Use of micro-positron emission tomography with 18F-fallypride to measure the levels of dopamine receptor-D2 and 18F-FDG as molecular imaging tracer in the pituitary glands and prolactinomas of Fischer-344 rats

Abstract

OncoTargets and Therapy Dovepresssubmit your manuscript | www.dovepress.com Dovepress 2057O r i g i n a l r e s e a r c h open access to scientific and medical research Abstract: Dopamine receptor-D2 (DRD2) is the most important drug target in prolactinoma.The aim of this current study was to investigate the role of using micro-positron emission tomography (micro-PET) with 18 F-fallypride and 18 F-fluorodeoxyglucose ( 18 F-FDG) as molecular imaging tracer in the pituitary glands and prolactinomas of Fischer-344 (F344) rats and detect the difference of the levels of DRD2 in the pituitary glands and prolactinomas of F344 rat prolactinoma models. Female F344 rat prolactinoma models were established by subcutaneous administration of 15 mg 17β-estradiol for 8 weeks. The growth of tumors was monitored by the small-animal magnetic resonance imaging and micro-PET. A series of molecular biological experiments were also performed 4 and 6 weeks after pump implantation. The micro-PET molecular imaging with 18 F-fallypride revealed a decreased expression of DRD2 in F344 rat prolactinoma models, but the micro-PET molecular imaging with 18 F-FDG presented an increased uptake in the prolactinoma compared with the pituitary gland. A decreasing trend of levels of DRD2 in F344 rat prolactinoma models was also detected by molecular biological experiments. From this, we can conclude that micro-PET with 18 Ffallypride and 18 F-FDG can be used to assess tumorigenesis of the prolactinomas in vivo and molecular imaging detection of DRD2 level in prolactinoma may be an indication of treatment effect in the animal experiment.

18F-fallypride and 11C-methionine positron emission tomography/computed tomography for the study of prolactinomas and nonfunctioning pituitary adenomas: A case series

“…[ 12 13 14 ] As it is labeled with 18 F (half-life of 110 min), it can be synthesized in a center with an onsite cyclotron and then transported for use in distant clinics. Although a previous study described the use of 18 F-fallypride in animal models of prolactinomas,[ 15 ] there are no published papers on the use of this tracer in patients with prolactinomas and nonfunctioning adenomas.…”