Jarden J O
Neurologisk afdeling N, Bispebjerg Hospital, København.
Ugeskr Laeger. 1996 Jul 8;158(28):4086-90.
The effects of glucocorticoids (GC) on the blood-to-tumour barrier transport (BTT) and tissue blood volume (Vb) and aspects of brain tumour acid/base balance were studied in patients with brain tumours using positron emission tomography (PET). BTT was assessed by 82Rb/PET and quantitated as K1 (unidirectional transport constant), tissue blood volume was also measured by 82Rb/PET. The parameters were evaluated following start of GC. The pH was assessed with 11C-DMO/PET as a single measurement in patients receiving GC. GC treatment reduced the tumour K1 20% to 30%, within 6 to 24 hours following start of treatment. Brain tumours were in the alkalotic range compared to normal brain. The studies have helped to explain GC's antioedema effect and mechanisms behind the observed tumor alkalosis. The 82Rb/PET model seems useful for quantitative measurements of such parameters as pharmacological blood-tumour barrier opening, allowing continuous assessment of the potential for tumour chemotherapeutic uptake, thereby improving anti-cancer chemotherapy.
利用正电子发射断层扫描（PET）技术，在脑肿瘤患者中研究了糖皮质激素（GC）对血脑屏障转运（BTT）、组织血容量（Vb）以及脑肿瘤酸碱平衡方面的影响。通过82Rb/PET评估BTT，并将其定量为K1（单向转运常数），组织血容量也通过82Rb/PET进行测量。在开始使用GC后对这些参数进行评估。在接受GC治疗的患者中，使用11C-DMO/PET作为单一测量来评估pH值。GC治疗在开始治疗后的6至24小时内使肿瘤K1降低了20%至30%。与正常脑组织相比，脑肿瘤处于碱中毒范围。这些研究有助于解释GC的抗水肿作用以及观察到的肿瘤碱中毒背后的机制。82Rb/PET模型似乎可用于定量测量诸如药物性血脑屏障开放等参数，从而能够持续评估肿瘤化疗摄取的潜力，进而改善抗癌化疗效果。
