Nasal organ

Clanis H. and Key B. (2001). Expression of glycoproteins in the vomero-nasal organ reveals a novel spatiotemporal pattern of sensory neurone maturation. J Neurobiol 46, 113-125. 

Saint Girons H. (1976). Histological study of nasal organs of Crocodylus niloticus and Caiman — Crocodylidae. Zoomorpkol 84, 301-318. 

Three hundred years ago anatomists observed that humans had two tiny dents on either side of the nose cavity and about a centimetre up from the nostrils. This is the vomero-nasal organ (VNO), also known as Jacobson s organ, named after the man who published a detailed description of animal VNOs in 1811. The human VNO has generally been ignored because it was clearly of no importance since there are no nerve connections between it and the brain. It appears to be merely the vestige of some early evolutionary organ. The VNO is very impor-... 

Olfaction, like visual and taste perception, is an ancient process. Olfaction plays a role in sexual arousal. The olfactory system in mammals is remarkable with respect to the number of receptors engaged in monitoring odours. There are several thousand hepta-helical G-protein-coupled receptors in the olfactory epithelium and the nasal organ of a dog, and still about 1000 receptors in the corresponding human organs. It has been estimated that nearly 1% of all genes code for olfactory receptors alone. 

Odors are perceived via the olfactory system, which is composed of two organs in the nose the olfactory epithelium, a very small area in the nasal system, and the trigeminal nerve endings, which are much more widely distributed in the nasal cavity (11). The olfactory epithelium is extremely sensitive, and humans often sniff to bring more odorant in contact with this area. The trigeminal nerves initiate protective reflexes, such as sneezing or interruption of irrhalation, with exposure to noxious odorants. 

A slightly more detailed airway organization suggested by the ICRP Task Group on Lung Dynamics divides the airway into five regions nasal... 

Antihistamines are drags used to counteract the effects of histamine on body organs and structures. Examples of antihistamines include diphenhydramine (Benadryl), loratadine (Claritin), fexofenadine (Allegra), and cetirizine (Zyrtec). A new antihistamine, deslorata-dine (Clarinex), is die active metabolite of loratadine and is intended to eventually replace loratadine (Claritin). Topical corticosteroid nasal sprays such as fluticasone propionate (Flonase) or triamcinolone ace-tonide (Nasacort AQ) are also used for nasal allergy symptoms. See Chapter 56 for more information on die topical corticosteroids. 

These studies on NPYR are typical of the state of the art in cyclic nitrosamine metabolism ai d activation. The major metabolic pathways have been rather well characterized, but data on the relationship of these pathways to carcinogenesis are limited. This is especially true of the organospecific effects of NPYR and the other cyclic nitrosamines. For example, the main target organs for NPYR in the Syrian golden hamster are the trachea and nasal cavity rather than the liver. This is in spite... 

Ritchie (1944) wrote The Organ of Jacobson consists of paired tubular bodies, vascular and richly innervated, lying enclosed in bone in the front of the nasal chamber, and communicating with the nostrils above, and on the other hand with the mouth by two naso-palatine canals which open behind the posterior incisors. It occurs from Amphibia onwards and is probably an accessory organ of smell". 

Fig. 2.4 Displacement of the N-P duct caudally and intra-nasai transfer nasal aperture of the organ (VNd) on the rostral septum in (a) rodents, (b) lagomorphs, and (c) interconnection of VNd i— to N-Pd by sub-septal gutter in rat (from Wysocki and Meredith, 1991 Wohrmann-Repenning, 1981a and b).

Fig. 2.10 Nasal chemoreceptive systems (Rodent) — chemosensory and autonomic fibres Masera s organ (= Septal Organ) and NT, and vasomotor (NP and Ethmoidal) in adult hamster (from Meredith, 1983).

Barone R. and Lombard M. (1966). Organe de Jacobson, nerf vomero-nasal et nerf terminal du chien. Bull Soc Sci Vet Med Comp Lyon, 257-270. 

Clancy A.N., Schoenfeld T., Forbes W. and Macrides F. (1994). The spatial organization of the peripheral olfactory system of the hamster, II receptor surfaces and odorant passageways within the nasal cavity. Brain Res Bull 34, 211-241. 

Fishelson L. and Baranes A. (1997). Ontogenesis and cytomorphology of the nasal olfactory organs in the Oman shark, lago omanensis (Triakidae), in the Gulf of Aqaba. Anat Rec 249, 409-421. 

Hollnagel-Jensen O.C. and Andreasen E. (eds.) (1948). Preface and notes Ouvrages sur l Organe vomero-nasal, etc. Einar Munksgaard, Copenhague, xxxii ill., pp. 175. Einar Munksgaard, Kobenhaven, pp. 163. 

Hummel T., Kiihnau D., Knecht M., Abolmaali N. and Huttenbrink K.B. (1999). The anatomy of the vomeronasal organ characterisation by means of nasal endoscopy and magnetic resonance imaging. Chem Senses 24, abs. 365. 

Kratzing J.E. (1982). The anatomy of the rostral nasal cavity and vomeronasal organ in Tarsipes rostratus (Marsupialia Tarsipedidae). Aust Mammal 5, 211-219. 

Rehorek S.J., Firth B.T. and Hutchinson M.N. (2000). The structure of the nasal chemosensory system in squamate reptiles, 2 Lubricatory capacity of the vomeronasal organ. J Biosci 25, 181-190. 

Tucker D. (1971). Non-olfactory responses from nasal cavity Jacobson s Organ and trigeminal system. In Handbook of Sensory Physiology Chemical Senses, 1. Olfaction (Biedler L., ed.). Springer, Berlin, pp. 151-181. 

Verbeme G. (1976). Chemo-communication among domestic cats mediated by the olfactory and vomero nasal senses, 2 the relation between the function of Jacobson s [vomeronasal] organ and flehmen behaviour. Z Tierpsychol 42, 113-128. 

Zuri I., Fishelson L. and Terkel J. (1998). Morphology and cytology of the nasal ca and vomeronasal organ in juvenile and adult blind Mole rats (Spalax ehrenbe Anat Rec 251, 460-471. 

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