Primitive nervous systems: electrical activity in the nerve cords of the parasitic flatworm, Gyrocotyle fimbriata.

@article{Keenan1984PrimitiveNS,
  title={Primitive nervous systems: electrical activity in the nerve cords of the parasitic flatworm, Gyrocotyle fimbriata.},
  author={Larry Keenan and Harold Koopowitz and Michael H. Solon},
  journal={The Journal of parasitology},
  year={1984},
  volume={70 1},
  pages={
          131-8
        }
}
A large compound potential (LCP) could be evoked in the longitudinal nerve cords of Gyrocotyle fimbriata. This potential was graded and showed decremental conduction. Decrement was more pronounced in the posterior direction and was exponential with distance, dropping to 50% of its initial value in less than 5 mm. Conduction velocities in the anterior to posterior direction were greater than the reverse direction (means = 37.3 cm sec-1 vs. means = 30.3 cm sec-1). Single suprathreshold stimuli… 
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References

SHOWING 1-10 OF 16 REFERENCES
ORGANIZATION OF PRIMITIVE NERVOUS SYSTEMS. NEUROMUSCULAR PHYSIOLOGY OF GYROCOTYLE URNA, A PARASITIC FLATWORM
TLDR
The nervous system consists of two longitudinal nerve cords with commissures at each end, and the anterior acetabular commissure is used to synchronize the spontaneous activity of the two sides.
Conduction Along the Ventral Nerve Cord of a Hemichordate Worm
TLDR
Compound and all-or-none pulses have been recorded from the ventral nerve cord of a hemichordate worm, suggesting that four conduction pathways may be present in the cord.
Electrical Activity in the Radial Nerve Cord And Ampullae of Sea Urchins
TLDR
Evidence of a feedback from damaged tube feet to the cord, suppressing ampulla response to cord stimulation, was found and two components of the potential can be identified and have different thresholds to stimulation, conduction velocities and amplitudes.
The electrical activity of the radial nerve in Diadema antillarum Philippi and certain other echinoids.
TLDR
The response of Diadema has a double peak which is shown to represent responses of nerves differing in excitability and conduction velocity, which is related to inhibition of spine movements excited photically.
Electrophysiology and luminescence of an ophiuroid radial nerve.
  • P. Brehm
  • Biology
    The Journal of experimental biology
  • 1977
TLDR
The coexistence of both neurones and luminescent cells within the RNC, the similar morphology of the two, and the similar ionic dependency of luminescence propagation and recorded electrical activity suggests that luminecent cells may be modified neurones.
Physiology and in situ identification of putative aminergic neurotransmitters in the nervous system of Gyrocotyle fimbriata, a parasitic flatworm.
TLDR
The experiments indicate that the fluorescing substance in the neurones is not a known catecholamine and could be an amino acid, and this activity can be blocked by application of APB, an aminergic blocking agent.
The gross anatomy and histology of the nervous system of the metacestode of Hymenolepis microstoma.
TLDR
The central nervous system of the metacestode of Hymenolepis microstoma consists of three levels of ganglia, and the ganglia and large commissures consist of a rind of nerve cell bodies surrounding a compact core of neuropile.
Tryptaminergic and dopaminergic responses of Schistosoma mansoni.
TLDR
Pharmacological evidence is reported indicating that 5-hydroxytryptamine is an excitatory neurotransmitter in Schistosoma manasoni, and male worms from single-sex infections differed in their lengthening response from males paired with females.
The effect of lysergic acid diethylamide, 5-hydroxytryptamine, and related compounds on the liver fluke, Fasciola hepatica.
  • T. Mansour
  • Biology, Chemistry
    British journal of pharmacology and chemotherapy
  • 1957
TLDR
Evidence which suggests the presence of tryptamine receptors in the trematode is discussed, and other analogues such as yohimbine, harmine, and dopamine depressed rhythmical movement and antagonized the stimulant action of 5-hydroxytryptamine and lysergic acid diethylamide.
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