Advertisement

Journal of comparative physiology

, Volume 142, Issue 2, pp 189–198 | Cite as

The responses of the antennular muscles of the brachyuranScylla serrata (Forskål) (Portunoidea, Brachyura) to repetitive activation of specific motoneurons

  • P. J. Snow
Article

Summary

  1. 1.

    The electrical and mechanical responses in all the antennular muscles of the medial and distal segments of the antennule ofScylla serrata, in response to repetitive stimulation of all the antennular motoneurons at 10, 20, 50 and sometimes 100 Hz, are described.

     
  2. 2.

    In muscle group 30 both M30V and M30D contract and relax relatively slowly. The EJPs of motoneurons to this muscle group always show some facilitation. Tension production always occurs smoothly and is accompanied by a plateau of depolarisation in the muscle fibres.

     
  3. 3.

    In muscle group 31 both M31Sv and M31Sm contract and relax slowly whereas M31F contracts and relaxes rapidly. Motoneuron A31S1 gives rise to facilitatory EJPs in both ‘slow’ muscles whereas the large EJPs of A31S2 do not show facilitation. Motoneuron A31F gives rise to large, facilitatory EJPs in M31F whereas motoneuron A31–32F gives rise to very large EJPs in M31F which show some antifacilitation even at 20 Hz.

     
  4. 4.

    In muscle group 32, M32F contracts and relaxes very rapidly whereas M32S contracts and relaxes slowly. Even at 50 Hz the EJPs of motoneurons A32F and A31–32F do not show any facilitation or antifacilitation. The EJPs of motoneuron A32S1 are relatively large and do not show any facilitation. Each of these EJPs elicits a small, slow contraction in M32S and summation of these results in the production of a plateau of tension even at 10 and 20 Hz. The EJPs of motoneuron A32S2 facilitate only slighly and evidence suggests that the plateau of tension produced arises, in part at least, from the summation of small slow contractions produced by each EJP.

     
  5. 5.

    Motoneuron A32F-S gives rise to facilitating EJPs in M32F but non-facilitating EJPs in M32S. Paradoxically this motoneuron does not produce any tension in M32S but at 100 Hz does produce large, possibly electrogenic, responses in M32F which are accompanied by twitch contractions.

     
  6. 6.

    The behavioural role of particular antennular motoneurons is discussed and compared with previously published data on the hermit crab antennule.

     

Keywords

Muscle Fibre Mechanical Response Muscle Group Distal Segment Hermit Crab 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Abbreviations

E.J.P.

excitatory junction potential

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Atwood HL (1973) An attempt to account for the diversity of crustacean muscles. Am Zool 13:235–378Google Scholar
  2. Atwood HL, Hoyle G (1965) A further study of the paradox phenomenon of crustacean muscle. J Physiol 181:225–234Google Scholar
  3. Atwood HL, Hoyle G, Smyth T (1965) Electrical and mechanical responses of single innervated crab-muscle fibres. J Physiol 180:449–482Google Scholar
  4. Frank E (1973) Matching of facilitation at the neuromuscular junction of the lobster: A possible case for influence of muscle on nerve. J Physiol 233:635–658Google Scholar
  5. Hoyle G, Wiersma CAG (1958) Coupling of membrane potential to contraction in crustacean muscles. J Physiol 143:441–453Google Scholar
  6. Maynard DM, Dingle H (1963) An effect of eyestalk ablation on antennular function in the spiny lobster,Panulirus argus. Z Vergl Physiol 46:515–540Google Scholar
  7. Reuben JP, Brandt PW, Garcia H, Grundfest H (1967) Excitation-contraction coupling in crayfish. Am Zool 7:623–646Google Scholar
  8. Schmitt BC, Ache BW (1979) Olfaction: Responses of a decapod crustacean are enhanced by flicking. Science 205:204–206Google Scholar
  9. Snow PJ (1973a) The antennular activities of the hermit crab,Pagurus alaskensis (Benedict). J Exp Biol 58:745–765Google Scholar
  10. Snow PJ (1973b) The motor innervation and musculature of the hermit crab,Pagurus alaskensis (Benedict). J Exp Biol 58:767–784Google Scholar
  11. Snow PJ (1975) Patterns of activity in the antennular motoneurons of the hermit crab,Pagurus alaskensis (Benedict). J Exp Biol 63:1–15Google Scholar
  12. Snow PJ (1980) The motor innervation and the musculature of the antennule of the Australian mud crab,Scylla serrata (Forskal) (Portunoidea, Brachyura). Proc R Soc Lond [Biol] 207:219–237Google Scholar
  13. Wiersma CAG, Harreveld A van (1938) The influence of the frequency of stimulation on the slow and the fast contraction in crustacean muscle. Physiol Zool 11:75–81Google Scholar
  14. Wiersma CAG, Ripley SH (1952) Innervation patterns of crustacean limbs. Physiol Comp Eocol 2:391–405Google Scholar

Copyright information

© Springer-Verlag 1981

Authors and Affiliations

  • P. J. Snow
    • 1
  1. 1.Department of Neurobiology, Research School of Biological SciencesAustralian National UniversityCanberra CityAustralia

Personalised recommendations