6,486 Studies Reviewed. 85.2% of Original Studies Found Biological Effects. The Evidence is Clear.
Shield Your Body
Brain & Nervous SystemPart of the Glaser Archive

THE EFFECT OF ELECTRICAL STIMULATION ON THE LEVELS OF FREE AMINO ACIDS AND RELATED COMPOUNDS IN THE SNAIL BRAIN

Bioeffects Seen

N. N. OSBORNE, B. POWELL, G. A. COTTRELL · 1971

Share:

A 1971 study found that electrical stimulation of snail nerve trunks lowered levels of several amino acids in the snail brain, with the greatest reduction, 16%, for tryptophan.

Plain English Summary

Summary written for general audiences

This 1971 study examined how electrical stimulation affected amino acid levels in the snail brain. Researchers stimulated selected nerve trunks of Helix pomatia snails with square wave pulses (15 V, 10 msec, 3 per second) for 1 hour and then analyzed the circumoesophageal ganglia. Tyrosine, tryptophan, ornithine, lysine and several other amino acids decreased, while 5-hydroxyindole increased by about 24%.

Why This Matters

This research from 1971 used the snail brain to ask how electrical stimulation changes the levels of free amino acids in nervous tissue. The authors note that some of these amino acids may be important in the transmission of information across certain synaptic junctions, and that the roles of these substances in neurons are far from completely understood. Stimulation was applied to selected nerve trunks with square wave pulses, not radiofrequency fields.

Stimulation decreased tyrosine, tryptophan, ornithine, lysine, phenylalanine, leucine, isoleucine, proline, valine, glycine, asparagine and serine, with the greatest reduction, 16%, for tryptophan. 5-hydroxyindole increased by about 24%, and alanine and an unknown substance also increased. The authors suggest the decreases may reflect changes in protein synthesis and transport, or the metabolism of neurotransmitters such as dopamine, noradrenaline and serotonin.

Figures from the Original Paper

Diagrams extracted from the original research document.

diagramPage 2 - AI-described figure: Fig. 1: Autoradiograms showing substances in a control brain extract and a stimulated brain extract after reaction with [14C]dansyl-chloride, demonstrating the effect of stimulation on substance distribution.
p. 2 of the original PDF
diagramPage 3 - Fig. 2: Autoradiograms and corresponding map of [14C]dansyl-compounds in (A) control brain extract and (B) stimulated brain extract chromatographed in 3 different solvent systems.
p. 3 of the original PDF

Exposure Information

Specific exposure levels were not quantified in this study. Duration: 1 hour

Study Details

To study the effects of electrical stimulation on the levels of free amino acids and related compounds in the snail brain

Specimens of Helix pomatia were obtained from L. Haig and Co. Ltd., Newdigate, Surrey. The snails we...

In the stimulated brain there was a decrease in concentrations of tyrosine, tryptophan, ornithine, l...

Electrical stimulation causes changes in amino acid levels in the snail brain. The decrease in several amino acids may reflect changes in protein synthesis and transport, or the metabolism of neurotransmitters such as dopamine, noradrenaline and serotonin. The increase in 5-hydroxyindole may reflect increased release of serotonin at serotonergic synapses. The increase in alanine and unknown substance (spot 15) requires further investigation to identify their chemical nature.

Cite This Study
N. N. OSBORNE, B. POWELL, G. A. COTTRELL (1971). THE EFFECT OF ELECTRICAL STIMULATION ON THE LEVELS OF FREE AMINO ACIDS AND RELATED COMPOUNDS IN THE SNAIL BRAIN.
Show BibTeX
@article{the_effect_of_electrical_stimulation_on_the_levels_of_free_amino_acids_and_relat_g3763,
  author = {N. N. OSBORNE and B. POWELL and G. A. COTTRELL},
  title = {THE EFFECT OF ELECTRICAL STIMULATION ON THE LEVELS OF FREE AMINO ACIDS AND RELATED COMPOUNDS IN THE SNAIL BRAIN},
  year = {1971},
  
  
}
No DOI on file for this study.

Quick Questions About This Study

The authors note that some free amino acids in nervous tissue may be important in energy transfer and protein synthesis, and also in the transmission of information across certain synaptic junctions. They studied the effects of electrical stimulation on amino acid levels in the circumoesophageal ganglia (the brain) of the snail Helix pomatia as one approach to learning more about the roles of these substances.
Stimulation decreased tyrosine, tryptophan, ornithine, lysine, phenylalanine, leucine, isoleucine, proline, valine, glycine, asparagine and serine. The greatest reduction was 16% for tryptophan, while 5-hydroxyindole increased by about 24%, and alanine and an unknown substance also increased.
Stimulation of the nerve trunks decreased the levels of several amino acids, and 5-hydroxyindole increased by about 24%. Levels of taurine, methionine, GABA, glutamine, threonine, arginine, ε-lysine, α-amino-histidine, cystine and aspartic acid were not influenced by stimulation.
Electrical stimulation here means square wave pulses, 15 V in amplitude and 10 msec in duration, applied at 3 per second to selected nerve trunks of Helix pomatia snails. Preparations were stimulated for 1 hour and then immediately dissected for amino acid analysis.
The authors suggest the decreases in several amino acids may reflect changes in protein synthesis and transport, or the metabolism of neurotransmitters such as dopamine, noradrenaline and serotonin. They suggest the increase in 5-hydroxyindole may reflect increased release of serotonin at serotonergic synapses.