Chemosensing: selectivity, sensitivity and additive effects on a stimulant-induced activity of olfactory preparations

Ultrastructure of olfactory epithelia in mice after smoke exposure

Olfactory epithelium from three groups of C57B1/6J and SWR/J mice exposed once or twice daily to 10% cigarette smoke for six or nine days was examined at the ultrastructural level. Olfactory epithelium of SWR/J experimental mice was not affected by cigarette smoke. However, prominent alterations were noted in this epithelium of C57B1/6J smoke treated mice. These alterations included a reduction in size and (possibly) number of olfactory vesicles which sometimes failed to protrude above the epithelial surface and greatly reduced numbers of olfactory vesicle sensory cilia. In the supporting cell population an abnormal electron-lucent cell type was noted among the usually darker types. Both cell types were frequently found protruding abnormally above the epithelial surface. Microvilli of supporting cells were markedly reduced in number. The present study revealed that the olfactory epithelia in all mice of the same strain are not affected equally by acute smoke exposures. In affected animals the degree of morphological alteration suggests that normal olfaction might have been impaired. Strain differences in reaction to smoke insult indicate that susceptibility is genetically determined.