Effects of horsefly (Tabanidae) salivary gland extracts on isolated perfused rat heart.
The speed with which horseflies (Diptera: Tabanidae) obtain a bloodmeal suggests they have potent vasodilators. We used isolated perfused rat heart to examine the vasoactivity of salivary gland extracts (SGEs) of three horsefly species, Hybomitra bimaculata Macquart, Tabanus bromius Linnaeus and Tabanus glaucopis Meigen. Administration of horsefly SGEs to the heart produced biphasic coronary responses: a decrease and subsequent increase in coronary flow (CF), characterized by initial vasoconstriction followed by prolonged vasodilation of coronary vessels. However, although SGEs of H. bimaculata induced a significant decrease in left ventricular pressure (LVP), the effect on changes in CF was not significant except at the highest dose tested. The ability to reduce LVP without significantly lowering CF, or affecting heart rate and rhythm, represents a unique set of properties that have considerable therapeutic potential if they can be reproduced by a single molecule.
Rajská
P
P
Institute of Zoology, Slovak Academy of Sciences, Bratislava, Slovakia.
Knezl
V
V
Kazimírová
M
M
Takác
P
P
Roller
L
L
Vidlicka
L
L
Ciampor
F
F
Labuda
M
M
Weston-Davies
W
W
Nuttall
P A
PA
D000818:Animals; D003326:Coronary Circulation; D003331:Coronary Vessels / Q000187:drug effects; D004175:Diptera / Q000737:chemistry* / Q000145:classification / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D005247:Feeding Behavior / Q000502:physiology; D006339:Heart Rate / Q000187:drug effects; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012469:Salivary Glands / Q000737:chemistry*; D013045:Species Specificity; D014020:Tissue Extracts / Q000494:pharmacology*; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents / Q000494:pharmacology*; D017725:Ventricular Pressure / Q000187:drug effects
D014020:Tissue Extracts; D014665:Vasodilator Agents