停中仍有待确定，并且可能代表改善这种衰弱性疾病的结果的重要治疗靶点。该候选人最近开发了一种通过动脉自旋标记MRI对出生后17天大鼠的CBF进行系列和区域评估的方案，并发现窒息性心脏骤停后CBF的损伤持续时间依赖性。候选人将（i）确定CBF，脑代谢和神经病理损伤之间的关系，（ii）量化两次窒息心脏骤停（8.5分钟和12分钟）后一氧化氮，活性氧和其他活性氮的产生。候选人还将（iii）确定是否清除血管或实质中的ROS和RNS！隔室将防止病理性CBF改变并减少窒息性心脏骤停后的神经病理损伤。将通过动脉自旋标记MRI连续测量局部CBF。将采用放射自显影术测量葡萄糖的脑代谢率。将使用组织微传感器在体内连续测量一氧化氮，并使用电子顺磁共振光谱法在体外测量一氧化氮。氧化和亚硝化应激也将被量化：我们将通过ELISA和免疫荧光测量3-硝基酪氨酸，通过高液场色谱测量抗坏血酸，通过荧光测量还原型谷胱甘肽。候选人是匹兹堡儿童医院的儿科急诊医生。有必要培训儿科急诊临床医生-科学家，因为可能影响儿科心脏骤停后结果的干预措施最好应该在骤停现场或急诊科开始。这个指导职业发展奖将允许候选人追求复苏医学的独特和高度整合的指导计划。为了确保成功成为一名独立的临床医生-科学家，候选人组建了一个多学科和多机构咨询委员会，其中包括在1）复苏研究，2）血管生物学，3）氧化应激，4）MRI和5）儿科临床复苏指南制定和实施方面具有特殊专长的高级导师。

DESCRIPTION (provided by applicant): Pediatric cardiac arrest remains a significant cause of mortality and morbidity and thus it is an important public health problem. In the United States, it is estimated that 16,000 children die annually of cardiac arrest. Asphyxia is the cause of cardiac arrest in the majority of pediatric victims. Most survivors have severe neurological impairment. Cerebral blood flow (CBF) disturbances after resuscitation may further contribute to neuropathological damage after cardiac arrest. Reactive oxygen and nitrogen species play an important role in regulating CBF, and are generated during and after resuscitation from cardiac arrest. CBF, cerebral metabolism, oxidative stress, nitrative stress and the interaction of these factors remain to be defined in pediatric cardiac arrest, and may represent an important therapeutic target toward improving outcome of this debilitating condition. The candidate recently has developed a protocol for serial and regional assessment of CBF in developing postnatal day 17 rats via arterial spin label MRI and found insult duration dependency of CBF after asphyxial cardiac arrest. The candidate will (i) determine the relationship between CBF, cerebral metabolism and neuropathological damage and (ii) quantify production of nitric oxide, reactive oxygen species and other reactive nitrogen species after two durations of asphyxial cardiac arrest (8.5 min and 12 min). The candidate will also (iii) determine if scavenging ROS and RNS in either vascular or parenchyma! compartments will prevent pathological CBF alterations and reduce neuropathological damage after asphyxial cardiac arrest. Regional CBF will be measured serially via arterial spin label MRI. Cerebral metabolic rate for glucose will be measured with autoradiography. Nitric oxide will be measured in vivo serially with tissue minisensors and ex vivo with electron paramagnetic resonance spectroscopy. Oxidative and nitrosative stress will also be quantified: we will measure 3-nitrotyrosine by ELISA and immunofluorescence, ascorbic acid by high liquid field chromatography, and reduced glutathione by fluorescence. The candidate is a pediatric emergency physician at Children's Hospital of Pittsburgh. There is a need for training pediatric emergency clinician-scientists, as interventions likely to impact outcome after pediatric cardiac arrest should ideally be started at the arrest scene or in the Emergency Department. This Mentored Career Development Award will allow the candidate to pursue a unique and highly integrated mentored program in resuscitation medicine. To assure success in becoming an independent clinician-scientist, the candidate assembled a multidisciplinary and multi-institutional advisory committee that includes senior mentors with special expertise in 1) resuscitation research, 2) vascular biology, 3) oxidative stress, 4) MRI and 5) pediatric clinical resuscitation guidelines development and implementation.