PERINATAL HYPOXIA: ADRENOCORTICAL-METABOLIC ADAPTATIONS

围产期缺氧：肾上腺皮质代谢适应

• 批准号: 6580136
• 负责人: HERSHEL RAFF
• 金额: $ 21.21万
• 依托单位: MEDICAL COLLEGE OF WISCONSIN
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-01-01 至 2006-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6580136
• 关键词: adrenocorticotropic hormone; arginine vasopressin; corticosteroid receptors; corticosterone; corticotropin releasing factor; embryo /fetus hypoxia; environmental adaptation; enzyme activity; glucocorticoids; hormone regulation /control mechanism; hormone therapy; hyperlipidemia; hypothalamic pituitary adrenal axis; hypoxia neonatorum; laboratory rat; lipid metabolism; metabolomics; mineralocorticoids; northern blottings; perinatal; polymerase chain reaction; proopiomelanocortin; receptor expression; steroid biosynthesis; stress

DESCRIPTION (provided by applicant): Hypoxia during the perinatal period and during early infancy is a significant cause of mortality and morbidity. Adrenocortical hormones are a vital component of the adaptation to hypoxic stress. Furthermore, neonatal hypoxic hyperlipidemia is a significant clinical entity, and changes in specific lipid metabolites alter adrenal function. The long-term objective of this proposal is to characterize the short and long-term consequences of perinatal hypoxia on the control of the hypothalamic-pituitary-adrenal (HPA) system and lipid metabolism in the rat. Specific Aims 1 and 2 will evaluate the effect of neonatal hypoxia on the control of the hypothalamic-pituitary-adrenal axis by evaluating intracellular and systemic controllers of steroidogenesis, the timing and mechanisms of the stress-hyporesponsive period (SHRP), and the negative feedback control of CRH and POMC expression and ACTH release. Specific Aim 3 will characterize the long-term sequellae of perinatal hypoxia by evaluating subsequent HPA responses to stimuli in the adult rat. Specific Aim 4 will more fully characterize neonatal hypoxic hyperlipidemia by analyzing the interaction of neonatal hypoxia and glucocorticoid therapy, and by performing metabolomic analysis. Neonatal hypoxia from birth is accomplished by exposing newborn rats (with their lactating dams) to a hypoxic environment. Perinatal hypoxia is accomplished by exposing late-gestational pregnant rats to hypoxia and allowing them to deliver in a hypoxic environment. Physiological, biochemical and molecular assessment of adrenocortical function is performed by ACTH injection in vivo, using dispersed cells, evaluating StAR and PBR expression, and measuring CBG and glucocorticoid clearance. Hypothalamic-pituitary function is assessed by measuring stress- and CRH-induced ACTH release, by evaluating feedback sensitivity, and by analyzing pituitary, hypothalamic, and hippocampal function and pertinent receptor/hormone expression. Metabolic function is assessed by analysis of hepatic enzyme activity, as well as complete metabolomic analysis of serum and hepatic lipids. Characterization of the hypothalamic-pituitary-adrenal and metabolic adaptations to perinatal hypoxia can lead to new diagnostic approaches and therapies to minimize morbidity and mortality.

描述（由申请人提供）：围产期和婴儿早期缺氧是死亡和发病的重要原因。肾上腺皮质激素是适应缺氧应激的重要组成部分。此外，新生儿缺氧性高脂血症是一个重要的临床实体，特定脂质代谢物的变化改变肾上腺功能。本建议的长期目标是表征围产期缺氧对大鼠下丘脑-垂体-肾上腺（HPA）系统和脂质代谢控制的短期和长期后果。具体目标1和2将通过评价类固醇生成的细胞内和全身控制器、应激低反应期（SHRP）的时间和机制以及CRH和POMC表达和ACTH释放的负反馈控制，评价新生儿缺氧对下丘脑-垂体-肾上腺轴控制的影响。具体目标3将通过评估成年大鼠对刺激的后续HPA反应来表征围产期缺氧的长期后遗症。具体目标4将通过分析新生儿缺氧和糖皮质激素治疗的相互作用以及进行代谢组学分析，更全面地表征新生儿缺氧性高脂血症。通过将新生大鼠（及其哺乳期母鼠）暴露于缺氧环境，实现出生后的新生儿缺氧。围产期缺氧是通过将妊娠晚期的大鼠暴露于缺氧环境中并允许它们在缺氧环境中分娩来实现的。肾上腺皮质功能的生理学、生物化学和分子学评估通过体内ACTH注射进行，使用分散的细胞，评估星星和PBR表达，并测量CBG和糖皮质激素清除率。通过测量应激和CRH诱导的ACTH释放，通过评价反馈敏感性，以及通过分析垂体、下丘脑和海马功能和相关受体/激素表达来评估下丘脑-垂体功能。通过肝酶活性分析以及血清和肝脏脂质的完全代谢组学分析评估代谢功能。下丘脑-垂体-肾上腺和围产期缺氧代谢适应的特征可以带来新的诊断方法和疗法，以最大限度地减少发病率和死亡率。