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B. U. Budelmann - One of the best experts on this subject based on the ideXlab platform.
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Structure and function of the Nautilus Statocyst
Philosophical Transactions of the Royal Society B, 1997Co-Authors: Heike Neumeister, B. U. BudelmannAbstract:The two equilibrium receptor organs (Statocysts) of Nautilus are avoid sacks, half-filled with numerous small, free-moving statoconia and half with endolymph. The inner surface of each Statocyst is lined with 130,000-150,000 primary sensory hair cells. The hair cells are of two morphological types. Type A hair cells carry 10-15 kinocilia arranged in a single ciliary row; they are present in the ventral half of the Statocyst. Type B hair cells carry 8-10 irregularly arranged kinocilia; they are present in the dorsal half of the Statocyst. Both type of hair cells are morphologically polarized. To test whether these features allow the Nautilus Statocyst to sense angular accelerations, behavioural experiments were performed to measure Statocyst-dependent funnel movements during sinusoidal oscillations of restrained Nautilus around a vertical body axis. Such dynamic rotatory stimulation caused horizontal phase-locked movements of the funnel. The funnel movements were either in the same direction (compensatory funnel response), or in the opposite direction (funnel follow response) to that of the applied rotation. Compensatory funnel movements were also seen during optokinetic stimulation (with a black and white stripe pattern) and during stimulations in which optokinetic and Statocyst stimulations were combined. These morphological and behavioural findings show that the Statocysts of Nautilus, in addition to their function as gravity receptor organs, are able to detect rotatory movements (angular accelerations) without the specialized receptor systems (crista/cupula systems) that are found in the Statocysts of coleoid cephalopods. The findings further indicate that both Statocyst and visual inputs control compensatory funnel movements.
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The effect of L-glutamate on the afferent resting activity in the cephalopod Statocyst.
Brain research, 1994Co-Authors: B. U. BudelmannAbstract:The effects of bath application of L-glutamate and of excitatory amino acid agonists and antagonists on the resting activity of afferent crista fibers were studied in isolated preparations of the Statocyst of the cuttlefish, Sepia officinalis. L-Glutamate (threshold 10(-5) M) and its agonists quisqualate and kainate (thresholds 10(-6) M) increased the resting activity in a dose-dependent manner. Glutamine (threshold 10(-5) M) was also excitatory, while D-glutamate had no effect. Also, no obvious excitatory effects were seen for NMDA and L-aspartate, nor was any antagonistic effect seen for the selective NMDA-receptor antagonist D-2-amino-5-phosphonovaleric acid (D-AP-5). The spider toxin Argiotoxin636 (threshold 10(-11) M), 2-amino-4-phosphonobutyric acid (AP-4), glutamic acid diethyl ester (GDEE), gamma-D-glutamylaminomethyl-sulfonic acid (GAMS), and kynurenic acid decreased the resting activity and effectively blocked or reversed the effect of L-glutamate and its non-NMDA agonists. Preliminary experiments with Statocysts from the squid Sepioteuthis lessoniana and the octopod Octopus bimaculoides gave comparable results. All data show that in cephalopod Statocysts L-glutamate, via non-NMDA receptors, has an excitatory effect on the activity of afferent fibers, an effect consistent with its possible function as a hair cell transmitter.
Michel André - One of the best experts on this subject based on the ideXlab platform.
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Ultrastructural damage of Loligo vulgaris and Illex coindetii Statocysts after low frequency sound exposure.
PloS one, 2013Co-Authors: Marta Solé, Marc Lenoir, Mercè Durfort, Manel López-bejar, Antoni Lombarte, Michel AndréAbstract:There is a considerable lack of information concerning marine invertebrate sensitivity to sound exposure. However, recent findings on cuttlefish and octopi showed that exposure to artificial noise had a direct consequence on the functionality and physiology of the Statocysts, sensory organs, which are responsible for their equilibrium and movements in the water column. Owing to a lack of available data on deep diving cephalopod species, we conducted a noise exposure comparative experiment on one Mediterranean squid, Illex coindetii, and on the European squid Loligo vulgaris. Scanning electron microscopy (SEM) revealed similar injuries in the inner structure of the Statocysts, as those found in cuttlefish and octopi. In addition to the ultrastructural description of the lesions, we publish here the first images of the crista-cupula system and inner Statocyst cavity of I. coindetii.
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RMI (A) and LM (B-D).
2013Co-Authors: Marta Solé, Marc Lenoir, Mercè Durfort, Manel López-bejar, Antoni Lombarte, Michel AndréAbstract:Decapods Statocyst location in the cephalic cartilage. A: Coronal view –anterior section- of squid (L. vulgaris) head. B, C: Photomicrograps of decapod Statocyst structure. Upper view in the opened Loligo vulgaris Statocyst. B shows the statocyt attached to the macula statica princeps and a statoconia attached to the superior macula neglecta. In C the Statocyst was removed and the macula statica princeps is visible. D: L. vulgaris statolith. (B: Brain, cc: cranial cartilage, e: eye, es: oesophagus, m: mouth, psg: posteror salivary gland, st: Statocyst. ST: Statolith. Sc: statoconia. M: Macula statica princeps). Scale bars: A = 2 cm. B, C = 2 mm. D =1 mm.
André Michel - One of the best experts on this subject based on the ideXlab platform.
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Offshore exposure experiments on cuttlefish indicate received sound pressure and particle motion levels associated with acoustic trauma
'Springer Science and Business Media LLC', 2017Co-Authors: Solé Carbonell Marta, Lenoir Marc, Sigray Peter, Van Der Schaar, Mike Connor Roger Malcolm, Lalander Emilia, André MichelAbstract:Recent findings on cephalopods in laboratory conditions showed that exposure to artificial noise had a direct consequence on the Statocyst, sensory organs, which are responsible for their equilibrium and movements in the water column. The question remained about the contribution of the consequent near-field particle motion influence from the tank walls, to the triggering of the trauma. Offshore noise controlled exposure experiments (CEE) on common cuttlefish (Sepia officinalis), were conducted at three different depths and distances from the source and particle motion and sound pressure measurements were performed at each location. Scanning electron microscopy (SEM) revealed injuries in Statocysts, which severity was quantified and found to be proportional to the distance to the transducer. These findings are the first evidence of cephalopods sensitivity to anthropogenic noise sources in their natural habitat. From the measured received power spectrum of the sweep, it was possible to determine that the animals were exposed at levels ranging from 139 to 142¿dB re 1¿µPa2 and from 139 to 141 dB re 1¿µPa2, at 1/3 octave bands centred at 315¿Hz and 400¿Hz, respectively. These results could therefore be considered a coherent threshold estimation of noise levels that can trigger acoustic trauma in cephalopods
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Offshore exposure experiments on cuttlefish indicate received sound pressure and particle motion levels associated with acoustic trauma
'Springer Science and Business Media LLC', 2017Co-Authors: Solé Carbonell Marta, Lenoir Marc, Sigray Peter, Van Der Schaar, Mike Connor Roger Malcolm, Lalander Emilia, André MichelAbstract:Recent findings on cephalopods in laboratory conditions showed that exposure to artificial noise had a direct consequence on the Statocyst, sensory organs, which are responsible for their equilibrium and movements in the water column. The question remained about the contribution of the consequent near-field particle motion influence from the tank walls, to the triggering of the trauma. Offshore noise controlled exposure experiments (CEE) on common cuttlefish (Sepia officinalis), were conducted at three different depths and distances from the source and particle motion and sound pressure measurements were performed at each location. Scanning electron microscopy (SEM) revealed injuries in Statocysts, which severity was quantified and found to be proportional to the distance to the transducer. These findings are the first evidence of cephalopods sensitivity to anthropogenic noise sources in their natural habitat. From the measured received power spectrum of the sweep, it was possible to determine that the animals were exposed at levels ranging from 139 to 142¿dB re 1¿µPa2 and from 139 to 141 dB re 1¿µPa2, at 1/3 octave bands centred at 315¿Hz and 400¿Hz, respectively. These results could therefore be considered a coherent threshold estimation of noise levels that can trigger acoustic trauma in cephalopods.Postprint (published version
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Ultrastructural damage of "loligo vulgaris" and "illex coindetii" Statocysts after low frequency sound exposure
'Public Library of Science (PLoS)', 2013Co-Authors: Solé Carbonell Marta, Lenoir Marc, Durfort Mercè, López Bejar Manel, Lombarte Carrera Antonio, André MichelAbstract:There is a considerable lack of information concerning marine invertebrate sensitivity to sound exposure. However, recent findings on cuttlefish and octopi showed that exposure to artificial noise had a direct consequence on the functionality and physiology of the Statocysts, sensory organs, which are responsible for their equilibrium and movements in the water column. Owing to a lack of available data on deep diving cephalopod species, we conducted a noise exposure comparative experiment on one Mediterranean squid, Illex coindetii, and on the European squid Loligo vulgaris. Scanning electron microscopy (SEM) revealed similar injuries in the inner structure of the Statocysts, as those found in cuttlefish and octopi. In addition to the ultrastructural description of the lesions, we publish here the first images of the crista-cupula system and inner Statocyst cavity of I. coindetii.Peer Reviewe
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Ultrastructural damage of "loligo vulgaris" and "illex coindetii" Statocysts after low frequency sound exposure
'Public Library of Science (PLoS)', 2013Co-Authors: Solé Carbonell Marta, Lenoir Marc, Durfort Mercè, López Bejar Manel, Lombarte Carrera Antonio, André MichelAbstract:There is a considerable lack of information concerning marine invertebrate sensitivity to sound exposure. However, recent findings on cuttlefish and octopi showed that exposure to artificial noise had a direct consequence on the functionality and physiology of the Statocysts, sensory organs, which are responsible for their equilibrium and movements in the water column. Owing to a lack of available data on deep diving cephalopod species, we conducted a noise exposure comparative experiment on one Mediterranean squid, Illex coindetii, and on the European squid Loligo vulgaris. Scanning electron microscopy (SEM) revealed similar injuries in the inner structure of the Statocysts, as those found in cuttlefish and octopi. In addition to the ultrastructural description of the lesions, we publish here the first images of the crista-cupula system and inner Statocyst cavity of I. coindetii.Peer ReviewedPostprint (published version
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Ultrastructural Damage of Loligo vulgaris and Illex coindetii Statocysts after Low Frequency Sound Exposure
'Public Library of Science (PLoS)', 2013Co-Authors: Solé Marc, Lenoir Marc, Durfort Mercè, López Bejar Manel, Lombarte Antoni, André MichelAbstract:12 pages, 7 figuresThere is a considerable lack of information concerning marine invertebrate sensitivity to sound exposure. However, recent findings on cuttlefish and octopi showed that exposure to artificial noise had a direct consequence on the functionality and physiology of the Statocysts, sensory organs, which are responsible for their equilibrium and movements in the water column. Owing to a lack of available data on deep diving cephalopod species, we conducted a noise exposure comparative experiment on one Mediterranean squid, Illex coindetii, and on the European squid Loligo vulgaris. Scanning electron microscopy (SEM) revealed similar injuries in the inner structure of the Statocysts, as those found in cuttlefish and octopi. In addition to the ultrastructural description of the lesions, we publish here the first images of the crista-cupula system and inner Statocyst cavity of I. coindetiiThe Spanish Ministry of the Environment kindly funded this work (contract 083/SDGTB/2007). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscriptPeer reviewe
Michael L. Wiederhold - One of the best experts on this subject based on the ideXlab platform.
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Development of the Statocyst in Aplysia Californica
2005Co-Authors: Michael L. Wiederhold, Jyotsna S. Sharma, Jeffrey L. Harrison, Brian P. DriscollAbstract:The gravity receptor organs of gastropod molluscs, such as Aplysia californica, are bilateral paired Statocysts, which contain dense statoconia within a fluid-filled cyst. Gravitational forces on the statoconia are sensed through their interaction with ciliated mechanoreceptor cells in the wall of the cyst. Larval Aplysia contain a single statolith within each Statocyst; when the animals grow to a critical size, they begin producing multiple statoconia, a process that continues throughout life. The number of statoconia is highly correlated with animal weight but poorly correlated with age, indicating that stone production is related to total metabolism. The single statolith has an amorphous internal structure whereas the multiple statoconia have calcification deposited on concentric layers of membrane or matrix protein. The statolith appears to be produced within the cyst lumen but the multiple statoconia are produced within supporting cells between the receptor cells. Large adult animals have statoconia larger than those in early post-metamorphic animals which have just started producing multiple stones. The maximum Statocyst diameter at which the receptor-cell cilia can suspend the statolith in the center of the cyst lumen is 45 micrometers; production of multiple stones begins when the cyst reaches this size. The mechanisms by which statoconia production is initiated and controlled are discussed.
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Development of the Statocyst in the freshwater snail Biomphalaria glabrata (Pulmonata, Basommatophora)
Hearing research, 1997Co-Authors: Wenyuan Gao, Michael L. Wiederhold, Robert HejlAbstract:The development of the Statocyst of the freshwater snail Biomphalaria glabrata has been examined from embryo to adult. Special emphasis was put on the growth of the statoconia in the Statocysts. In the Statocysts of embryonic snails (90-120 h after oviposition) there is not a single statolith but an average of 40-50 statoconia per Statocyst. The number of statoconia increases to 385-400 when the snails reach a shell diameter of 4 mm and remains relatively constant thereafter, irrespective of shell size. Small statoconia are found in supporting cells, which suggests that the statoconia are produced within these cells. The average diameter of statoconia and the total mass of statoconia increase with increasing shell diameter. The average number of large statoconia (diameter > 7 microm) per Statocyst continues to increase from 2 to 10 mm animals while the number of small ones (diameter < 4 microm) initially rises and then decreases after 4 mm. These results demonstrate continuous growth of the statoconia in the cyst lumen of Biomphalaria. The single statoconia vibrate in a regular pattern in vivo, indicating beating of the Statocyst cilia. The statoconia sink under the influence of gravity to load and stimulate receptor cells which are at the bottom. The length of cilia and the size of Statocyst gradually increase as the animal grows. However, the increase in the volume of the Statocyst is relatively small compared with the increase in body weight during normal development.
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The Structure of the Statocyst of the Freshwater Snail Biomphalaria Glabrata (Pulmonata, Basommatophora)
Hearing research, 1997Co-Authors: Wenyuan Gao, Michael L. WiederholdAbstract:The structure of the Statocyst of the freshwater snail Biomphalaria glabrata has been examined by light and electron microscopy. The two Statocysts are located on the dorsal-lateral side of the left and right pedal ganglion. The Statocysts are spherical, fluid-filled capsules with a diameter of approximately 60 microm for young and 110 microm for adult snails. The wall of the cyst is composed of large receptor cells and many smaller supporting cells. The receptor cells bear cilia which are evenly distributed on the apical surface. The cilia have the typical 9+2 internal tubule configuration. Striate rootlets originate from the base of the basal body and run downward into the cytoplasm. Side-roots arise from one side of the basal body and a basal foot from the other. For each receptor cell, the basal foot always points to the periphery of the surface, indicating that the receptor cell is non-polarized. The receptor cells contain cytoplasmic organelles such as mitochondria, ribosomes, rough and smooth endoplasmic reticulum, compact Golgi bodies and multivesicular bodies. Supporting cells bearing microvilli are interposed between the receptor cells. The junction complex between the supporting cells and the receptor cells is composed of adherens and septate junctions, while between supporting cells only the adherens junctions are present. The static nerve arises from the lateral side of the cyst and contains axons in which parallel neurotubules and mitochondria are found. The axons arise directly from the base of the receptor cells without synapse. In the cyst lumen there are unattached statoconia. The statoconia have a plate-like or concentric membranous ring structure. Based on the morphology, the function of the Statocyst in Biomphalaria is discussed.
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Regulation of Statoconia Mineralization in Aplysia californica In Vitro
Connective tissue research, 1996Co-Authors: H A Pedrozo, Zvi Schwartz, David D Dean, Michael L. Wiederhold, B D BoyanAbstract:Statoconia are calcium carbonate inclusions in the lumen of the gravity-sensing organ, the Statocyst, of Aplysia californica. The aim of the present study was to examine the role of carbonic anhydrase and urease in statoconia mineralization in vitro. The experiments were performed using a previously described culture system (Pedrozo et al., J. Comp. Physiol. (A) 177:415-425). Inhibition of carbonic anhydrase by acetazolamide decreased statoconia production and volume, while inhibition of urease by acetohydroxamic acid reduced total statoconia number, but had no affect on statoconia volume. Inhibition of carbonic anhydrase initially increased and then decreased the Statocyst pH, whereas inhibition of urease decreased Statocyst pH at all times examined; simultaneous addition of both inhibitors also decreased pH. These effects were dose and time dependent. The results show that carbonic anhydrase and urease are required for statoconia formation and homeostasis, and for regulation of Statocyst pH. This suggests that these two enzymes regulate mineralization at least partially through regulation of Statocyst pH.
Marta Solé - One of the best experts on this subject based on the ideXlab platform.
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Ultrastructural damage of Loligo vulgaris and Illex coindetii Statocysts after low frequency sound exposure.
PloS one, 2013Co-Authors: Marta Solé, Marc Lenoir, Mercè Durfort, Manel López-bejar, Antoni Lombarte, Michel AndréAbstract:There is a considerable lack of information concerning marine invertebrate sensitivity to sound exposure. However, recent findings on cuttlefish and octopi showed that exposure to artificial noise had a direct consequence on the functionality and physiology of the Statocysts, sensory organs, which are responsible for their equilibrium and movements in the water column. Owing to a lack of available data on deep diving cephalopod species, we conducted a noise exposure comparative experiment on one Mediterranean squid, Illex coindetii, and on the European squid Loligo vulgaris. Scanning electron microscopy (SEM) revealed similar injuries in the inner structure of the Statocysts, as those found in cuttlefish and octopi. In addition to the ultrastructural description of the lesions, we publish here the first images of the crista-cupula system and inner Statocyst cavity of I. coindetii.
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RMI (A) and LM (B-D).
2013Co-Authors: Marta Solé, Marc Lenoir, Mercè Durfort, Manel López-bejar, Antoni Lombarte, Michel AndréAbstract:Decapods Statocyst location in the cephalic cartilage. A: Coronal view –anterior section- of squid (L. vulgaris) head. B, C: Photomicrograps of decapod Statocyst structure. Upper view in the opened Loligo vulgaris Statocyst. B shows the statocyt attached to the macula statica princeps and a statoconia attached to the superior macula neglecta. In C the Statocyst was removed and the macula statica princeps is visible. D: L. vulgaris statolith. (B: Brain, cc: cranial cartilage, e: eye, es: oesophagus, m: mouth, psg: posteror salivary gland, st: Statocyst. ST: Statolith. Sc: statoconia. M: Macula statica princeps). Scale bars: A = 2 cm. B, C = 2 mm. D =1 mm.