Figure 5.

Peroxisome proliferator–activated receptor gamma (PPARγ) negatively regulates proline-rich tyrosine kinase 2 (Pyk2) in human pulmonary artery smooth muscle cells (HPASMCs). A, HPASMCs were transfected with control small interfering RNA (si-Con) or PPARγ small interfering RNA (si-PPARγ) for 72 hours. Cell lysates were analyzed for Pyk2 activation with an anti-phospho-(Tyr402)-Pyk2 antibody. Total Pyk2 levels were used for normalization. PPARγ levels were determined by Western blotting to verify depletion. n = 6. ^**P < 0.01 versus si-Con. B, HPASMCs were transduced with adenovirus containing control vector (Ad-Con) or adenovirus containing PPARγ to a multiplicity of infection of 28. Cell lysates were immunoblotted for phospho-Pyk2 and total Pyk2. PPARγ levels were determined to verify its overexpression (PPARγ-OE). A lower exposure was taken to highlight the sharpness of the overexpressed PPARγ protein. n = 3. ^*P < 0.05 versus Ad-Con. In both panels, each bar represents the ratio phospho-Pyk2/total Pyk2, expressed as fold change versus control. GAPDH: glyceraldehyde 3-phosphate dehydrogenase.