PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Lateral Line System”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed2002

Immunohistochemical localization of BDNF-, TrkB- and TrkA-like proteins in the teleost lateral line system.

The lateral line system, formed of both superficial (pit organs) and canal neuromasts, is one of the major mechanosensory systems in fish. It has always been assumed that this system depends on neurotrophins and their cognate Trk receptors for development and maintenance, as has been shown in other mechanosensitive systems of vertebrates. However, until nowthis issue has not been specifically addressed. In this study we used immunohistochemistry to investigate the occurrence and localization both of neurotrophins (NGF-, BDNF- and NT-3-like) and of Trk-like proteins (TrkA-, TrkB-, TrkC-like) in alevins of Salmo salar and S. trutta. All cells in the pit organs of S. salar displayed strong immunoreactivity for TrkB-like and BDNF-like, whereas they were restricted to the hair cells in S. trutta. The hair, supporting and mantle cells of S. salar, and the mantle cells of S. trutta, also expressed TrkA-like immunoreactivity. In the canal neuromasts BDNF-, TrkA- and TrkB-like proteins were present in all cells, without differences between species. NGF-, NT-3- and TrkC-like immunoreactivity were never detected. The present results suggest that mechanoreceptive hair cells, as well as supporting cells, in the lateral line system are under the control of the BDNF-TrkB-like complex, and probably of ligands of TrkA-like receptors.

Animals↗
PubMed1996

Efferent neurons of the lateral line system and their innervation of lateral line branches in a euteleost and an osteoglossomorph.

The efferent neurons of the lateral line system of the euteleost Aplocheilus lineatus and the osteoglossomorph Pantodon buchholzi, both surface feeding fish, were examined by neuronal tract tracing. Besides horse-radish peroxidase, fluorescent dextrans were used as tracers to allow simultaneus visualization of projections from different lateral line branches. Labeled efferent neurons were found in nuclei situated in the medulla ventral of ventricle IV. This position resembles the octa-volateralis efferent nucleus of previous studies. The number of labeled cells in the efferent nucleus is low in both species. Most neurons were found ipsilaterally to the application site, some along the midline and only very few contralaterally. The size of efferent cells differs distinctly between Aplocheilus, possessing small cell-bodies (length 16.5 microm), and Pantodon, which has very large efferent cells (length 47.0 micron). Efferent axon bundles course rostrally in both species, leaving the brain at the level of the anterior lateral line nerve. Only Aplocheilus has in addition lateral axon bundles leaving the brain at the level of the posterior lateral line nerve. After application of one fluorescent tracer to the lateral ramus and a different fluorescent tracer to the superficial ophtalmic ramus in a given animal, double-labeling of efferent cells hardly ever occurs. If the neuromasts I and IV of the dorsal skull of Pantodon are applied with one fluorescent tracer each, approximately 10% of centrally labeled cells are double-labeled. Considering the results of double-labeling, the concept of a differential innervation of lateral line branches is supported and discussed.

Animals↗
PubMed1989

Development of the lateral line system in Xenopus.

The lateral line system of fishes and amphibians consists of numerous epidermal mechano-receptors which are distributed over the whole body surface. As in other amphibians, the lateral line system of Xenopus develops from epidermal placodes situated on the head region of the embryo. The dorsolateralis placodes form a rostro-caudal series of epidermal thickenings centered around the otic placode. In this series, placodes remaining within the epidermis and forming lateral line primordia alternate with lateral line ganglion forming placodes. Each lateral line primordium elongates and migrates within the epidermis along a well-defined pathway, leaving behind a row of small cell groups, the primary lateral line organs. As the ganglion which supplies a given row of organs and the corresponding lateral line primordium originate in spatial contiguity, and as the axons of the lateral line nerve grow out together with the migrating primordium, the lateral line neurones remain in contact with their target cells throughout development. After segregation of a primary organ from a migrating primordium, cell differentiation occurs. Receptor cells establish afferent and efferent synaptic contacts with axons from the lateral line nerve. Apically, a bundle of stereocilia and a single, microtubule-containing kinocilium protrude from the surface of a receptor cell into a jelly-like cupula, which extends into the surrounding fluid. Displacement of the cupula and the concomitant bending of the cilia stimulates the receptor cells. The cilia of a receptor cell are asymmetrically arranged, and this structural polarity is related to the directional sensitivity of the cells. Two types of receptor cells, with opposite orientations, are intermingled within each organ, giving the whole organ a bidirectional sensitivity. The number of lateral line organs is increased by the process of accessory organ formation, where primary organs grow and divide to produce secondary organs. In this way, existing rows of organs are extended. Moreover, single primary organs are transformed into elongate plaques of closely apposed organs. The lateral line system has reached its greatest extent at late larval stages. During metamorphosis, the number of organ plaques is reduced in some lines, and one line even disappears completely. Two large, myelinated afferent fibers innervate a whole organ plaque. They branch repeatedly to supply every organ of the plaque, and each fiber is thought to innervate only receptor cells of the same polarity.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed2004

Development of the lateral line system in the shovelnose sturgeon.

The lateral line systems of aquatic amphibians and all chondrichthyan and osteichthyan fish present a similar array of mechanoreceptors. However, electroreceptors, the second major component of the lateral line system, have clearly undergone more significant evolutionary change. Chondrichthyans and non-neopterygian fish possess primitive ampullary organ electroreceptors, whereas significantly different 'new' ampullary organs and tuberous electroreceptors are found in a few groups of teleosts (mormyrids, gymnotids and some catfish). The pairing of mechano- and electroreceptors in the lateral line system, as well as the morphologically and physiologically distinct electroreceptors of teleosts have inspired several recent studies on the origin and evolution of the lateral line receptors. We described the development of the lateral line system in sturgeon (Scaphirhynchus platorynchus) as part of an outgroup analysis of lateral line development in three taxa: vertebrates that have both mechanoreceptive neuromasts and primitive electroreceptors; neopterygian fish that only have mechanoreceptors; and teleosts that have re-evolved new electroreceptors. Development in Scaphirhynchus was consistent with previously studied taxa in that the lateral line system developed from a series of six dorsolateral placodes. Interestingly, we found that the octaval placode was bound rostrally and caudally by large placodal fields, out of which the six lateral line placodes arose. This finding supports recent suggestions for a common placodal primordium for all placodes. Each of the six placodes gave rise to the lateral line nerves before elongating into sensory ridges, which contained neuromast primordia. The ampullary organ fields of Scaphirhynchus arose from the lateral zones of the anterodorsal, anteroventral, otic and supratemporal sensory ridges, which is also consistent with recently studied taxa. Comparisons of the lateral line system of Scaphirhynchus and close relatives, Acipenser and Polyodon, indicate that variation in some aspects of lateral line receptor numbers and distribution are related to changes in head morphology and feeding strategy, whereas other changes, such as a reduction in receptor number without a change in placode field size, indicate changes in placode development.

Animals↗
PubMedDate not supplied

Information-processing demands in electrosensory and mechanosensory lateral line systems.

The electrosensory and mechanosensory lateral line systems of fish exhibit many common features in their structural and functional organization, both at the sensory periphery as well as in central processing pathways. These two sensory systems also appear to play similar roles in many behavioral tasks such as prey capture, orientation with respect to external environmental cues, navigation in low-light conditions, and mediation of interactions with nearby animals. In this paper, we briefly review key morphological, physiological, and behavioral aspects of these two closely related sensory systems. We present arguments that the information processing demands associated with spatial processing are likely to be quite similar, due largely to the spatial organization of both systems and the predominantly dipolar nature of many electrosensory and mechanosensory stimulus fields. Demands associated with temporal processing may be quite different, however, due primarily to differences in the physical bases of electrosensory and mechanosensory stimuli (e.g. speed of transmission). With a better sense of the information processing requirements, we turn our attention to an analysis of the functional organization of the associated first-order sensory nuclei in the hindbrain, including the medial octavolateral nucleus (MON), dorsal octavolateral nucleus (DON), and electrosensory lateral line lobe (ELL). One common feature of these systems is a set of neural mechanisms for improving signal-to-noise ratios, including mechanisms for adaptive suppression of reafferent signals. This comparative analysis provides new insights into how the nervous system extracts biologically significant information from dipolar stimulus fields in order to solve a variety of behaviorally relevant problems faced by aquatic animals.

Action Potentials↗
PubMed2004

S100 protein is a useful and specific marker for hair cells of the lateral line system in postembryonic zebrafish.

The neuromast of the lateral line system of zebrafish has become an ideal model for the study of both developmental genetics and the vertebrate auditory system. Interestingly, the hair cells of this system have been found to selectively display immunoreactivity for S100 protein in some teleosts. In order to provide a selective marker for the sensory cells of the lateral line system, we have analyzed immunohistochemically the expression of S100 protein in zebrafish from the larval to the adult stage. In larval and adult animals S100 protein immunoreactivity was detected restricted to the hair cells of both superficial and canal neuromasts. Apparently the expression of S100 protein by hair cells was independent of the age, but it was expressed heterogeneously in the hair cells of canal neuromasts. The results of this work provide a feasible method to easily identify sensory cells in the neuromasts, and may be of interest in studies regarding development, differentiation or turnover of hair cells.

Animals↗
PubMed1989

Gross morphology and evolution of the mechanoreceptive lateral-line system in teleost fishes.

The morphology and development of the mechanoreceptive lateral-line system in teleost fishes is reviewed, and the systematic distribution of defined types of lateral-line systems is summarized. The importance of an understanding of ontogeny is stressed and the roles of phylogenetic and developmental constraints in the evolution of the lateral-line system are discussed. Four types of head canal systems are identified on the basis of the relative development of the canals and the orientation of the neuromast receptors contained within them. The distribution of these patterns in the four major teleost clades is analyzed. It is suggested that a branched tubule system associated with the head canals is a primitive teleost character, while widened and reduced head canal patterns are convergent functional specializations in many taxa. The trunk canals are contained in a continuous series of lateral-line scales, and eight trunk canal patterns are described in teleosts. Given the correlation of the systematic distribution of the different trunk canal patterns, ecological habit and body shape, it appears that the trunk canals may function as a hydrodynamic monitor in swimming fishes.

Animals↗
PubMed2005

Cell proliferation in the developing lateral line system of zebrafish embryos.

The sensory organs of the embryonic lateral line system are deposited by migrating primordia that originate in the otic region. Here, we examine the pattern of cell proliferation in the posterior lateral line system. We conclude that three phases of cell proliferation are involved in the generation of this system, separated by two phases of mitotic quiescence. The first phase corresponds to generalized proliferation during gastrulation, followed by a first period of quiescence that may be related to the determination of the lateral line precursor cells. A second phase of proliferation takes place in the placode and migrating primordium. This region is organized in annuli that correspond to the expression of proneural/neurogenic genes. A second period of quiescence follows, corresponding to deposition and differentiation of the sensory organs. The third period of proliferation corresponds to continued renewal of hair cells by division of support cells within each sensory organ.

Animals↗
PubMed1987

Metamorphic changes within the lateral-line system of Anura.

The metamorphic loss of lateral-line organs, lateral-line nerves and second order lateral-line neurons was examined in two Anuran species. At the onset of metamorphic climax, terminals within the lateral-line neuropil showed accumulation of glycogen-like granules. Neither the lateral-line nerve nor the organs or the nerve terminals inside the organs displayed any sign of degeneration at this stage. A few second order neurons exhibited accumulations of chromatin into conspicuous masses. These cells were partially or completely engulfed by phagocytes. At mid-metamorphosis all lateral-line organs were lost. The proximal parts of the lateral-line nerve fibers entering the rhombencephalic alar plate showed signs of degeneration. Within the lateral-line neuropil, pre- and some postsynaptic elements exhibited the flocculent type of degeneration or, to a lesser extent, the dark type of degeneration. Second order lateral-line neurons underwent an electron-dense or electron-lucent type of degeneration and were taken up by phagocytes. At the end of metamorphic climax the distal parts of the lateral-line nerves showed numerous dark degenerating fibers inside an intact myelin sheath. Within the lateral-line neuropil, numerous dark degenerating presynaptic elements were found next to some elements showing flocculent degeneration. Fewer degenerating second order neurons were found in the alar plate. They showed predominantly the dark type of degeneration. In contrast to earlier reports, our data suggest that the degenerative metamorphic changes observed in the present study are initiated in all parts of the lateral-line system simultaneously, and lead to the complete loss of all lateral-line organs and nerves and presumably all second order lateral-line neurons as well.

Animals↗
PubMed1998

Dipole source localization by mottled sculpin. III. Orientation after site-specific, unilateral denervation of the lateral line system.

To test the hypothesis that spatial excitation patterns along the lateral-line system underlie source localization, we videotaped the orientation behavior of blinded mottled sculpin in response to a small dipole source (50-Hz vibrating sphere) before and after unilateral denervation of the lateral line system on different body regions (head, trunk and head + trunk). Approach pathways were qualitatively similar to those followed by normal intact animals. Abnormal behavior (turning in circles) was not observed. However, the frequency with which fish placed their intact side facing the source increased by 12-89%, depending on the denervation site. The angular accuracy of orientation decreased by 20 degrees to 60 degrees (100% to 370% change) depending on source location and region of lateral line denervated. Deficits tended to be site-specific. For example, unilaterally denervating lateral-line organs on the head resulted in less accurate orienting responses when the source was located on the denervated side of the head, but not on the opposite side of the head or on either side of the trunk. Site-specific deficits and the absence of abnormal approach pathways argue that animals are relying on a point-by-point spatial representation of source location along the sensory surface rather than computations based on bilateral comparisons.

Animals↗
PubMed1984

Peripheral configuration and central projections of the lateral line system in Astronotus ocellatus (Cichlidae): a nonelectroreceptive teleost.

The lateral line system of Astronotus ocellatus comprises one trunk canal, one tail canal, and three head canals. The sensory receptors on the head are innervated by rami of the dorsal anterior, ventral anterior, and posterior lateral line nerves, and those along the trunk and tail by rami of the posterior lateral line nerve. The peripheral configuration of lateral line canals and nerves was examined in whole mount preparations, the central connections of restricted groups of endorgans studied using HRP and degeneration methods, and the neuronal morphology and cytoarchitecture of the lateralis region investigated with Nissl, silver, and Golgi methods. Neurons of the lateralis cell column are diffusely arrayed and of variable morphology. They are oriented primarily in the transverse plane and, with the exception of a dorsal lamina of large multipolar cells, are not organized into zones. Lateralis fibers bifurcate on entering the brainstem, course in lateral tracts, and give off medially directed collaterals to terminate in the ipsilateral nucleus medialis and nucleus caudalis. In addition, fibers terminate in the eminentia granularis of the cerebellum, but only fibers supplying endorgans in the head canals penetrate the granule cell zone of the cerebellar corpus. Fibers supplying sense organs in adjacent canals overlap in their central endings, whereas fibers of distantly separated receptors do not overlap. The rami supplying trunk and tail canal organs do not project as far rostrally in the central neuropil as do the other rami. Endings of posterior lateral line fibers lie dorsal to those of the anterior lateral line nerves, and some lateralis fibers terminate within the confines of the magnocellular, descending, and posterior nuclei of the octavus column. Although there is spatial order to the lateralis projections, there is no clear somatotopic organization in the lateralis region.

Afferent Pathways↗
PubMed2003

Cadherin-1, -2 and -4 expression in the cranial ganglia and lateral line system of developing zebrafish.

Cadherins are cell adhesion molecules that play important roles in development of a variety of tissues and organs including the nervous system. In this study we analyzed expression patterns of three zebrafish classical (type I) cadherins (cadherin-1, -2, and -4) in the embryonic zebrafish cranial ganglia and lateral line system using in situ hybridization and immunohistochemical methods. All three cadherins exhibit distinct spatiotemporal patterns of expression during cranial ganglia and lateral line system development. cadherin-1 message was detected in the trigeminal and facial ganglia, in the lateral line ganglia, and in most of neuromasts in the lateral lines. Cadherin-2 mRNA and protein were expressed by the majority of the cranial ganglia and lateral line system. Both cadherins were found in embryos younger than 24 hours post fertilization as well as in 2-3-day old embryos and larvae. In contrast, cadherin-4 mRNA and protein expression was detected in embryos older than 30 hours post fertilization and limited to the trigeminal, statoacoustic, and vagal cranial ganglia, and the lateral line ganglia of older embryos and larvae.

Animals↗
PubMed1993

Source level discrimination by the lateral line system of the mottled sculpin, Cottus bairdi.

A conditioned feeding response of the mottled sculpin was used to measure level discrimination by the lateral line system as a function of source level, frequency, and distance. Level discrimination limens (LDLs) were determined with a 6-mm-diam, sinusoidally vibrating sphere placed in front of the trunk lateral line system at varying distances from the trunk of the fish. LDLs were relatively independent of frequency over most of the detection bandwidth, with mean values ranging from 5-6 dB from 10 to 50 Hz at a fish-to-source distance of 15 mm. The mean LDL at 100 Hz, near the upper end of the frequency range of the lateral line system was 8-9 dB at the same source distance. Mean LDLs at 10 and 20 dB above detection threshold were not significantly different, nor were mean LDLs at distances ranging from 7.5 to 30 mm for a 50-Hz, 10-dB SL source. The level-encoding features of posterior lateral line fibers innervating the trunk were also determined from data previously collected under stimulus conditions nearly identical to those used for behavioral studies. Afferent fibers responded to level increments with increases in both spike rate and phase-locking over most of the conditions used in behavioral experiments. Although it was impossible to eliminate spike rate as a level-encoding mechanism at any stimulus condition, phase-locking appeared to be a strong candidate at low source levels and vibration frequencies.(ABSTRACT TRUNCATED AT 250 WORDS)

Acoustic Stimulation↗
PubMed1987

Anatomy and differential growth of the lateral line system of the mottled sculpin, Cottus bairdi (Scorpaeniformes: Cottidae).

Scanning electron microscopy and standard histological techniques were used to describe the basic anatomy and postembryonic growth of the lateral line system of Cottus bairdi. The gross anatomy and distribution of lateral line neuromasts in canals and superficially on the skin are similar to what has been reported for many primitive actinopterygian fishes. Both canal and superficial neuromasts showed postembryonic growth in the number of hair cells and size of neuromasts, but canal neuromasts grew more elongate whereas superficial neuromast grew symmetrically. Neuromasts in the mandibular canal grew significantly faster than any other neuromasts and superficial neuromasts on the head showed the least amount of growth. Differential growth of the sculpin lateral line system may be related to the feeding behavior of the animal and to differences in the ambient levels of water noise to which larval and adult fish are exposed.

Animals↗
PubMed1988

Processing of wave patterns in the lateral line system parallels to auditory processing.

Processing of wave patterns in the lateral line system is reviewed with particular reference to similarities with auditory processing. Four levels are considered: the receptor cell, stimulus parameter encoding in the afferent nerve, the neural organization of stimulus localization, and analysis of complex waves. The high degree of parallelism at all these levels to auditory processing is considered as a strong evidence for a common evolutionary origin of these two systems.

Acoustic Stimulation↗
PubMed2006

Epidermal growth factor (EGF) expression in lateral line system and in taste buds of adult zebrafish (Brachidanio rerio).

The mechano and chemosensory organs of adult teleosts undergoes a continuous cell renewal and turnover which is regulated in part by growth factors. Here, we investigated the occurrence and the cell localization of epidermal growth factor (EGF) in the lateral line system and taste bud of adult zebrafish, using Western blot and immunohistochemistry associated to a polyclonal antibody against mammalian EGF. Furthermore, the distribution of S100 protein was studied in parallel to label hair sensory cells in the lateral line system. Western blot revealed one unique protein band with an estimated molecular weight of about 13 kDa, equivalent to the EGF of mammals. Specific immunoreactivity for EGF was observed in the epithelial basal and/or supporting cells of the neuromasts of the lateral line system and taste buds. Conversely, the sensory cells in both sensory structures were devoid of immunostaining. Present results demonstrate the occurrence of EGF in mechano and sensory system of adult zebrafish, suggesting a role for this molecule in the cell renewal and turnover of these structures.

Animals↗
PubMed1983

Development of the lateral line system in Xenopus laevis. I. Normal development and cell movement in the supraorbital system.

During development of Xenopus laevis, the supraorbital lateral line system (i.e. the parietal and supraorbital lines of organs and the anterior auditory group of organs) is all derived from a single primordium located in the ear region of the epidermis. The primordium elongates first by active movement along the dorsal margin of the eye. Individual primary organs are then formed by progressive fragmentation of the streak-like primordium. After fragmentation, passive displacement of the organs due to skin growth seems to play the main role in altering the arrangement of the line system. Transplantation experiments confirmed that non-placodal epidermal cells are not incorporated into the developing system. The active elongation of the primordium is due to cell multiplication, and not due to cell rearrangement or change in cell shape or size. Cell multiplication is not confined to a growth zone, but dividing cells are randomly distributed throughout the primordium. All cells of a primordium have to change position during its elongation.

Animals↗