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IBMX is one of the most potent and nonspecific inhibitors of cyclic nucleotide PDE (phosphodiesterases) with documented IC50 values for PDE1, 2, 3, 4, and 5 equaling 19, 50, 18, 13 and 32.
I 0022 (OTTO) 3-Isobutyl-1-methylxanthine, 99%+ Cas 28822-58-4 - used to regulate cyclic nucleotide mediated inhibition of 5-HT release from neuroendocrine cells by inhibiting phosphodiesterase.