Abstract
The present work demonstrates the toxic action of neomycin on the olfactory epithelium after both local and intraperitoneal administration. The most severe changes are observed in the proximal part of the epithelium of intraperitoneal administration, whereas the changes are more extensive near the free surface of the epithelium after local administration. In the supporting cells there is an increase in the number of mitochondria, lysosomes, double membranes, myelin figures and agranular vesicles, and a lengthening of the microvilli. In the receptor cells there is degeneration of the mitochondria and the outer membranes and vesicles of the cilia as well as an increased formation of centrioles. The significance of these changes for the olfactory function is discussed.