Kinase regulation of VE-cadherin and VE-PTP association. (A) ERK1/2 activation is not required for VE-cadherin/VE-PTP dissociation. TNF-α–stimulated bEnd.5 cells were preincubated with the ERK1/2 inhibitor U0126 (or the negative control substance U0124) (both at 10 μM), followed by incubation with or without T cells and subsequent VE-PTP/VE-cadherin coimmunoprecipitation analysis. (B) Src inhibition does not prevent VE-cadherin/VE-PTP dissociation. The same process was done as in panel A, but cells were treated with the Src inhbitors PP2 (10 μM) or SU6566 (5 μM).