“…Note that some studies had experimental groups for more than one medication. Twelve studies used NG-nitro-L-arginine methyl ester (L-NAME) [10,14,[23][24][25][29][30][31][32]34,36,37], seven studies used methylene blue (MB) [10,23,25,27,28,33,35], two studies used indigo carmine (IC) [25,26], one study used Aminoguanidine (AG) [32], one used 7-Nitroindazole (7-NI) [32] and two used 1H- [1,2,4] Oxadiazole [4,3-a] quinoxalin-1-one (ODQ) [10,23].…”