title: Amino acid metabolism in pituitary adenomas.
abstract: Patients with pituitary adenomas were examined with positron emission tomography with the administration of 11C-labelled methionine. In a few patients comparative studies using the two stereo-isomers L- and D-methionine were also performed. The results showed a rapid distribution of D-methionine within the tumor tissue without signs of irreversible trapping of the tracer. L-methionine on the other hand was rapidly irreversibly trapped indicating the metabolic fate. It is concluded that 11C-L-methionine can be used to quantify amino acid metabolism in the tumors. The amino acid metabolism was evaluated in a group of adenomas before and after treatment with bromocriptine. The results indicate a marked reduction of the amino acid metabolism in prolactinomas amounting to 60%. These tumors at a later time responded with tumor shrinkage. Hormonally inactive tumors showed no effect of treatment.
authors.affiliation: Department of Neurorology, University Hospital, Uppsala, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Bergström
authors.forename: C
authors.initials: C
authors.lastname: Muhr
authors.forename: P O
authors.initials: PO
authors.lastname: Lundberg
authors.forename: K
authors.initials: K
authors.lastname: Bergström
authors.forename: H
authors.initials: H
authors.lastname: Lundqvist
authors.forename: B
authors.initials: B
authors.lastname: Långström
mesh_terms: D000236:Adenoma / Q000000981:diagnostic imaging / Q000378:metabolism*; D000596:Amino Acids / Q000378:metabolism*; D006801:Humans; D010911:Pituitary Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism*; D014055:Tomography, Emission-Computed
chemical_list: D000596:Amino Acids