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Repellency, toxicity, and physiological actions of low molecular weight basic amines in mosquitoes
Liu Yang1,2, Fabien Demares1,3, Edmund J Norris4
1Emerging Pathogens Institute, Entomology and Nematology Department, University of Florida, Gainesville, FL, USA.
Pest Management Science
|July 12, 2024
Summary
Basic amines like triethylamine (TEA) repel mosquitoes and cause paralysis by blocking nerve signals, particularly potassium (K+) channels. This study reveals their neurophysiological effects and insecticidal mechanisms.
Area of Science:
- Neuroscience
- Toxicology
- Entomology
Background:
- Investigated behavioral responses and toxicity of 1-methylpiperazine, 1-methylpyrrolidine, and triethylamine (TEA).
- Explored compounds previously suggested to cause anosmia in mosquitoes.
Purpose of the Study:
- Determine the neurophysiological mechanisms of basic amine toxicity in insects.
- Clarify the role of potassium channels in basic amine action.
- Assess behavioral and electrophysiological responses to basic amines.
Main Methods:
- Observed behavioral responses (repellency, paralysis) in Aedes aegypti mosquitoes.
- Conducted electrophysiological experiments on Drosophila melanogaster larval CNS and cockroach mechanoreceptors.
- Performed patch-clamp studies on voltage-gated potassium channels.
- Recorded electroantennogram (EAG) signals from mosquito antennae.
Main Results:
- Basic amines caused repellency, flightlessness, knockdown, and paralysis in mosquitoes, dose-dependently.
- Demonstrated K+ channel blockage in insect CNS and peripheral neurons.
- Observed neuronal hyperexcitation in a Shaker Kv1 mutant, confirming K+ channel involvement.
- Detected strong EAG signals on mosquito antennae, but not linked to anosmia.
Conclusions:
- Neurophysiological effects of basic amines align with K+ channel blockage.
- Low-dose effects include repellency and bradykinesia (slowness of movement).
- Findings offer insights into the biological activity and insecticidal mechanisms of basic amines.
Keywords:
1‐methylpiperazine1‐methylpyrrolidineAedes aegyptiDrosophila melanogasterPeriplaneta americanacentral nervous systemelectroantennogrampotassium channeltriethylamineMore Related Videos
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