Triethylamine as a potential anesthetic agent for the study of mosquito heart physiology

Triethylamine, purchased under the trade name Fly-Nap, is widely used to anesthetize the fruit fly, Drosophila melanogaster.  In mosquitoes, however, triethylamine has largely been used in studies where the application of high concentrations of this chemical leads to insect death.  The purpose of this study was to determine whether low-level exposure to triethylamine effectively anesthetizes mosquitoes, and to determine whether such anesthesia interferes with normal circulatory functions.  To test this, Anopheles gambiae mosquitoes were exposed to various doses of triethylamine and (1) their cardiac physiology was optically recorded, and (2) their survival was monitored.  Analysis of the data revealed that while high-level exposure to triethylamine significantly decreases heart contraction rates and mosquito survival, low-level exposures anesthetize mosquitoes for several hours, do not affect heart physiology, and do not reduce mosquito survival.  These data suggest that brief exposure to triethylamine is suitable for mosquito anesthesia and may be ideal for experiments were mosquitoes must be restrained for prolonged periods of time.