Radiolabelled D2 agonists as prolactinoma imaging agents: Progress report for period February 1, 1988--January 31, 1989

Targeted studies completed include the evaluation of tritiated N-0437, evaluation of 35S-cysteamine, evaluation of 18F-FDG and initiation of synthetic efforts towards the synthesis of iodinated N-0437 and pergolide analogs. The direction of the project has been changed due to several factors which include the decided lack of favorable experimental results, the excellence of results using muscarinic receptor ligands in pituitary, brain and heart and the contention of the DOE review panel that the original grant proposal was based on flawed assumptions together with their perceived lack of importance to pituitary imaging. In the final year of this grant, three studies will be completed. The first study is the continuation of synthetic efforts to prepare iodinated N-0437 and pergolide analogs for possible use as brain imaging agents. The second study is directed towards completion of biochemical evaluation of various muscarinic receptor analogs for heart, brain and (possible) pituitary imaging. The third study is to probe the use of quaternized D2 receptor ligands for imaging peripheral dopaminergic receptors (including the pituitary). 14 refs., 1 fig., 7 tabs