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Updated: Aug 30, 2026

Studying the Activity of Neuropeptides and Other Regulators of the Excretory System in the Adult Mosquito
Published on: August 24, 2021
Vasodilatory activity in horsefly and deerfly salivary glands
P Rajská1, O Pechánová, P Takác
1Institute of Zoology, Slovak Academy of Sciences, Bratislava, Slovakia.
Abstract:
Salivary gland extract (SGE) of four horsefly species (Hybomitra bimaculata Macquart, Hybomitra ciureai Séguy, Tabanus bromius L., Tabanus glaucopis Meigen) and one deerfly species (Chrysops relictus Meigen) (Diptera: Tabanidae) were shown to contain vasodilatory activity. Aliquots equivalent to 1, 5 and 10 pairs of salivary glands (SG) relaxed rat femoral artery (with intact endothelium) pre-constricted with phenylephrine. Vasodilatory activity was dose-dependent. SGE of one horsefly species (Haematopota pluvialis L.) did not induce relaxation. The kinetics of vasodilation induced by SGE of four horsefly species differed from the deerfly. These results indicate that tabanid species may produce more than one type of vasodilator to aid blood feeding.
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