Selective activation of carcinogens and other toxicants by nasal mucosae

Abstract

Nasal cytochrome P-450 occurs in dogs, rats, monkeys, rabbits, mice, Syrian hamsters, guinea pigs (Table 1), and probably in most, if not all, mammals. In many species the concentration of cytochrome P450, averaged over the entire epithelium of the nasal cavity, is second only to that of liver (Hadley & Dahl, 1983). Concentrations of P-450 in the olfactory mucosa in monkeys, dogs, rabbits, and rats — the only species in which intranasal regional distribution has been studied — were much higher than those in nasal respiratory mucosa. In fact, no cytochrome P-450 was found in the nasal respiratory mucosa in cynomologus monkeys. In dogs, no cytochrome P-450 was detected in the vomeronasal organ (A.R. Dahl, unpublished) although this organ is known to contain high concentrations of smooth endoplasmic reticulum in which cytochrome P-450 usually occurs (Graziadei, 1977). The vomeronasal organs in other species were not examined for P-450 content.KeywordsPolycyclic Aromatic HydrocarbonNasal MucosaSyrian HamsterSyrian Golden HamsterVomeronasal OrganThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.