Bitter taste perception in the blood-sucking insect Rhodnius prolixus

ISABEL ORTEGA; GINA B. PONTES; ROMINA BARROZO

Congreso; II ALAEQ; 2012

The taste sense plays a crucial role in animals? life informing them about the nutritional quality of a food source. Moreover it provides a means of discrimination between nutrient-rich substrates, from harmful, mostly bitter-tasting. Rhodnius prolixus is a hematophagous insect that feeds on blood from small vessels of vertebrate hosts. Once insects pierced the host skin, they move their mouthparts until a venule or an arteriole is reached. Insects pump a small quantity of blood initiating the sampling phase of food. During this period, the taste sense might become crucial in terms of the assessment of food quality. Our goal in this work was to determine whether the bitter taste is perceived by bugs (beyond the well-known phagostimulant ATP).The feeding response of bugs was analyzed by measuring the weight gain of insects to different test diets in an artificial feeder set-up during 10 min. Our results show that R. prolixus can perceive different bitter taste sense in dose-dependent manner, although this was only evident in the presence of ATP. Notably, bitter compounds have an inhibitory effect on the feeding behavior of bugs. The importance the taste sense plays in the feeding behavior, for vectors of Chagas disease in Latin America, begins to be understood.