Light and electron microscopic observations on the normal structure of the vomeronasal organ of garter snakes
TL;DR: The vomeronasal cell column is the structural unit of the organ and may represent the dynamic unit for cell replacement as well and a sequential process of cell proliferation, neuronal differentiation, and maturation appears to occur in the epithelium despite the adult state of the animal.
Abstract: The vomeronasal epithelium of adult garter snakes (Thamnophis sirtalis and T. radix) was studied by light and electron microscopy. The sensory epithelium is extraordinarily thick, consisting of a supporting cell layer, a bipolar cell layer, and an undifferentiated cell layer. The supporting cell layer is situated along the luminal surface and includes supporting cells and the peripheral processes (dendrites) of bipolar neurons. The luminal surfaces of both supporting cells and bipolar neurons are covered with microvilli. Specializations of membrane junctions are always observed between adjacent cells in the subluminal region. Below the supporting cell layer, the epithelium is characterized by a columnar organization. Each column contains a population of bipolar neurons and undifferentiated cells. These cells are isolated from the underlying vascular and pigmented connective tissue by the presence of a thin sheath of satellite cells and a basal lamina. Heterogeneity of cell morphology occurs within each cell column. Generative and undifferentiated cells occupy the basal regions and mature neurons occupy the apical regions. Transitional changes in cell morphology occur within the depth of each cell column. These observations suggest that the vomeronasal cell column is the structural unit of the organ and may represent the dynamic unit for cell replacement as well. A sequential process of cell proliferation, neuronal differentiation, and maturation appears to occur in the epithelium despite the adult state of the animal.
Citations
More filters
TL;DR: New anatomical studies of the central pathways of the olfactory and vomeronasal systems indicated that these two systems converge on neurons in the telencephalon, providing an anatomical substrate for functional interactions.
587 citations
TL;DR: A comprehensive review of the biophysical and electrophysiological evidence regarding the transduction processes as well as subsequent signal processing and spike generation in ORNs is presented.
Abstract: Schild, Detlev, and Diego Restrepo. Transduction Mechanisms in Vertebrate Olfactory Receptor Cells. Physiol. Rev. 78: 429–466, 1998. — Considerable progress has been made in the understanding of tr...
471 citations
TL;DR: The present review gives a short description of the discovery of the vomeronasal organ and the pivotal findings of Jacobson, and the anatomical, biochemical and functional properties of the receptor neurones are described.
Abstract: Many animals use their vomeronasal organs to gain direct and specific contact with chemical cues released by congeners and in biological fluids. These cues provide information about the physiological status of the emitter and facilitate or regulate social interactions such as sexual relationships. The present review gives a short description of the discovery of the vomeronasal organ and the pivotal findings of Jacobson. The distribution of the organ and its anatomy in some vertebrates are described. The mechanisms for stimulus entry and egress are discussed, and the findings that led to the appreciation of the vomeronasal organ in mammals as a main chemosensory organ for pheromones mediating reproductive status and inducing sexual behaviour are reported. The anatomical, biochemical and functional properties of the receptor neurones are described.
245 citations
TL;DR: Both G protein antibodies stained the microvillar surface of the epithelium and the nerve bundles in the subepithelial mucosa in the vomeronasal organ of Brazilian opossums.
179 citations
TL;DR: A phylogenetic analysis of central olfactory projections indicates that at least three distinct olf factory subsystems may be broadly present in vertebrates and that a fourth, the accessory vomeronasal system, arose in tetrapods.
Abstract: The general features of the olfactory system are remarkably consistent across vertebrates. A phylogenetic analysis of central olfactory projections indicates that at least three distinct olfactory subsystems may be broadly present in vertebrates and that a fourth, the accessory olfactory or vomeronasal system, arose in tetrapods. The origin and function of the vomeronasal system have been the subject of much controversy, but some conclusions can be drawn. The vomeronasal system did not arise as an adaptation to terrestrial life, as indicated by the presence of a vomeronasal system in modern aquatic amphibians and the increasing paleontological evidence that the last common ancestor of amphibians and amniotes was aquatic. The vomeronasal system is involved in both foraging and reproductive behaviors in reptiles and has been shown to be involved in some pheromonally mediated behaviors in mammals. However, among mammals, some pheromonal responses are not mediated by the vomeronasal system, and the possible involvement of the vomeronasal system in other type of behaviors has not yet been investigated. Thus, the relative functions of the olfactory and vomeronasal systems of tetrapods remain unclear. Other hypotheses that features of the olfactory system are specialized for aquatic chemoreception or for pheromone detection are similarly insupportable. For example, the suggestion that members of the olfactory receptor family can be separated into two groups that function for transduction of air-borne or water-borne odorants is contradicted by the presence of both groups in aquatic amphibians and by a phylogenetic analysis of the sequences for these genes. Interestingly, the putative odorant receptors from the vomeronasal epithelium share little sequence similarity with those from the olfactory epithelium, indicating that these receptors may have been independently co-opted from the larger family of seven transmembrane domain receptors for use in odor transduction. A phylogenetic analysis of the distribution of olfactory receptor cell types indicates that microvillar olfactory receptor cells are widespread among vertebrates and are not restricted to aquatic animals or to the vomeronasal epithelium of tetrapods. Previous suggestions that all microvillar receptor cells are specialized for the detection of pheromones are not tenable. Attempts to recognize features of the olfactory system that are common to all vertebrates and might be specialized for the detection of pheromones vs. more general odorants, or for the detection of water-borne vs. air-borne odorants, are not supported by current evidence.
175 citations
References
More filters
TL;DR: Three species were studied, the rabbit, opossum and rat, and the topographic segregation of the areas of termination of the olfactory and accessory ofactory (vomeronasal) projections is suggestive of a functional dichotomy in the organization of the wreath system.
Abstract: Three species were studied, the rabbit, opossum and rat. Lesions of the main olfactory bulb caused terminal degeneration, assayed by the Fink-Heimer method, to occur in the ipsilateral olfactory tubercle, prepyriform cortex (including its periamygdaloid part), ventrolateral entorhinal area, and in anterior and posterolateral divisions of the cortical amygdaloid nucleus. The various parts of the ipsilateral anterior olfactory nucleus and the rostroventral end of the anterior continuation of the hippocampus (hippocampal rudiment) also received this projection. Lesions of the accessory olfactory bulb, which receives its sensory input from the vomeronasal (Jacobson's) organ, caused terminal degeneration to occur in the medial amygdaloid nucleus and in a posteromedial part of the cortical amygdaloid nucleus. This projection was conveyed by an accessory olfactory tract, which is accompanied in part of its course by a small nucleus, the bed nucleus of the accessory olfactory tract. The accessory olfactory tract is initially a part of the lateral olfactory tract but becomes increasingly indivuated at more posterior levels. It parts company with the lateral olfactory tract at the rostral end of the amygdaloid region, and, in addition to distributing to the medio-cortical amygdaloid region, it enters the stria terminalis to terminate in the bed nucleus of the stria terminalis in a small region bearing cytoarchitectonic resemblance to the medial amygdaloid nucleus. The topographic segregation of the areas of termination of the olfactory and accessory olfactory (vomeronasal) projections is suggestive of a functional dichotomy in the organization of the olfactory system...
957 citations
Book•
01 Jan 1958
TL;DR: This is a book that will, of course, date, because it is so full of detail, but it does faithfully represent the very best in modem British gynaecological practice.
Abstract: Edited by ALECK BOURNE. Second edition. Pp. xii + 89I, illustrated. London: William Heinemann (Medical Books) Ltd. 1958. 1O5s. net. (The obstetric section edited by Sir Eardley Holland is not the subject of this review.) Professor Jeffcoate's new chapter on disorders of menstruation apparently flows from his pen with such ease that one knows the writing must have been painstaking in the extreme. It is beautifully done and it is not only a delight to read, but it is informative, lucid, scientific, orderly, logical and extremely well illustrated. If it be the tour de force in the book, as I believe it is, it is in good company beside such chapters as Wilfred Shaw's chapter on the ovary and broad ligament revised by John Howkins and John Stallworthy's chapter on genital tuberculosis. These are authoritative and informative. But if these chapters have been picked out, it is not to say that the others are not of a high standard, too, for they are. This is a book that will, of course, date, because it is so full of detail, but it does faithfully represent the very best in modem British gynaecological practice. Mr. Bourne and his publishers, as well as his collaborators, are to be congratulated on surpassing even their previous excellent achievement. E.E.P.
366 citations
TL;DR: It is demonstrated that peripheral deafferentation of the vomeronasal system produces severe sexual behavior deficits in approximately one-third of the treated animals, the first experimental demonstration of a functional role for the vOMS organ in a mammalian species.
Abstract: Sexual behavior in male hamsters is totally abolished by bilateral removal of the olfactory bulbs. This operation eliminates sensory input from both the olfactory and the vomeronasal systems. We previously demonstrated that peripheral destruction of the olfactory receptors caused anosmia but did not impair male hamster mating behavior. Here we demonstrate that peripheral deafferentation of the vomeronasal system produces severe sexual behavior deficits in approximately one-third of the treated animals. Combined deafferentation of both the vomeronasal and the olfactory systems eliminates copulation in 100 percent of the animals. This is the first experimental demonstration of a functional role for the vomeronasal organ in a mammalian species.
347 citations