ABSTRACT
Each of the structures integrating the sense of smell in mammals has a different degree of development, even in the so-called macrosmatic animals, according to the capacity of the olfactory system to detect thousands of different chemical signals. Such morphological diversity implies analogous physiological variation. The study of the accessory olfactory system, also known as the vomeronasal system, is a useful way to analyze the heterogeneity of the sense of smell. Macrodissection and microdissection methods as well as conventional histology and immunohistochemistry protocols were used to study aspects of the vomeronasal organ and the accessory olfactory bulbs in dogs. Observations regarding the end of the anterior part of the vomeronasal duct have been emphasized. Both lectins, Ulex europaeus agglutinin I and Lycopersicum esculentum agglutinin, and one G protein, G(αi2), show a similar pattern of binding in the sensory epithelium of the vomeronasal organ and in the vomeronasal nerve and glomerular layers of the accessory olfactory bulb, whereas the expression of protein G(αo) was not observed. Taken together, our results emphasize the contribution of comparative data to our understanding of the vomeronasal system function.
Subject(s)
Dogs/anatomy & histology , Olfactory Bulb/anatomy & histology , Vomeronasal Organ/anatomy & histology , Animals , Epithelium/anatomy & histology , Epithelium/metabolism , Female , GTP-Binding Protein alpha Subunit, Gi2/metabolism , Immunohistochemistry/methods , Lectins/metabolism , Male , Mice , Mice, Inbred BALB C , Olfactory Bulb/cytology , Olfactory Bulb/metabolism , Vomeronasal Organ/cytology , Vomeronasal Organ/metabolismABSTRACT
The morphology of the soft tissue and supporting cartilage of the vomeronasal organ of the fetal pig was studied from early stages to term. Specimens obtained from an abattoir were aged by crown-to-rump distance. Series of transverse sections show that some time before birth all structures--cartilage, connective tissue, blood vessels, nerves, glands and epithelia--are well developed and very similar in appearance to those of the adult. Furthermore, in transmission electron microscopy photomicrographs obtained at this stage the vomeronasal glands exhibit secretory activity.
