Proteomic analysis of body wall and coelomic fluid in Sipunculus nudus

2021 ◽  
Vol 111 ◽  
pp. 16-24
Author(s):  
Yupo Cao ◽  
Xuli Lu ◽  
Yaping Dai ◽  
Yahui Li ◽  
Fei Liu ◽  
...  
1997 ◽  
Vol 272 (1) ◽  
pp. R350-R356 ◽  
Author(s):  
A. Reipschlager ◽  
G. E. Nilsson ◽  
H. O. Portner

Involvement of neurotransmitters in metabolic depression under hypoxia and hypercapnia was examined in Sipunculus nudus. Concentration changes of several putative neurotransmitters in nervous tissue during anoxic or hypercapnic exposure or during combined anoxia and hypercapnia were determined. Among amino acids (gamma-aminobutyric acid, glutamate, glycine, taurine, serine, and aspartate) and monoamines (serotonin, dopamine, and norepinephrine), some changes were significant, but none were consistent with metabolic depression under all experimental conditions applied. Only the neuromodulator adenosine displayed concentration changes in accordance with metabolic depression under all experimental conditions. Levels increased during anoxia, during hypercapnia, and to an even greater extent during anoxic hypercapnia. Adenosine infusions into coelomic fluid via an indwelling catheter induced a significant depression of the normocapnic rate of O2 consumption from 0.36 +/- 0.04 to a minimum of 0.24 +/- 0.02 (SE) mumol.g-1.h-1 after 90 min (n = 6). Application of the adenosine antagonist theophylline caused a transient rise in O2 consumption 30 min after infusion during hypercapnia but not during normocapnia. Effects of adenosine and theophylline were observed in intact individuals but not in isolated body wall musculature. The results provide evidence for a role of adenosine in inducing metabolic depression in S. nudus, probably through the established effects of decreasing neuronal excitability and neurotransmitter release. In consideration of our previous finding that metabolic depression in isolated body wall musculature was elicited by extracellular acidosis, it is concluded that central and cellular mechanisms combine to contribute to the overall reduction in metabolic rate in S. nudus.


1960 ◽  
Vol s3-101 (54) ◽  
pp. 149-176
Author(s):  
R. B. CLARK ◽  
M. E. CLARK

Nephtys lacks circular body-wall muscles. The chief antagonists of the longitudinal muscles are the dorso-ventral muscles of the intersegmental body-wall. The worm is restrained from widening when either set of muscles contracts by the combined influence of the ligaments, some of the extrinsic parapodial muscles, and possibly, to a limited extent, by the septal muscles. Although the septa are incomplete, they can and do form a barrier to the transmission of coelomic fluid from one segment to the next under certain conditions, particularly during eversion of the proboscis. Swimming is by undulatory movements of the body but the distal part of the parapodia execute a power-stroke produced chiefly by the contraction of the acicular muscles. It is suspected that the extrinsic parapodial muscles, all of which are inserted in the proximal half of the parapodium, serve to anchor the parapodial wall at the insertion of the acicular muscles and help to provide a rigid point of insertion for them. Burrowing is a cyclical process involving the violent eversion of the proboscis which makes a cavity in the sand. The worm is prevented from slipping backwards by the grip the widest segments have on the sides of the burrow. The proboscis is retracted and the worm crawls forward into the cavity it has made. The cycle is then repeated. Nephtys possesses a unique system of elastic ligaments of unusual structure. The anatomy of the system is described. The function of the ligaments appears to be to restrain the body-wall and parapodia from unnecessary and disadvantageous dilatations during changes of body-shape, and to serve as shock-absorbers against the high, transient, fluid pressures in the coelom, which are thought to accompany the impact of the proboscis against the sand when the worm is burrowing. From what is known of its habits, Nephtys is likely to undertake more burrowing than most other polychaetes.


2002 ◽  
Vol 31 ◽  
Author(s):  
DENILTON VIDOLIN ◽  
IVONETE A. SANTOS GOUVEA ◽  
CAROLINA A. FREIRE

Animais de entre-marés podem ser expostos ao ar durante a maré baixa, por pelo menos 1-2 horas. Os animais expostos ao ar são susceptíveis a perda de sal e/ou entrada de água durante chuva intensa, ou perda de água pela ação de dessecação do sol. A osmolalidade de amostras de fluido celômico obtidas do pepino-do-mar Holothuria grisea e da estrela-do-mar Asterina stellifera expostas ao ar, ou de animais controles imersos na água do mar adjacente foi determinada. As amostras foram obtidas imediatamente após a exposição ao ar, e novamente após uma hora de exposição ao ar, durante a maré baixa no campo, em tempo nublado, chuvoso, ou ensolarado, na Praia rochosa do Quilombo, Penha, Sul do Brasil. Uma hora de exposição a qualquer das condições climáticas indicadas não alterou a osmolalidade dos fluidos celômicos. Houve pequena redução nas osmolalidades dos fluidos celômicos durante a exposição ao ar com precipitação de chuva. Sugere-se que estes equinodermas possam imediatamente detectar sua exposição ao ar, e possam então reduzir a permeabilidade osmótica de sua parede do corpo, para evitar perda de água para o ar ou entrada de água/saída de sal durante a chuva. ABSTRACT Intertidal animals can be exposed to the air during low tide, for at least 1-2 hours. Animals exposed to the air are subject to salt loss (or water gain) from heavy rains or volume loss from the desiccating action of the sun. Coelomic fluid samples obtained from the sea-cucumber Holothuria grisea and the starfish Asterina stellifera exposed to the air or from control animals submerged in surrounding sea water have been assayed for osmolality. Samples were obtained right after air exposure and again after 1 hour of exposure to the air during low tide in the field, either under cloudy, rainy or sunny weather conditions, in the rocky beach of Quilombo, Penha, Southern Brazil. One hour of exposure to any of the conditions did not change coelomic fluid osmolalities. There was a slight reduction in coelomic fluid osmolalities upon air exposure during rainfall. It is suggested that these echinoderms can somehow immediately detect air exposure and reduce their body wall permeability to avoid water loss or water influx/salt loss during rainfall. RÉSUMÉ Animaux d’entre-marées peuvent êtres exposés a l’air libre pendant le reflux de la marée, pour environ une ou deux heures seulement. Ces animaux, quand exposés a l’air libre, sont susceptibles de perdre du sel et d’absorber de l’eau pendant une période de pluie intense. Par contre, ils peuvent perdre de l’eau si soumis a l’action de dessèchement due a une éxposition au soleil. On a réussi a determiner l’osmolalité d’échantillons du fluide celomique obtenus du Pépin-de-mer Holothuria grisea et de l’Étoile-de-mer Asterina stellifera exposés a l’air libre, e d’animaux-controles immergés dans l’eau de mer voisin. Les échantillons ont été obtenus tout de suite après l’exposition à l’air et, une seconde fois, après une heure d’exposition à l’air libre, pendant la durée de la marée basse, soit sous la pluie, soit au soleil ou soit sous un ciel ombrageux, à la plage rocailleuse de Quilombo, Penha, au sud du Brésil. Une heure d’éxposition à n’importe quelles conditions climatiques indiquées, n’ont pas pu altérer l’osmolalité des fluides celomiques, ce que sugère la conclusion que ces échinodermes peuvent détecter immédiatement sa exposition à l’air libre et peuvent tout de suite réduire la permeabilité osmotique de la membrane que recouvre son corps pour éviter perdre d’eau et, de la même façon, reduire l’absortion de l’eau pendant la pluie. On a observé une petite réduction de fluides celomiques pendant l’exposition a l’air, avec ocurrence de pluie.


Author(s):  
Norman Millott

The black body-wall pigment of Holothuria forskali shows the characteristics of melanin.From histological evidence it appears that the pigment is formed in association with the amoebocytes of the coelomic fluid, which eliminate the pigment in the body wall.The amoebocytes contain a phenolase system, distinct from the cytochromecytochrome oxidase system, with the properties of tyrosinase.The relation of these findings to those of a preceding and more complete investigation into melanogenesis in Diadema is discussed.


1999 ◽  
Vol 202 (7) ◽  
pp. 855-866 ◽  
Author(s):  
K. Hauschild ◽  
W.M. Weber ◽  
W. Clauss ◽  
M.K. Grieshaber

Thiosulphate, the main sulphide detoxification product, is accumulated in the body fluids of the lugworm Arenicola marina. The aim of this study was to elucidate the fate of thiosulphate. Electrophysiological measurements revealed that the transepithelial resistance of body wall sections was 76+/−34 capomega cm2 (mean +/− s.d., N=14), indicating that the body wall of the lugworm is a leaky tissue in which mainly paracellular transport along cell junctions takes place. The body wall was equally permeable from both sides to thiosulphate, the permeability coefficient of which was 1. 31×10(−)3+/−0.37×10(−)3 cm h-1 (mean +/− s.d., N=30). No evidence was found for a significant contribution of the gills or the nephridia to thiosulphate permeation. Thiosulphate flux followed the concentration gradient, showing a linear correlation (r=0.997) between permeated and supplied (10–100 mmol l-1) thiosulphate. The permeability of thiosulphate was not sensitive to the presence of various metabolic inhibitors, implicating a permeation process independent of membrane proteins and showing that the lugworm does not need to use energy to dispose of the sulphide detoxification product. The present data suggest a passive permeation of thiosulphate across the body wall of A. marina. In live lugworms, thiosulphate levels in the coelomic fluid and body wall tissue decreased slowly and at similar rates during recovery from sulphide exposure. The decline in thiosulphate levels followed a decreasing double-exponential function. Thiosulphate was not further oxidized to sulphite or sulphate but was excreted into the sea water.


1945 ◽  
Vol s2-85 (340) ◽  
pp. 343-389
Author(s):  
KARM NARAYAN BAHL

1. In an earthworm, as in most aquatic invertebrates, urea and ammonia form the main bulk of nitrogenous excretion and there is no trace of uric acid. These excretory products are first formed in the body-wall and gut-wall, pass therefrom into the coelomic fluid and blood, and are thence eliminated to the exterior by the nephridia. In Pheretima urea and ammonia pass out from the nephridia to the exterior either directly through the skin or through the two ends of the gut. 2. Ammonia and urea have been estimated for the first time in the blood, coelomic fluid, and urine of the earthworm. It has been shown that blood is not a mere carrier of oxygen, as Rogers believed, but that it also takes part in carrying urea and ammonia from the body-wall and gut-wall to the nephridia. The blood of the earthworm does not coagulate, indicating absence of fibrinogen. 3. The role of the nephridia in excretion and osmotic regulation has been determined. A comparison of the osmotic pressures of blood, coelomic fluid, and urine shows that the coelomic fluid is hypotonic to the blood, and that urine is markedly hypotonic both to the blood and coelomic fluid. The protein and chloride contents of the blood, coelomic fluid, and urine have been determined with a view to elucidate the differences in their osmotic pressures. It has been found that the urine contains the merest trace of protein, but that the amount of proteins in the blood is about eight times that contained in the plasma of the coelomic fluid. On the contrary, the chloride content of the coelomic fluid-plasma is about 60 per cent, higher than that of the blood-plasma. 4. The part of urine which is excreted from the blood is probably a protein-free filtrate, but the nephridia reabsorb all the proteins passing into them with the coelomic fluid-plasma. Similarly, there is a reabsorption of chlorides on a large scale from the initial nephridial filtrate during its passage through the nephridia. 5. A convenient method has been devised for collecting urine of the earthworm, which has made it possible to collect as much as 25 c.c. of urine in two and a half hours. The rate of excretion of the urine has been determined and it has been found that in an earthworm living in water the outflow of urine in twenty-four hours must be more than 45 per cent, of its body-weight. 6. It seems that an earthworm, when submerged in water, can live like a fresh water animal, and its gut acts as an osmoregulatory organ in addition to the nephridia, but in the soil it lives like a terrestrial animal and the osmo-regulatory function is adequately discharged by the nephridia alone which reabsorb chlorides and proteins, and are also active in the conservation of water. In Pheretima and other earthworms with an enteronephric type of nephridial system, the gut takes a prominent part in reabsorbing the water of the nephridial fluid and conserving water to its maximum extent. 7. The phagocytic section (ciliated middle tube) believed by Schneider to be absent in the nephridia of Pheretima has been shown to be distinctly present; it is also present in the nephridia of Lampito , Eutyphoeus, and Tonoscolex. The brownish yellow granules characteristic of this phagocytic section form a heavy deposit in the septal nephridia of Pheretima posthuma, heavier than that described in Lumbricus. The deposit increases with the age of the earthworm and forms a ‘storage excretory product’. 8. Spectroscopic examination has revealed that these brownish yellow granules, so far believed to be of guanine, are really blood-pigment granules, since a pyridine solution of them shows the two characteristic bands of haemochromogen. With regard to the blood-pigment, the nephridia function as ‘storage kidneys’. 9. The mechanism of nephridial excretion of the earthworm can be analysed into processes of filtration, reabsorption, and chemical transformation. 10. It is probable that the dorsal and ventral phagocytic organs of earthworms are additional excretory organs.


This investigation is an attempt to obtain quantitative results on the method of functioning of the body-wall muscle-coelomic fluid system of the lugworm which was chosen as an example of a worm having this system in a relatively simple condition. Measurements of the hydrostatic pressure developed in the coelomic fluid during various phases of activity, particularly during burrowing, were recorded, and the mechanism by which pressure is differentially distributed throughout the body is discussed. The relation of pressure changes to burrowing movements is described and some calculations of the thrust which can be exerted by the worms are given. It is shown that the forces available to the worms are insufficient to allow of straight­-forward burrowing and that the ability to burrow depends on the thixotropic properties of the muddy sand in which the animals live.


1986 ◽  
Vol 122 (1) ◽  
pp. 51-64
Author(s):  
H. O. PÖRTNER ◽  
S. VOGELER ◽  
M. K. GRIESHABER

Intra- and extracellular acid-base status and changes of coelomic PCOCO2 were investigated during recovery following 24 h of anaerobiosis in Sipunculus nudus L. Metabolism, gas exchange and acid-base status were compared in animals collected during March and October. Anaerobiosis led to an uncompensated metabolic acidosis, the degree of the acidosis depending on the metabolic rate of the animals. During initial recovery in March animals, the acidosis was transiently aggravated in the extracellular, but not in the intracellular, compartment, indicating an efficient regulation of intracellular pH as soon as oxygen was available in the coelomic fluid. The extracellular acidosis was predominantly of non-respiratory origin. The non-respiratory part of the acidosis is attributed to the repletion of the phospho-l-arginine pool. The proton yield calculated from phosphagen resynthesis was highly correlated in time and in quantity to the observed negative base excess in the extracellular compartment. In October animals, strombine accumulation may have contributed to the acidosis that develops during recovery. The amount of succinate, propionate, and acetate in the coelomic plasma had already decreased when the acidosis developed. This discrepancy supports the conclusion that protons move between the body compartments independent of the distribution of anionic metabolites. The respiratory part of the acidosis is attributed to the repayment of an oxygen debt. The increase of PCOCO2 is higher in October than in March animals, probably because of differences in metabolic rate The time course of acid-base disturbances and their compensation is discussed in relation to the time course of metabolic events during recovery and to the priorities of the different processes observed.


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