Mu Opioid Receptor Regulation in Neonatal Brainstem

新生儿脑干中的 Mu 阿片受体调节

• 批准号: 7035880
• 负责人: GEORGE D OLSEN
• 金额: $ 25.8万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-12-15 至 2008-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7035880
• 关键词: CHO cells; G protein; autoradiography; brain stem; disease /disorder model; drug abuse; drug withdrawal; embryo /fetus toxicology; guanosine triphosphate; guinea pigs; heroin; hyperpnea; immunocytochemistry; lung development; methadone; nucleic acid purification; opioid receptor; placental transfer; polymerase chain reaction; protein structure function; receptor binding; receptor coupling; receptor expression; respiratory disorder; transfection; transfection /expression vector

DESCRIPTION (provided by applicant): The long-term goal of the proposed research is to understand mechanisms by which chronic in utero morphine and methadone exposure affect regulation and function of mu opioid receptors (MOR) in respiratory control areas of newborn brainstem. Respiratory depression is induced by endogenous opioid peptides and exogenous opioids that activate MOR. A critical brainstem site for these effects is the nucleus tractus solitarius (NTS), which integrates sensory signals and drives respiratory muscles. Profound disturbance of neonatal breathing is a well-documented consequence of maternal opioid abuse. These neonates exhibit withdrawal hyperventilation and an increased incidence of sudden infant death syndrome (SIDS). The proposed studies are essential for understanding normal respiratory development, drug-induced changes, and effective treatment of pregnant heroin addicts and methadone maintained patients. The exact role of NTS MOR in neonatal congenital narcotic dependence and these respiratory disturbances is unknown. For anatomical, physiological, and pharmacological reasons, the guinea pig is a superb model for study of maternal opioid abuse. Guinea pig kappa opioid receptor has been cloned, but only partial sequences of MOR and delta opioid receptors have been available. However, our laboratory has recently determined the complete guinea pig MOR cDNA sequence. Availability of this sequence will enable us to define for the first time guinea pig MOR pharmacology, and systematically compare it to human and mouse MOR. Research is guided by four hypotheses: 1) guinea pig MOR is functionally similar to human MOR with respect to mu agonist efficacy, binding kinetics, and activation of G-protein, but different from murine MOR; 2) methadone induces respiratory depression and is equipotent to, but of longer duration than morphine in the neonatal guinea pig; 3) chronic in utero morphine and methadone exposure results in increased functional MOR on the cell surface, but decreases the coupling efficiency of MOR with G-proteins in the NTS; 4) chronic in utero morphine and methadone exposure up-regulates MOR mRNA in the NTS. Hypotheses are explored through four specific aims: 1) to compare mu agonist selectivity and potency, and development of cellular tolerance for guinea pig, human and murine MOR each expressed in stably transfected CHO cells; 2) to prove that the respiratory effects of methadone are similar to morphine in the neonatal guinea pig; 3) to study the effects of morphine and methadone on guinea pig MOR in NTS of brainstem sections from guinea pig neonates exposed in utero; and 4) to quantitate MOR mRNA in NTS from guinea pig neonates exposed to morphine and methadone in utero. These studies will provide developmental information on guinea pig NTS MOR following chronic in utero opioid exposure.

描述（由申请人提供）：拟议研究的长期目标是了解长期宫内吗啡和美沙酮暴露影响新生儿脑干呼吸控制区μ阿片受体（莫尔）调节和功能的机制。呼吸抑制由激活莫尔的内源性阿片肽和外源性阿片类物质诱导。这些效应的一个关键脑干部位是孤束核（NTS），它整合感觉信号并驱动呼吸肌。新生儿呼吸的严重障碍是一个有据可查的结果，母亲阿片类药物滥用。这些新生儿表现出戒断性过度通气和婴儿猝死综合征（SIDS）的发病率增加。拟议的研究是必不可少的了解正常的呼吸系统发育，药物引起的变化，并有效地治疗怀孕的海洛因成瘾者和美沙酮维持患者。NTS莫尔在新生儿先天性麻醉药依赖和这些呼吸障碍中的确切作用尚不清楚。由于解剖学、生理学和药理学原因，豚鼠是研究母体阿片类药物滥用的极好模型。豚鼠κ阿片受体已被克隆，但只有部分序列的莫尔和δ阿片受体已获得。然而，我们的实验室最近确定了完整的豚鼠莫尔cDNA序列。该序列的可用性将使我们能够首次定义豚鼠莫尔药理学，并将其与人和小鼠莫尔进行系统比较。研究由四个假设指导：1）豚鼠莫尔在μ激动剂功效、结合动力学和G蛋白活化方面与人莫尔功能相似，但与鼠莫尔不同; 2）美沙酮诱导呼吸抑制，并且在新生豚鼠中与吗啡等效，但持续时间更长;（3）宫内长期暴露吗啡和美沙酮可使孤束核细胞表面功能性莫尔增加，但降低了莫尔与G蛋白的偶联效率;（4）长期宫内吗啡和美沙酮暴露上调孤束核莫尔受体mRNA表达。通过四个具体目的探索假设：1）比较μ激动剂的选择性和效力，以及对各自在稳定转染的CHO细胞中表达的豚鼠、人和鼠莫尔的细胞耐受性的形成; 2）证明美沙酮在新生豚鼠中的呼吸作用与吗啡相似;（3）研究吗啡和美沙酮对宫内暴露的豚鼠新生儿脑干切片孤束核（NTS）莫尔的影响;（4）定量测定宫内暴露的豚鼠新生儿孤束核（NTS）莫尔mRNA。这些研究将提供关于豚鼠NTS莫尔在长期宫内阿片类药物暴露后的发育信息。

项目成果

Effects of chronic opioid exposure on guinea pig mu opioid receptor in Chinese hamster ovary cells: comparison with human and rat receptor.

慢性阿片类药物暴露对中国仓鼠卵巢细胞中豚鼠 ​​mu 阿片类受体的影响：与人和大鼠受体的比较。

• DOI: 10.1016/j.bcp.2007.02.001
• 发表时间: 2007
• 期刊: Biochemical pharmacology
• 影响因子: 5.8
• 作者: Wallisch,Michael;Nelson,ColeS;Mulvaney,JuliaM;Hernandez,HeatherS;Smith,SueAnn;Olsen,GeorgeD
• 通讯作者: Olsen,GeorgeD

Mu opioid receptor efficacy and potency of morphine-6-glucuronide in neonatal guinea pig brainstem membranes: comparison with transfected CHO cells.

Mu 阿片受体功效和吗啡-6-葡萄糖醛酸在新生豚鼠脑干膜中的效力：与转染的 CHO 细胞比较。

• DOI: 10.1016/s0361-9230(01)00427-0
• 发表时间: 2001
• 期刊: Brain research bulletin
• 影响因子: 3.8
• 作者: Gray,RE;Munks,MW;Haynes,RR;Olsen,GD
• 通讯作者: Olsen,GD

Chronic intermittent in utero exposure to morphine: effects on respiratory control in the neonatal guinea pig.

子宫内慢性间歇性接触吗啡：对新生豚鼠呼吸控制的影响。

• DOI: 10.1159/000244496
• 发表时间: 1997
• 期刊: Biology of the neonate
• 作者: Hunter,MA;Vangelisti,GR;Olsen,GD
• 通讯作者: Olsen,GD

Guinea pig mu opioid receptor: brainstem expression in the morphine-exposed neonate.

豚鼠 mu 阿片受体：吗啡暴露新生儿脑干的表达。

• DOI: 10.1016/j.ntt.2003.09.004
• 发表时间: 2004
• 期刊: Neurotoxicology and teratology
• 影响因子: 2.9
• 作者: Smith,SueAnn;Stupfel,JamesT;Ilias,NasreenA;Olsen,GeorgeD
• 通讯作者: Olsen,GeorgeD

Effects of morphine and cocaine on breathing control in neonatal animals: a minireview.

吗啡和可卡因对新生动物呼吸控制的影响：小型回顾。

• 发表时间: 1995
• 期刊: NIDA research monograph.
• 作者: Olsen,GD;Murphey,LJ
• 通讯作者: Murphey,LJ