PECILARITIES OF MORPHOGENESIS OF NASAL REGION STRUCTURES IN RATTUS NORVEGICUS

With the purpose to clarify general patterns and species characteristics of prenatal morphogenesis of nasal region structures in rattus norvegicus 21 series of consecutive histological sections preparations of 4,0-36,0 mm parietal-coccygeal length of rattus norvegicus were examined. It has been established that development of nasal cavity in rats begins with nasal placodes with ectodermal origin. The formation of nasal cavity in rats passes five sequential stages: olfactory placode, nasal fossa, nasal sacks, primary nasal cavity and definitive nasal cavity. Formation of nasal cavity includes obligatory process of physiological atresia of nostrils, nasal-palatine channels and ducts of vomeronasal organ. Physiological atresia of these structures proceeds the time when palatine processes become horizontal. Regularities of nasal glands morphogenesis have a certain sequence of development: first lateral nasal gland is laid, then maxillary sinus, respiratory and olfactory glands. In general, development of nasal glands in rats occurs on earlier stages of development, as compared to human.