Radioiodination and bioevaluation of rolipram as a tracer for brain imaging: In silico study, molecular modeling and gamma scintigraphy.

Brain imaging is considered one of the most fruitful applications of radioisotope scanning. Rolipram, a selective phospodiesterase-4 inhibitor, has been labeled using [125 I] with chloramine-T (Ch-T) as an oxidizing agent. Factors, such as the amount of substrate, pH, the amount of oxidizing agent, temperature, and the reaction time, have been systematically studied to optimize the iodination process. In addition, bio-distribution studies have indicated that the brain uptake of [125 I]iodorolipram is 7.6 ± 0.33 injected dose/g organ at 10 minutes post-injection, which cleared from the brain with time until it reaches 1.30 ± 0.17% at 1 hour post-injection. Therefore, iodorolipram could be considered as a potential, new selective radiotracer for brain imaging.