I remember reading an article some time ago about storage of levodopa in muscle tissue of pigs. Of course I can't find it now, but I did find this one on rats. It appears that levodopa is not rapidly decarboxylated in muscle so has a longer half life than in blood.
The effect of carbidopa on plasma and muscle levels of L-dopa, dopamine, and their metabolites following L-dopa administration to rats. - PubMed - NCBI