Figure 3.

PTPμ and ZA protein expression and barrier responsiveness to PTP inhibition in HMEC-1 cells. A: RT-PCR was used to detect PTPμ mRNA in HMEC-1 cells. The control DNA ladder is shown on the left and the negative control is on the right. B and C: Lysates of postconfluent HMEC-1 cells were resolved by SDS-PAGE, transferred to PVDF membrane, and immunoblotted for PTPμ (B), VE-cadherin, and α-, β-, γ-, and p120 catenins (C). C: The blot was stripped and reprobed for β-tubulin. Molecular weight markers in kd are indicated. D: Vertical bars represent mean (±SE) transendothelial ¹⁴C-BSA flux in pmol/hour immediately after 6 hours of exposure to increasing concentrations of vanadate or media alone. n indicates the number of monolayers studied. Mean (±SE) ¹⁴C-BSA flux across naked filters without EC monolayers is shown. *, Significantly increased compared to the simultaneous media control monolayers at P < 0.05.