Confocal laser scanning microscopy of 3T3-L1 preadipocytes (A–K) or Swiss albino 3T3 fibroblasts (L and M) stained with Alexa Fluor® 488 labelled phalloidin. 3T3-L1 preadipocytes were incubated with the standard buffer for 30 min as controls (A), with 100 μM suramin for 7 min (B), 100 μM suramin for 2 min followed by 5 min with 10 μM ATP in the continued presence of suramin (C), 5 μM U-73122 for 30 min (D), 5 μM U-73122 for 25 min followed by 5 min with 10 μM ATP in the continued presence of U-73122 (E), 5 μM U-73343 for 30 min (F), 5 μM U-73343 for 25 min followed by 5 min with 10 μM ATP in the continued presence of U-73343 (G), 10 μM Y-27632 for 30 min (H and I) or 10 μM Y-27632 for 25 min followed by 5 min with 10 μM ATP in the continued presence of Y-27632 (J and K) before the staining procedure. Swiss albino 3T3 fibroblasts were incubated with standard buffer for 5 min at 37 °C as controls (L), or with 100 μM ATP in the standard buffer for 5 min at 37 °C (M) before the staining procedure. Results are representative of six experiments. Scale bar, 10 μm.