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Membrane Potentials, Synaptic Responses, Neuronal Circuitry, Neuromodulation and Muscle Histology Using the Crayfish: Student Laboratory Exercises
16:16

Membrane Potentials, Synaptic Responses, Neuronal Circuitry, Neuromodulation and Muscle Histology Using the Crayfish: Student Laboratory Exercises

Published on: January 18, 2011

Multiple modulators act on the cardiac ganglion of the crab, Cancer borealis

Nelson D Cruz-Bermúdez1, Eve Marder

  • 1Volen Center for Complex Systems and Department of Biology, Brandeis University, MS-013, 415 South Street, Waltham, MA 02454, USA.

The Journal of Experimental Biology
|August 11, 2007
PubMed

Insights

Neuromodulators significantly impact neural circuits. In crabs, specific peptides like RPCH and CabTRP Ia excite the cardiac ganglion (CG), while AST-3 inhibits it, revealing complex CG modulation.

Area of Science:

  • Neuroscience
  • Marine Biology
  • Crustacean Physiology

Background:

  • Neural circuits' output is modulated by neuromodulators.
  • The crustacean cardiac ganglion (CG) controls heart contractions and is influenced by neurohormones.

Purpose of the Study:

  • To characterize the physiological actions of RPCH, CabTRP Ia, and AST-3 on the isolated CG of Cancer borealis.
  • To investigate the effects of other known peptides and small molecule transmitters on CG activity.

Main Methods:

  • Isolated cardiac ganglion (CG) preparation from the crab Cancer borealis.
  • Application of various peptides (RPCH, CabTRP Ia, AST-3, FLRFamides) and small molecules (dopamine, serotonin, proctolin, CCAP, GABA, cholinergic agonists).
  • Electrophysiological recording to monitor CG motor output and activity patterns.

Main Results:

  • RPCH and CabTRP Ia were found to excite the CG.
  • AST-3 strongly inhibited the CG's motor output.
  • Dopamine, serotonin, proctolin, CCAP, FLRFamides, and cholinergic agonists increased CG activity, while GABA inhibited it.

Conclusions:

  • The crustacean CG is multiply modulated by a diverse range of neurochemicals.
  • Multiple modulators likely play a crucial role in coordinating heart activity with physiological states and external stimuli.

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