The normal pituitary examined with positron emission tomography and (methyl-11C)-L-methionine and (methyl-11C)-D-methionine

✍ Scribed by M. Bergström; C. Muhr; K. Ericson; H. Lundqvist; A. Lilja; L. Eriksson; G. Blomquist; B. Långström; P. Johnström

• Publisher: Springer
• Year: 1987
• Tongue: English
• Weight: 439 KB
• Volume: 29
• Category: Article
• ISSN: 0028-3940
• DOI: 10.1007/bf00451757

✦ Synopsis

Four patients with radiologically normal pituitary gland were examined with positron emission tomography after the administration of (meth-ylJ1C)-L-methionine. On a following day the examination was repeated with (methyl-lOC)-D-methionine. The accumulation rate of L-methionine in the pituitary was measured, giving a value that was about twice that of normal brain tissue. The accumulation rate of D-methionine in the pituitary was almost a factor of 10 lower than that of L-methionine. In the normal brain tissue that ratio was 2.3. The study dearly indicates that the methionine uptake in the pituitary is stereospecific, uC-D-methionine is freely distributed in the tissue without entrapment, whereas 11C-L-methionine is irreversibly bound. It is concluded that PET with 11C-L-methionine can be used to study amino acid utilization in the pituitary.