Mechanical strain-induced TSP-1 expression is mediated by P2 receptors and protein kinase signaling. Astrocytes grown on deformable silicone membranes were treated with the P2 receptor antagonist PPADS (50 μM; 15 min) or the p38/MAPK/Akt inhibitor SB202190 (10 μM; 30 min) before being subjected to mechanical strain (50-ms, 7.5-mm membrane displacement). After 6 h, cell lysates were collected. Immunoblottings and quantitation of data as bar graphs show that PPADS (A) and SB202190 (B) significantly blocked mechanical strain-induced expression of TSP-1 (∗, P < 0.05; ∗∗, P < 0.01; n = 3), indicating involvement of P2 receptor and protein kinase signaling in the expression of TSP-1 induced by trauma.