Summary
The ultrastructure of the auricles, the ostia, and the ventricle of L. asellus and T. marmorea is described. The heart wall consists of an epicardium, a basement membrane, and an inner loose myocardium. The epicardial cells of the auricle are podocytes. The exposed cell body and the branched processes show pedicles. Ventricular epicardium is flat and simple. The slender, unbranched, mononucleated muscle fibres have a peripheral nucleus located midway along the fibre. Mitochondria are peripherally located, leaving the center to longitudinally running thick and thin myofilaments. Dense bodies and attachment plaques make up the Z-material. Sarcomeres and myofibrils are absent, as are transverse tubules and intercalated disks. The sarcoplasmic reticulum consists of peripheral tubules and subsarcolemmal cisternae, some of which radiate, branch, and run between myofilaments. Couplings are lacking. Ventricular fibres in T. marmorea show nexuses and desmosomes; in L. asellus only nexuses. The muscular ostia are tubular, and muscle fibres resemble those of the ventricle; nexuses are detected in T. marmorea and desmosomes in L. asellus. The only nervous elements observed are some nerve processes, structurally similar to those of other molluscs.
Similar content being viewed by others
References
Andrews EB (1976a) The fine structure of the heart of some prosobranch and pulmonate gastropodes in relation to filtration. J Moll Stud 42:199–216
Andrews EB (1976b) The ultrastructure of the heart and kidney of the pilid gastropod mollusc Marisa cornuarietis, with special reference to filtration throughout the Architaenioglossa. J Zool Res 179:85–106
Andrews EB, Little C (1971) Ultrafiltration in the Gastropod Heart. Nature London 234:411–412
Andrews EB, Little C (1972) Structure and function in the excretory systems of some terrestrial prosobranch snails (Cyclophoridae). J Zool Res 168:395–422
Baxter MI, Nisbet RH (1963) Features of the nervous system and heart of Archachatina revealed by the electron microscope and by electrophysiological recording. Proc Malac Soc London 35:167–177
Boer HH, Algera NH, Lommerse AW (1973) Ultrastructure of Possible Sites of Ultrafiltration in Some Gastropoda, with Particular Reference to The Auricle of the Freshwater Prosobranch Viviparus viviparus L. Z Zellforsch Mikrosk Anat 143:329–341
Bonga SEW, Boer HH (1969) Ultrastructure of the Reno-Pericardial System in the Pond Snail Lymnaea stagnalis (L). Z Zellforsch Mikrosk Anat 94:513–529
Erdélyi L, Halász N (1972) Electron-microscopical observations on the auricle of snail heart (Helix pomatia L.) with special regard to the structure of granulated cells. Acta Biol Szegel 18:253–267
Haller B (1882) Die Organisation der Chitonen der Adria. Arb Zool Inst Univ Wien 5:4
Hayes RL, Kelly RE (1969) Dense bodies of the Contractile System of Cardiac muscle in Venus mercenaria. J Morphol 127:151–162
Heyer CB, Kater SB, Karlsson UL (1973) Neuromuscular Systems in Molluscs. Am Zool 13:247–270
Humason GL (1967) In: Animal tissue techniques, 2nd ed. Freeman and Company, San Francisco, London
Irisawa H, Irisawa A, Shigeto N (1969) Effects of Na+ and Ca++ on the Spontaneous Excitation of the Bivalve Heart muscle. Comparative physiology of the heart, Current trends. Experientia Basel, Suppl 15:176–191
Irisawa H, Irisawa A, Shigeto N (1973) Physiological and morphological correlation of the functional syncytium in the bivalve myocardium. Comp Biochem Physiol 44A:207–219
Jensen H (1974) Ultrastructural Studies of the Hearts in Arenicola marina L. (Annelida: Polychaeta). Cell Tissue Res 156:127–144
Jensen H, Tjønneland A (1977) Ultrastructure of the Heart Muscle Cell of the Cuttlefish Rossia macrosoma (Delle Chiaje) (Mollusca: Cephalopoda). Cell Tissue Res 185:147–158
Karnovsky MJ (1965) A formaldehyde-glutaraldehyde fixative of high osmolarity for use in electron microscopy. J Cell Biol 27:137A
Kawaguti S (1963a) Electron Microscopy on the Heart Muscle of a Freshwater Bivalve, Unio doglasiae nipponensis. Biol J Okayama Univ 9:149–155
Kawaguti S (1963b) Electron Microscopy on the Heart Muscle of a Snail. Biol J Okayama Univ 9:140–148
Kawaguti S (1963c) Electron Microscopy on the Heart Muscle of the Cuttlefish. Biol J Okayama Univ 9:27–40
Kelly RE, Hayes RL (1969) The Ultrastructure of Smooth Cardiac Muscle in the Clam, Venus mercenaria. J Morphol 127:163–176
Myklebust R, Midttun B, Tjønneland A (1976) The Membrane Systems of the Cardiac Muscle Cell of Tmetonyx cicada O. Fabricius (Crustacea, Amphipoda). Cell Tissue Res 173:451–460
Nicaise G (1973) The Gliointerstitial System of Molluscs. Int Rev Cytol 34:251–332
Nicaise G, De Ceccatty MP, Baleydier CH (1968) Ultrastructure des connexions entre cellules nerveuses musculaires et glio-interstitielles chez Glossodoris. Z Zellforsch Mikrosk Anat 88:470–486
Nisbet RH, Plummer JM (1966) Further studies on the fine structure of the heart of Achatinidae. Proc Malac Soc London 37:199–208
Nisbet RH, Plummer JM (1968) The fine structure of cardiac and other molluscan muscle. Symp Zool Soc London 22:193–211
Nisbet RH, Plummer JM (1969) Functional Correlates of Fine Structure in the Heart of Achatinidae. Comparative physiology of the heart, Current trends. Experientia (Basel), Suppl 15:47–68
North RJ (1963) The Fine Structure of the Myofibres in the Heart of the Snail Helix aspersa. J Ultrastruct Res 8:206–218
Pelseneer P (1897) Sur la Morphologie des Branchies et des orifices renaux et genitaux des Chitons. Bull Scient Fr Belg V 31:23–30
Plate LH (1898) Die Anatomie und Phylogenie der Chitonen. Teil A. Zool Jahrb Suppl IV:1–243
Plate LH (1901) Die Anatomie und Phylogenie der Chitonen. Teil B and C. Zool Jahrb Suppl V:15–600
Plesch B (1977) An Ultrastructural Study of the Musculature of the Pond Snail Lymnaea stagnalis (L.). Cell Tissue Res 180:317–340
Prior DJ, Lipton BH (1977) An ultrastructural study of peripheral neurons and associated non-neural structures in the bivalve molluscs, Spisula solidissima. Tissue Cell 9:223–240
Reynolds ES (1963) The use of lead citrate at high pH as an electron-opaque stain in electron microscopy. J Cell Biol 17:208–212
Rutherford JG (1972) The Structure of the Ventricle of Elliptio complanatus, A Fresh-Water Lamellibranch. J Morphol 136:421–432
Schipp R, Schäfer A (1969) Vergleichende elektronenmikroskopische Untersuchungen an den zentralen Herzorganen von Cephalopoden (Sepia officinalis). Die Feinstruktur des Herzens. Z Zellforsch Mikrosk Anat 98:437–468
Seth ON, Kumar S, Rani S (1975) The neuroanatomy and histology of the heart of Chiton tuberculatus. Ind J Zool 3:12–16
Sommer JR, Steere RL, Johnson EA, Jewett PH (1972) Ultrastructure of Cardiac Muscle. A comparative review with emphasis on the musclefibres of the ventricles. In: South FE, Hannon JP, Willis JR, Pengelley ET, Alpert NR (eds) Hibernation and Hypothermia, Perspectives and Challenges Vol 1. Elsevier Publishing Company, Amsterdam-New York pp 291–355
Author information
Authors and Affiliations
Additional information
Supported by grants from the Norwegian Research Council for Science and Humanities
Rights and permissions
About this article
Cite this article
Økland, S. The heart Ultrastructure of lepidopleurus asellus (Spengler) and Tonicella marmorea (Fabricius) (Mollusca: Polyplacophora). Zoomorphology 96, 1–19 (1980). https://doi.org/10.1007/BF00310073
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00310073