Possible Interaction: Berberine and Methylene Blue

“Pretreatment with N(G)-nitro-L-arginine methyl ester (L-NAME) or methylene blue reduced the relaxant effect of berberine , and L-arginine (10(-3) M) partially antagonized the effect of L-NAME.”

“Two known inhibitors of endothelium-derived relaxing factor (EDRF), L-NG-nitro arginine (L-NOARG) (a specific inhibitor of nitric oxide formation from L-arginine) and methylene blue (an inhibitor of soluble guanylyl cyclase), significantly attenuated the vasodilator response to berberine.”