Figure 3 PGE1 inhibits endocytosis in a PTX-insensitive manner. PGE1 inhibits endocytosis in a PTX-insensitive manner. The signaling pathways in the hormonally mediated inhibition of endocytosis were investigated in control and PTX-pretreated cells. (A) Endocytosis recorded in control and PTX-pretreated cells in the absence and presence of PGE1. (B) Summary of the endocytotic actions studied under the various test conditions (as labeled), in the early endocytosis (left panel) and late endocytosis (right panel) phases. The early and late phases of endocytosis are indicated as white and gray, respectively. Data were analyzed from 17 to 25 cells for each experimental condition. The control data and the protocols are the same as those reported in Fig. 2. *P < 0.05, **P < 0.01, #NS. Ying Zhao et al. J Endocrinol 2016;229:287-294 © 2016 Society for Endocrinology