Ibudilast

Forskolin (Sigma, U.K.) was diluted to a stock of 100 mM in DMSO (Sigma, U.K.). All PDE inhibitors were initially supplied by IOTA Pharmaceuticals. The names of the compounds were only known to IOTA Pharmaceuticals and initial experiments (Figures 2 and3) were performed blind. Upon data analysis, IOTA Pharmaceuticals decoded the compounds to enable subsequent characterisation. Trequinsin, PF-2545920, vinpocetine, sildenafil, rolipram, cilostamide, caffeine, SQ22536, EHNA, amrinone, zaprinast, TC3.6, ibudilast, milrinone, BAY 73-6691, BRL-50481, piclamilast, IBMX, roflumilast, tadalafil, PF-04449613 (all purchased from Sigma, UK), BC 11-38, and PF 04671536 (both obtained from Tocris, UK) were dissolved in DMSO to stock concentrations of either 100 mM or 10 mM. Guanylyl cyclase activators BAY 41-8543 and YC-1 were purchased from Tocris and diluted to a stock of 100 mM in DMSO.
Epac inhibitors ESI-09, HJC0350, and CE3F4 (all purchased from Sigma, UK) were diluted to 10 mM stocks in DMSO. PKA and PKG inhibitors, KT5720 and KT5823, respectively (all obtained from Cambridge Insight Biotechnology, UK) were diluted to stocks of 10 mM and 1 mM, respectively.