Figure 5.

Measurement of recycled radioligand following incubation with 0.1 nM [¹²⁵I]-[Tyr¹¹]-SRIF for 15 min at 37°C and washed thoroughly with cold DMEM/HEPES/MES (pH 5.0) to remove surface bound radioactivity. Cells were then warmed to 37°C in fresh buffer containing 1 μM SRIF for various times. Buffer was collected and transferred to vials for counting, after which cells were solubilized and transferred to vials for estimation of residual internalized ligand. Data represent the mean of three experiments±s.e.mean in duplicate.