Intranasal delivery of siRNA to the olfactory bulbs of mice via the olfactory nerve pathway

► Intranasal siRNA penetrates the olfactory epithelium and lamina propria. ► The olfactory nerve mediates intranasal delivery of siRNA to the olfactory bulb. ► Intranasal siRNA distributes in olfactory nerve, glomerular and mitral cell layers. ► Results support potential applications of intranasal siRNA for silencing in CNS.