Planarian Dugesia Tigrina Research Articles

Lubricants reduce fission of the planarian flatworm (Dugesia tigrina) (Girard)

Vaseline petroleum jelly applied to the substrate was found to be the most effective of five lubricants tested in reducing asexual reproduction (fission) in the planarian flatworm Dugesia tigrina (Girard). Planarians which did not bud attained a much greater size than untreated controls.

Fine structural observations on the protonephridium of the terrestrial triclad Geoplana pasipha.

The protonephridial system of the terrestrial triclad Geoplana pasipha was studied by electron microscopy. In general construction it conforms to that of the freshwater planarian Dugesia tigrina (McKanna, 1968, 1968a). Ultrastructural details permit the identification of proximal, collecting, osmoregulatory and nephridiopore regions. Intralumenal material is frequently observed within the tubules, whose cells are always joined by septate junctions. Cilia are numerous and possibly contribute to the flow of water and solutes along the system. Proximal tubules have a peculiar, particulate membrane coat, while a continuous coat, densely stainable with ruthenium red lines the more distal, unciliated tubules.

Scanning electron microscopical observations on epidermal wound healing in the PlanarianDugesia tigrina.

Epidermal wound healing in regeneratingDugesia tigrina (Planaria) has been studied using scanning electron microscopy (SEM). The normal epidermal surface and its differentiations have been descrebed. Observations on living material reveal the highly dynamic state of the wound in invididual animals and its more or less continously changing size due to the state of activity of the animals. These observations show good agreement with the SEM studies, which allow a clear delineation of cellular details of the wound, the wound margins and the apposing epidermal regions. These details are described. The over-all picture of planarian wound healing that emerges is briefly as follows: Epithelization is characterized by absence of proliferation from the "old" intact epidermis. Variable contraction of smooth muscle cells reduces the wound size to a certain extent. Simultaneously with this and also during a longer period epidermal cells adjacent to the wound are extending and some become highly attenuated. These two processes together are only to a certain degree effective in wound closure because of a definite epidermal cell deficit which is reflected in the emergence of an epidermal wound edge reflecting the maximal contribution of these two processes to an attempt to close the wound. Complete epithelization is effected by the operation of a third mechanism: Recruitment of cell through flow of subjacent "blastemal cells" (including rhabdite-forming cells) along the wound border; these cells subsequently occupy a peripheral position in the wound. This process is supplemented by cell immigration and insertion into the adjacent old epidermis and in the wound cell sheet. Rhabdite-forming cells contribute predominantly to this process. Eventually integration between old epidermal cells and the newly recruited cells which differentiate into epidermal cells results in final epithelization. Complete wound healing is based on interactions between the epidermal cell system and the regenerating subepidermal membrane-connective tissue filament-muscle cell system.

Morphological stages of regeneration in the planarian Dugesia tigrina: A light and electron microscopic study.

A precise sequence of four morphological stages of head regeneration in the planarian Dugesia tigrina has been determined by light and electron microscopy. Each stage is identified by a particular morphogenetic process: I, wound healing; II, blastema development; III, growth; IV, differentiation. A wound epidermis consisting of a thin, sheet-like layer of cells, rapidly forms from undamaged epidermal cells at the wound margin. The early blastema is comprised of neoblasts which mature into regeneration cells. The maturational changes include the appearance of a nucleolus, nuclear pores, and perinuclear dense aggregates of granulofibrillar material in these cells. These elements are not evident in the neoblasts of the younger blastema. No mitotic cells are encountered in the blastema or wound epidermis. Cytoplasmic expansion of the regeneration cells is correlated with the formation of numerous microtubules radiating from a juxtanuclear centrosphere. During differentiation of muscle cells, distended, granule-studded cisternae, having moderately fibrillar contents, are regularly disposed adjacent to small patches of myofilaments. Presumptive epidermal cells are recognized by prominent "islands" of finely fibrillar cytoplasm. These cytoplasmic zones persist for a time during definitive differentiation when Golgi bodies, vacuoles, mucous droplets, and rhabdites become evident. The newly formed epidermal cells become inserted among the cells of the wound epidermis. Thus, cells of both the blastema and of the wound epidermis contribute to the reconstituted epidermis.

Studies on regeneration blastemas of the planarianDugesia tigrina with special reference to differentiation of the muscle-connective tissue filament system

Head blastemas in regeneratingDugesia tigrina (Planaria) have been studied light microscopically and electron microscopically. Acid phosphatase activity has been followed in early blastemas using a light microscopical cytochemical method. The possibilities of a collagen synthesis inhibiting substance α-α'-dipyridyl in analyzing fibrillogenesis in planarians have been explored.Following a brief discussion of the neoblast concept the general organization and characteristics of the blastema are described. Regeneration of the muscle-connective tissue filament system including the subepidermal membrane is analyzed in detail. It is stressed that the muscle cells, the filamentous sheaths and the subepidermal membrane in planarians should be visualized as a mutually dependent, integrated system. The hypothesis is proposed that neoblasts differentiate into myoblasts which both synthesize myofilaments and collagen. Collagen forms the filaments of the subepidermal membrane-muscle sheath system. No certain interference with collagen synthesis and secretion could be demonstrated in the experiments involving α-α'-dipyridyl.There was no evidence for significant changes in the activity and pattern of acid phosphatase during early stages of regeneration.The problems concerning the existence of neoblasts, their participation in regeneration and their origin (stock cell or result of a dedifferentiation process) are discussed.

The Diet of the Immigrant Planarian Dugesia tigrina (Girard): II. Food in the Wild and Comparison with Some British Species

The Diet of the Immigrant Planarian Dugesia tigrina (Girard): II. Food in the Wild and Comparison with Some British Species

Protection by Serotonin-Creatinine Sulfate Complex of the Planaria Dugesia tigrina Against the Lethal Effects of X-Rays

The serotonin-creatinine sulfate complex (S-CS) at a concentration of 3.14 × 10−5 M protected the planarian Dugesia tigrina from the lethal action of X-rays; the dose reduction factor was 1.88. Vasoconstriction and the subsequent lowering of oxygen tension inside the tissues was not involved in this observed radioprotection.

Observations on the fine structure of photoreceptor cells in the planarian Dugesia tigrina

The bipolar photoreceptor cell of the planarian Dugesia tigrina was studied by electron microscopy. The photosensitive structure within the pigment-enclosed eyecup is attached to the free end of a cell process. This process, the dendritic fiber, contains large vesicles, mitochondria, and numerous neurotubules. It leads into an expanded cell body located lateral to and outside of the opening of the eyecup. The cell body contains a nucleus, nucleolus, mitochondria, several Golgi complexes, multivesicular bodies, vacuoles, free ribosomes, and ribosomes associated with an extensive endoplasmic reticulum longitudinally oriented in the cell. The axon, containing vesicles and few neurotubules, extends to the cerebral ganglion and ends in a terminal axonal enlargement which may contain mitochondria, numerous synaptic vesicles, and glycogen granules.

OBSERVATIONS ON THE FINE STRUCTURE OF PHARYNGEAL MUSCLE IN THE PLANARIAN DUGESIA TIGRINA.

Pharyngeal muscle of the planarian Dugesia tigrina was studied by electron microscopy after osmium tetroxide fixation. The muscle cell was observed to contain one myofibril or bundle of myofilaments parallel to its longitudinal axis. The myofilaments were of two types, different in size and distribution. No Z lines or myofilament organization into cross or helical striations were seen. Dense bodies were seen as projections from an invagination of the plasma membrane and as dense lines parallel to the myofilaments. The muscle cells are surrounded by a plasma membrane which is structurally associated with dense body projections, with vesicles and cisternae of sarcoplasmic reticulum, and with synaptic nerve endings. The cell has sarcoplasmic projections perpendicular to its long axis; these projections are seen to contain the nucleus or mitochondria and granules. Mitochondria and granules are also seen in a sarcoplasm rim around the fibril. The dense bodies may serve as attachment for thin myofilaments and function in transmission of stimuli from plasma membrane to the interior of the fibril.

Carbon Dioxide Fixation in Marine Invertebrates: III. THE MAIN PATHWAY IN FLATWORMS

primarily in succinic, fumaric, and malic acids, suggested that most animals share the main pathway demonstrated in the oyster (2), namely, the carboxylation of propionate to form succinate, which is then metabolized through the citric acid cycle. The flatworms, Stylochus zebra and Bdelloura candida, however, had relatively little Cl4 in succinic acid and a large amount in an acid not identifiable with those of the cycle (1). The purpose of the experiments described in this report was to determine the principal pathways of COz fixation in free-living flatworms. The common fresh-water planarian Dugesia tigrina, the two marine turbellarians of the previous study, and a trematode Entobdella bumpusi were found to exhibit very similar patterns of labeling of organic acids after incubation for various periods in water containing NaHC1403. These flatworms form a series of increasing closeness of association with larger animals, from Dugesia, which has no association, to Stylochus, which inhabits the same shell as hermit crabs, to Bdelloura, which attaches to the legs and gills of the horseshoe crab. The monogenetic trematode E. bump& is an ectoparasite of the sting ray. The general results indicated that, although propionate is utilized by flatworms, the principal carboxylation in the absence of added substrate is the conversion of pyruvate to malate.

Regeneration and Regulation of Multiple-Headed Forms in the Planarians Dugesia tigrina Girard and Dugesia agilis Stringer

Regeneration and Regulation of Multiple-Headed Forms in the Planarians Dugesia tigrina Girard and Dugesia agilis Stringer

The Head Frequency Gradient in Euplanaria dorotocephala

Previous articleNext article No AccessThe Head Frequency Gradient in Euplanaria dorotocephalaC. M. Child and Y. WatanabeC. M. Child Search for more articles by this author and Y. Watanabe Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by Volume 8, Number 1Jan., 1935 Article DOIhttps://doi.org/10.1086/physzool.8.1.30151240 Views: 3Total views on this site Citations: 19Citations are reported from Crossref Journal History This article was published in Physiological Zoology (1928-1998), which is continued by Physiological and Biochemical Zoology (1999-present). PDF download Crossref reports the following articles citing this article:Sarah A. Elliott, Alejandro Sánchez Alvarado The history and enduring contributions of planarians to the study of animal regeneration, Wiley Interdisciplinary Reviews: Developmental Biology 2, no.33 (Jul 2012): 301–326.https://doi.org/10.1002/wdev.82Peter W. Reddien, Alejandro Sánchez Alvarado FUNDAMENTALS OF PLANARIAN REGENERATION, Annual Review of Cell and Developmental Biology 20, no.11 (Nov 2004): 725–757.https://doi.org/10.1146/annurev.cellbio.20.010403.095114Robert W. Mead Effect of timing of cutting on patterning and proportion regulation during regeneration of the planarian Dugesia tigrina, Hydrobiologia 227, no.11 (Dec 1991): 25–30.https://doi.org/10.1007/BF00027577Robert W. Mead Proportioning of body regions in the planarianDugesia tigrina as a function of the length: Width ratio of the regenerating fragment, Journal of Experimental Zoology 259, no.11 (Jul 1991): 69–77.https://doi.org/10.1002/jez.1402590110Robert W. Mead Effect of timing of cutting on patterning and proportion regulation during regeneration of the planarian Dugesia tigrina, (Jan 1991): 25–30.https://doi.org/10.1007/978-94-011-2775-2_4Robert W. Mead, Martha A. Krump Abnormal regeneration in the planarianDugesia tigrina as a function of the length: Width ratio of the regenerating fragment, Journal of Experimental Zoology 239, no.33 (Sep 1986): 355–364.https://doi.org/10.1002/jez.1402390307Robert W. Mead Proportioning and regeneration in fissioned and unfissioned individuals of the planarianDugesia tigrina, Journal of Experimental Zoology 235, no.11 (Jul 1985): 45–54.https://doi.org/10.1002/jez.1402350107CHRISTOPHER S. LANGE, VERNON E. STEELE The Mechanism of Anterior-Posterior Polarity Control in Planarians, Differentiation 11, no.1-31-3 (Sep 1978): 1–12.https://doi.org/10.1111/j.1432-0436.1978.tb00965.x REFERENCES, (Jan 1969): 235–261.https://doi.org/10.1016/B978-0-08-012876-4.50029-2S.Meryl Rose Polarized control of regional structure in Tubularia, Developmental Biology 7 (Jan 1963): 488–501.https://doi.org/10.1016/0012-1606(63)90137-4S. MERYL ROSE ULAR INTERACTION DURING DIFFERENTIATION, Biological Reviews 32, no.44 (Nov 1957): 351–382.https://doi.org/10.1111/j.1469-185X.1957.tb00776.xS. Meryl Rose SPECIFIC INHIBITION DURING DIFFERENTIATION, Annals of the New York Academy of Sciences 60, no.77 (Jun 1955): 1136–1159.https://doi.org/10.1111/j.1749-6632.1955.tb40093.xH. V. BRØNDSTED PLANARIAN REGENERATION, Biological Reviews 30, no.11 (Feb 1955): 65–126.https://doi.org/10.1111/j.1469-185X.1955.tb00649.xMartin Lüscher Die Regeneration in der Zoologie, (Jan 1955): 405–440.https://doi.org/10.1007/978-3-642-94649-3_7Yisamu Watanabe Physiological studies on a fresh water triclad, Polycelis sapporo. I. Character and rate of reconstitution of transverse pieces in relation to level of body, Journal of Experimental Zoology 109, no.22 (Nov 1948): 291–329.https://doi.org/10.1002/jez.1401090210J. Walter Wilson The regeneration of the planarian head in diluted Ringer's fluid, Journal of Experimental Zoology 86, no.22 (Mar 1941): 225–245.https://doi.org/10.1002/jez.1400860206 Floyd J. Wiercinski The Effects of Supersonic Vibrations on Reconstitution and Head Frequency in Euplanaria dorotocephala, Physiological Zoology 12, no.11 (Sep 2015): 62–69.https://doi.org/10.1086/physzool.12.1.30151480H. V. Brøndsted Experiments with methylene blue on the reducing capacity of Dendrocoelum lacteum, Protoplasma 27, no.11 (Dec 1937): 556–562.https://doi.org/10.1007/BF01599438 Y. Watanabe Rate of Head Development as Indicated by Time of Appearance of Eyes in the Reconstitution of Euplanaria dorotocephala, Physiological Zoology 8, no.11 (Sep 2015): 41–64.https://doi.org/10.1086/physzool.8.1.30151241