Distribution of radiolabeled ELLs and PBLs after intravenous injection. The total radioactivity recovered in each sampled tissue was divided by the weight of the sample (in grams), and then the percentage of injected radioactivity recovered per gram of tissue was calculated. (▨) ELLs; (▪) PBLs. Mean of 4 animals ± SEM. *PBL localization significantly different from ELLs, P < .05. Paired t-test.