The aim of this work was to determine the localization of nicotinamide-adenine dinucleotide phosphate-diaphorase (NADPH-d) activity as the marker for synthesis of nitric oxide synthase (NOS) in the rat thymus after the application of retinoid acid (RA) on 1st. 7th. 14th and 21st days of gestation. The given results can build the basis for understanding of the role of NOS in rat thymus. https://herbsdailyes.shop/product-category/nipple-creams/