The radiotracers [¹¹C]COU and [¹¹C]PHXY are potential PET imaging agents for in vivo studies of monoamine oxidases (MAOs), as previously shown in rodent and primate brain. One-pot, automated methods for the radiosynthesis of [¹¹C]PHXY and [¹¹C]COU were developed to provide reliable and improved radiochemical yields. Although derived from the structure of the neurotoxin MPTP, COU did not exhibit in vivo neurotoxicity to dopaminergic nerve terminals in the mouse brain as assayed by losses of VMAT2 radioligand binding. PET imaging studies in rats demonstrated that both [¹¹C]COU and [¹¹C]PHXY exhibit retention in cardiac tissues that can be blocked by pretreatment with the MAO inhibitors deprenyl (MAO-B) and pargyline (MAO-A and -B). In addition to prior neuroimaging applications, [¹¹C]COU and [¹¹C]PHXY are thus also of interest for studies of MAO enzymatic activity and imaging of sympathetic nerve density in heart.

中文翻译：

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[11C]COU 和 [11C]PHXY 的改进合成、神经毒性评估以及啮齿动物心脏中 MAO 的成像

放射性示踪剂 [ ¹¹ C] COU 和 [ ¹¹ C] PHXY 是单胺氧化酶 (MAO) 体内研究的潜在 PET 显像剂，如先前在啮齿动物和灵长类动物大脑中所示。开发了用于[ ¹¹ C]PHXY 和[ ¹¹ C] COU 放射合成的一锅自动化方法，以提供可靠和改进的放射化学产率。尽管源自神经毒素 MPTP 的结构，但通过 VMAT2 放射性配体结合的丧失进行测定，COU 并未对小鼠大脑中的多巴胺能神经末梢表现出体内神经毒性。大鼠 PET 成像研究表明 [ ¹¹ C] COU 和 [ ¹¹C]PHXY 在心脏组织中表现出保留，可以通过用 MAO 抑制剂 deprenyl (MAO-B) 和 pargyline (MAO-A 和 -B) 进行预处理来阻断。除了先前的神经成像应用之外，[ ¹¹ C]COU 和 [ ¹¹ C]PHXY 也因此对 MAO 酶活性的研究和心脏交感神经密度的成像感兴趣。