Brain and brain tumor uptake of L-3-[123I]iodo-alpha-methyl tyrosine: competition with natural L-amino acids.

摘要: SPECT studies with L-3-(123I)iodo-alpha-methyl tyrosine (IMT) were carried out in 10 patients different types of brain tumors--first under fasting conditions (basal) and a week later during intravenous infusion mixture naturally-occurring L-amino acids (AA load). An uptake index (UI) was calculated by dividing tissue count rates the integral plasma rates. The UI decreased 45.6% {plus minus} 15.4% (n = 10, p less than 0.001) for normal 53.2% 14.1% gliomas 5, 0.01) AA load compared to basal conditions, while two meningiomas metastasis showed only minor decrease (23.9 5.7%, n.s.). Two pituitary adenomas could not be delineated on scans. These data indicate that IMT competes transport into gliomas. Transport characteristics tumors nonglial origin appear from those For both tumors, it is advisable perform IMT-SPECT conditions.