Positron emission tomographic measurement of blood‐to‐brain and blood‐to‐tumor transport of 82Rb: The effect of dexamethasone and whole‐brain radiation therapy
Positron emission tomographic measurement of blood‐to‐brain and blood‐to‐tumor transport of 82Rb: The effect of dexamethasone and whole‐brain radiation therapy
复制标题
82Rb 的血液至大脑和血液至肿瘤转运的正电子发射断层扫描测量：地塞米松和全脑放射治疗的效果
作者：
J. O. Jarden;V. Dhawan;Alexander Poltorak;J. Posner;D. Rottenberg
在原发性或转移性脑肿瘤患者中，使用动态正电子发射断层扫描测定了铷82的单向血液-脑和血液-肿瘤转运速率常数。区域内流速率常数（K1）和血浆水体积（Vp）估计的时间过程中的血液和脑放射性后，弹丸注射示踪剂。8名患者在使用药理剂量的地塞米松治疗前和治疗后24至72小时进行了研究，另外6名转移性脑肿瘤患者在200至600 rad全脑放射治疗前和治疗后60至90分钟内进行了研究。类固醇治疗与肿瘤K1降低9 - 48%和肿瘤Vp平均降低21%相关。在对照脑区中未观察到K1或Vp的一致变化。在接受全脑放疗的患者中，肿瘤K1和Vp没有增加，所有患者在研究时都服用地塞米松。这些数据表明，皮质类固醇降低了肿瘤毛细血管对亲水性小分子（包括一些化疗药物）的渗透性，类固醇预处理可预防颅内照射后肿瘤毛细血管渗透性的急性和潜在危险性增加。
Unidirectional blood‐to‐brain and blood‐to‐tumor transport rate constants for rubidium 82 were determined using dynamic positron emission tomography in patients with primary or metastatic brain tumors. Regional influx rate constants (K1) and plasma water volume (Vp) were estimated from the time course of blood and brain radioactivity following a bolus injection of tracer. Eight patients were studied before and 24 to 72 hours after treatment using pharmacological doses of dexamethasone, and 6 additional patients with metastatic brain tumors were studied before and within 60 to 90 minutes after 200‐ to 600‐rad whole‐brain radiation therapy. Steroid treatment was associated with a 9 to 48% decrease in tumor K1 and a 21% mean decrease in tumor Vp. No consistent changes in K1 or Vp were observed in control brain regions. Tumor K1 and Vp did not increase in patients undergoing whole‐brain radiation therapy, all of whom were taking dexamethasone at the time of study. These data suggest that corticosteroids decrease the permeability of tumor capillaries to small hydrophilic molecules (including those of some chemotherapeutic agents) and that steroid pretreatment prevents acute, and potentially dangerous, increases in tumor capillary permeability following cranial irradiation.
类固醇抑制大鼠脑中分离的毛细血管对钾的吸收。
影响因子：
5.8
作者：
Chaplin,ER;Free,RG;Goldstein,GW
通讯作者：
Goldstein,GW
通过定量计算机断层扫描评估犬脑中的辐射效应。
影响因子：
19.7
作者：
Fike,JR;Cann,CE;Davis,RL;Phillips,TL
通讯作者：
Phillips,TL