Figure 5 - COS-1 cells transfected with cDNA encoding the sst2A somatostatin (SRIF) receptor and incubated for 30 min with 20 nM fluo-SRIF at 37oC. The intracellular labeling pattern, seen here after wash-out of surface-bound ligand with hypertonic acid buffer, is similar to that observed with fluo-NT in NT-1-transfected COS-7 cells (see Figure 4). Small, intensely labeled endosome-like particles pervade the cytoplasm of the cells. n, Nucleus. Scale bar: 10 Ám.the cytoplasm but spare the nucleus (n). Scale bar: 10 Ám.