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PubMed2006

Effect of GABAergic and adrenergic agents on activity of Na+/K+ pump and Cl(-)-cotransport in somatic muscle cells of earthworm Lumbricus Terrestris.

GABA, baclofen, epinephrine, and norepinephrine hyperpolarized the membrane of earthworm somatic cells. This effect was prevented by furosemide, removal of Cl- from the medium, or activation of Na+/K+ pump by 3-fold increase external potassium concentration. It was hypothesized that GABA, baclofen, epinephrine, and norepinephrine stimulate Na+/K+ transport via specific receptor inputs, but their effect on resting potential can be realized only under conditions of working Cl- symport.

Adrenergic Agents↗
PubMed1983

Dissociation and oxygen equilibrium properties of earthworm (Pheretima hilgendorfi) hemoglobin.

The dissociation and oxygen equilibrium properties of the purified hemoglobin and whole blood obtained from the earthworm Pheretima hilgendorfi were compared. Above pH 8.0, P1/2's were higher in the purified hemoglobin than in whole blood, while below pH 8.0, nearly identical P1/2's were observed in both materials and P1/2 was at a maximum at pH 6.5. The values of n1/2 were higher in whole blood than in the purified hemoglobin at alkaline pH. The maximum values of n1/2 were observed around pH 8.1 in the purified hemoglobin and pH 8.7 in whole blood, and the values were 5.3 and 9.5, respectively. In the purified hemoglobin, a small amount of dissociation component was already observed at pH 8.0, while in whole blood, no dissociation occurred up to pH 9.1. Dialysis of whole blood or addition of 10 mM EDTA to whole blood at alkaline pH induced the loss of the enhanced cooperativity, the increased oxygen affinity and the high stability of the 60 S whole molecule. These results strongly suggest that divalent cations are participating in the functional and dissociation properties of the whole blood of this species.

Animals↗
PubMed1995

Structural elucidation of two novel amphoteric glycosphingolipids from the earthworm, Pheretima hilgendorfi.

The novel amphoteric glycosphingolipids containing a choline phosphate were purified from whole tissues of the earthworm, Pheretima hilgendorfi. Their chemical structures were completely characterized as cholinephosphoryl-->6(Man alpha 1-4)Gal beta 1-6Gal beta 1-1Cer (cholinephosphorylmannosylneogalabiaosylceramide, named PGL3a) and cholinephosphoryl-->6Gal beta 1-6Gal beta 1-6Gal beta 1-1Cer (cholinephosphorylneogalatriaosylceramide, named PGL3b) by compositional sugar, fatty acid and sphingoid analyses, hydrogen fluoride degradation, partial acid hydrolysis, methylation analysis, exoglycosidase degradation, proton magnetic resonance spectroscopy and fast atom bombardment mass spectrometry. The ceramide moieties of these lipids consisted of 22:0, 23:0 and 24:0 acids as major fatty acids, and branched octadeca- and nonadeca-4-sphingenines and octadeca-4-sphingenine as main sphingoids. Since the oligosaccharides and the ceramide moieties of PGL3a and PGL3b were identical with those of neutral glycosphingolipids found in this organism, the biosynthesis of the amphoteric glycolipids may occur by the addition of a choline phosphate residue to the corresponding neutral glycolipids, Man alpha 1-4Gal beta 1-6Gal beta 1-1Cer or Gal beta 1-6Gal beta 1-6Gal beta 1-1Cer.

Animals↗
PubMed1978

Studies on erythrocruorin. VII. Reconstitution of earthworm erythrocruorin from the apoprotein.

Apoerythrocruorin prepared from the giant respiratory hemoprotein of the earthworm (60 S, Mr = 3 X 10(-6)) is an electrophoretically homogeneous molecule which sediments as a single peak of low molecular weight (3.5 S) and has a lower alpha-helical content (approx. 30%) than the native protein. Titration of globin with ferric heme indicates the presence of different binding sites; however, after purification by ion exchange chromatography, the reconstitution product contains 1 haem/23 000 g of protein as the native molecule. Reconstituted ferric erythrocruorin is a low molecular weight hemichrome with the same optical and physicochemical properties of the hemichrome formed by natural ferric erythrocruorin. Reconstituted ferrous erythrocruorin reacquires the alpha-helical content and the quaternary structure of the native molecule. Reassociation into 10-S speices (1/12 of the whole molecules) is fast and easy, while that into whole molecules is slow and somewhat erratic. The functional properties of reconstituted ferrous erythrocruorin (oxygen affinity, cooperativity in oxygen binding, magnitude of Bohr effect) are very similar to those of the "stable" low cooperativity form of the undissociated protein.

Apoproteins↗
PubMed1979

Earthworm (Pheretima communissima and Pheretima hilgendorfi) hemoglobins: giant assemblies and subunits.

The molecular architecture of hemoglobins and their subunits of the earthworms Pheretima communissima and Pheretima hilgendorfi was investigated. In both species, their s0.20,w of 60.8 S and D020,w of 1.80 . 10(-7) cm2 . s-1 corresponded to a molecular weight of 3.07 . 10(6). From electron microscopic observations, the overall structure of the hemoglobins was shown to be two superimposed hexagonal discs, each composed of six-membered constituents. Sodium dodecyl sulfate polyacrylamide gel electrophoresis of both hemoglobins revealed the presence of five species of subunits with molecular weights of 13,000-14,000 (subunit 1), 27,000-28,000 (subunit 2), 30,000-31,000 (subunit 3), 33,000-34,000 (subunit 4) and approx. 52,000 (subunit 5), respectively, and the molar ratio of these subunits 1:2, 3, 4:5 was 2:3:3. If we consider this set of the subunits 1 to 5 as one unit, the molecular weight of this unit should be 2.7-2.8 . 10(5). This one unit, therefore, should be considered to represent one-twelfth the whole molecule with molecular weight of 3.07 . 10(6).

Animals↗
PubMed1988

Fluorescence-histochemical and ultrastructural research on the monoaminergic neurosecretory cells of the earthworm Octolasium complanatum (Annelida: Oligochaeta).

A study of the yellow fluorescent neurons (M-NSC) of the subesophageal ganglion of the earthworm Octolasium complanatum has been made by using alternate semithin and thin sections in a correlate fluorescence and electron microscopy technique and it results that elementary neurosecretory granules are present where the yellow fluorescent substance is. These granules are similar in size and morphology to the granules of monoamine type. The intimate contact of the capillaries with the granular cytoplasmic area of the M-NSC provides evidence of a probable release of the secretion from the cell body. These results support the hypothesis of the endocrine role of the M-NSC.

Animals↗
PubMed1991

Immunohistochemical localization of endothelin-1 in the nervous system of the earthworm Eisenia foetida.

The distribution of a substance that resembles endothelin-1 (ET-1) was examined immunohistochemically in the nervous system of the earthworm, Eisenia foetida, using antiserum against ET-1. In the cerebral ganglion, ET-1-like immunoreactivity was demonstrated in two to three pairs of neurons located in the peripheral portion. These immunoreactive neurons projected axons toward the neuropile located in the central portion of the ganglion. Immunoreactive fibers were distributed in the neuropile and proceeded posteriorly to the subesophageal ganglion through the circumpharyngeal connective. In the subesophageal ganglion, no immunoreactive cell bodies were detected, although the immunoreactive fibers were found in the neuropile. In each segmental ganglion, two to eight immunoreactive neurons were observed on each side of the caudo-ventral portion and these neurons sent axons ipsilaterally to the fiber tracts. The pattern of distribution of the immunoreactive neurons in the segmental ganglion was almost identical from one segment to the next. No immunoreactivity was detected in the nerve tracts that emerge peripherally from the cerebral, subesophageal, and segmental ganglia or in other organs, such as the digestive tract and the integument. Specific immunoreactivity to antiserum raised against corticotropin-releasing factor (1-20) was not detected in the nervous system of Eisenia.

Animals↗
PubMed1981

Dorsal giant fibre septum of earthworm. Fine structural details and further evidence for gap junctions.

The fine structure of the dorsal giant fibre septa of earthworm (Lumbricus terrestris and Eisenia foetida) was studied by thin sectioning. E-PTA, BIUL and ZIO impregnation were carried out to characterize the various membrane specializations found. A septum, which is formed by two axon membranes only ca. 7 nm apart, is a heterogeneous structure showing a number of different specializations (intermediate junctions, dense projection-like humps, septate regions, vesicles quite often associated with a widened intercellular gap and membrane thickening). Septal areas referred to as septal complexes are of particular interest. They comprise up to 20% of septal cross-sections and are characterized by membrane appositions (diameter ca. 25 nm) which bridge the septal gap, protrude 16-25 nm into the respective axoplasms, and form a more or less hexagonal array with a centre-to-centre spacing of ca. 33 nm (ca. 29 nm after E-EPTA treatment) in en face sections. We interpret the septal complexes as gap junctions, i.e. sites of electronic coupling, and emphasize their unusually large dimension. The vesicles found at the septum could not be stained by ZIO treatment.

Animals↗
PubMed1983

Myelinating glia of earthworm giant axons: thermally induced intramembranous changes.

The median and lateral giant axons in the ventral nerve cord of the earthworm Lumbricus terrestris are ensheathed by extensive spiral glial cell wrappings which resemble vertebrate myelin. The other, smaller, axons are encompassed by attenuated glial processes, as is typical of invertebrates. The fine structural details of the glial cells have been studied in thin sections and in replicas produced by freeze-fracturing where the intramembranous particle (IMP) populations within the lipid bilayer are visible. These consist of both low-profile IMPs as well as prominent ones 6-8 nm in diameter, scattered at random over the lipid interface in the myelinating glia. The larger IMPs on both P and E faces number about 80/mum2 at 16 degrees C in contrast to the IMP density of 400/mum2 in the other glial membranes. After acclimation to 5, 16 and 26 degrees C, the loose myelin glial membranes show variations in the density of their larger IMP population; in animals acclimated over 3 or more weeks to 5 degrees C, the number of these IMPs is significantly (P less than 0.001) less per unit area than in animals acclimated to 16 or 26 degrees C. The size of the particles at 5 degrees C is significantly (P less than 0.001) smaller than those at 16 or 26 degrees C. When animals are subjected to a sudden differential in ambient temperature, from 26 or 16 to 5 degrees C, or from 5 to 26 degrees C, and their giant axons with encompassing glia are fixed and frozen 30 min after this temperature change, the IMP population of the glial membranes remaining does not appear to alter. The differences in the IMP population of the myelinating glial membranes at different temperatures may reflect the extent to which they insulate and/or influence the velocity of impulse propagation.

Acclimatization↗
PubMed1988

In vitro agglutinin production by earthworm leukocytes.

Leukocytes of the earthworm, Lumbricus terrestris, secrete agglutinins in vitro, as shown by measuring agglutinin titers of the culture medium and by observing secretory rosette formation by leukocytes with erythrocytes. Leukocytes form the highest percentages of secretory rosettes with rabbit erythrocytes (RBC) and with other RBC species in the order: rat, guinea pig, mouse, calf, sheep, horse, goat. Leukocytes displayed allotypic specificity by forming rosettes selectively with erythrocytes from different individual rabbits. Eight sugars inhibited rosette formation, along with the polysaccharide mannan and the glycoproteins thyroglobulin and bovine submaxillary mucin. Cyclohexamide did not affect rosette formation, suggesting that agglutinins may be preformed and stored in leukocytes prior to secretion. Leukocytes also formed E-type rosettes with erythrocytes, but apparently utilized different receptors from those of secretory rosettes since they were not inhibited by the same sugars.

Agglutinins↗
PubMedDate not supplied

A new approach to in vitro studies of antigenic response in earthworms.

A method for in vitro cultivation of earthworm gut wall tissue explants is described. Tissue explants are able to respond to protein antigen by secretion of antigen-binding protein into the culture medium. Large irregular cells and round-shaped cells are released from tissue explants during the cultivation. This method represents an advantageous tool for in vitro studies providing the possibility of parallel assays from the same donor.

Animals↗
PubMed1984

A comparison of standardized methods for measuring the biological activity of pesticides to the earthworm, Lumbricus terrestris.

Standardized methods for determining LC and LD50 values to the earthworm were compared. An LC50 is most quickly determined by exposing the worms to an ethanolic dip for 30 min. LC50 values can also be determined by soil-incorporation, a route which simulates natural exposure, although mortality sufficient for the estimation of an LC50 is not generated until 7-14 days have elapsed. Injection into the hemocoel proved most efficacious for determining an LD50; topical application was vitiated by irritation by the compound and the solvent. The symptoms which result from exposure are distinct and dose responsive. When using a standardized procedure for assessing toxicity, these symptoms are useful in gauging nonlethal effects of the compound and in facilitating comparison of data.

Acetonitriles↗
PubMed1991

Reduction of hexavalent chromium by the earthworm Eisenia foetida (Savigny).

Several metabolic systems in Eisenia foetida competent to achieve an intracellular Cr(VI) reduction are described. Evidence that earthworms act as effective scavengers of hexavalent chromium from the environment is also provided. Results suggest that E. foetida may play an important role during occasional Cr(VI) pollution of soils.

Animals↗
PubMed1991

Cellular but not humoral antibacterial activity of earthworms is inhibited by Aroclor 1254.

Earthworms, Eisenia fetida andrei and Lumbricus terrestris, exposed to Aroclor 1254, followed by infestation with Aeromonas hydrophila, elicited two types of responses. First, in E. fetida, there was no change in the LD50 nor in the in vitro antibacterial growth capacity of cell-free coelomic fluid. Thus, Aroclor exerts no influence on antibacterial proteins nor on the chloragogue cells responsible for their release. Second, in L. terrestris, both a high LD50 value and no antibacterial activity indicate that A. hydrophila was not pathogenic. The 10(4) times higher sensitivity of exposed L. terrestris suggests that Aroclor inhibits leukocyte activity since E. fetida eliminates nonpathogenic bacteria by a cellular mechanism.

Aeromonas hydrophila↗
PubMed1991

Detection of antigen in the coelomocytes of the earthworm, Eisenia foetida (Annelida).

Earthworms, Eisenia foetida, are able to respond to antigenic stimulation by the formation of the antigen-binding molecules by coelomocytes--the effector cells of annelids' defence reactions. The ability to react with gold-labelled antigen was detected in agranular coelomocytes by electron microscopy. Furthermore, flow cytometry analysis used for quantitative evaluation of antigen binding showed significant increase of both antigen-binding cells and the amount of antigen bound per cell after stimulation. The antigen binding was inhibited by preincubation of cells with several similar proteins, although the most potent inhibitor was the immunizing antigen.

Animals↗
PubMed1992

Repeated antigenic challenge induces earthworm coelomocyte proliferation.

Annelids are able to protect themselves against foreign materials by natural and acquired cellular immunity. The aim of this study was to characterize the kinetic of antigen induced proliferation of earthworm coelomocytes. The proliferative activity of free coelomocytes of Eisenia foetida decreased after a second contact with the same antigen. Precursor cells in the mesenchymal lining of the coelomic cavity responded to stimulation immediately. These results indicate that for a successful triggering of the proliferative response of the free coelomocytes repeated contact with stimulating agents is needed.

Animals↗
PubMed1993

The fate of protein antigen in earthworms: study in vivo.

Parenteral administration of antigen induces in the earthworms Lumbricus terrestris and Eisenia foetida the formation of antigen-binding protein. Labelled antigen was efficiently digested in the coelomic fluids of both species since the total amount of radioactivity in the coelomic fluids decreased. Antigen internalized in the free coelomocytes of both species was present in a TCA-precipitable form, although the decline of total radioactivity was higher than in the coelomic fluid, indicating that the TCA-nonprecipitable fragments are rapidly released from coelomocytes into the coelomic fluid. Within the first 24 h after administration, labelled antigen was detected throughout all tissues except for the epidermis and cuticle, and after 4 days it was found in the chloragogenic tissue around the gut, dorsal vein and typhlosole.

Animals↗
PubMed1995

Identification of a cytolytic protein in the coelomic fluid of Eisenia foetida earthworms.

Total coelomic fluid of earthworms Eisenia foetida (Oligochaeta, Annelida) is capable of lysing different mammalian tumor cell lines. This cytolytic activity is different from tumor necrosis factor (TNF)-mediated lysis and is not due to proteolysis. Total coelomic fluid was subjected to ion-exchange chromatography separation and a fraction with prominent cytolytic activity was used to elicit monoclonal antibodies that were screened for their capacity to neutralize the cytolytic effect of total coelomic fluid. One of the prepared neutralizing IgG antibodies was used for the immunoaffinity purification of a cytolytic factor from total coelomic fluid. SDS-PAGE and Western blot analyses revealed a protein band with an apparent molecular weight of 42 kDa. This cytolytic protein (termed CCF-1 or coelomic cytolytic factor 1) can be adsorbed on the surface of opsonized particles and may be involved in opsonizing and hemolytic effects of coelomic fluid.

Animals↗