IBBEA   24401
INSTITUTO DE BIODIVERSIDAD Y BIOLOGIA EXPERIMENTAL Y APLICADA
Unidad Ejecutora - UE
artículos
Título:
Kissing bugs can generalize and discriminate between different bitter compounds
Autor/es:
MASAGUE, S; PONTES, G; BARROZO, RB; ASPARCH, Y; MINOLI, S
Revista:
JOURNAL OF PHYSIOLOGY (PARIS)
Editorial:
ELSEVIER SCI LTD
Referencias:
Lugar: Amsterdam; Año: 2016 vol. 110 p. 99 - 106
ISSN:
0928-4257
Resumen:
Animalsmake use of contact chemoreception structures to examine the quality of potentialfood sources. During this evaluation they can detect nutritious compounds thatpromote feeding and recognize toxins that trigger evasive behaviors. Althoughanimals can easily distinguish between stimuli of different gustatory qualities(bitter, salty, sweet, etc.), their ability to discriminate between compoundsof the same quality may be limited. Numerous plants produce alkaloids,compounds that elicit aversive behaviors in phytophagous insects and almostuniformly evoke a bitter taste for man. In hematophagous insects, however, theeffect of feeding deterrent molecules has been barely studied. Recent studies showedthat feeding in Rhodnius prolixus canbe negatively modulated by the presence of alkaloids such as quinine (QUI) and caffeine(CAF), compounds that elicit similar aversive responses. Here, we applied associativeand non-associative learning paradigms to examine under two behavioral contextsthe ability of R. prolixus to distinguish,discriminate and/or generalize between these two bitter compounds, QUI and CAF.Ourresults show that bugs innately repelled by bitter compounds can change their behaviorfrom avoidance to indifference or even to preference according to their previousexperiences. After an aversive operant conditioning with QUI or CAF, R. prolixus modified its behavior in a directbut also in a cross-compound manner, suggesting the occurrence of a generalizationprocess between these two alkaloids. Conversely, after a long pre-exposure to eachalkaloid, bugs decreased their avoidance to the compound used duringpre-exposure but still expressed an avoidance of the novel compound, provingthat QUI and CAF are detected separately. Our results suggest that R. prolixus is able to discriminate betweenQUI and CAF, although after an associative conditioning they express a symmetricalcross-generalization. This kind of studies adds insight into the gustatorysense of a blood-sucking model but also into the learning abilities of hematophagousinsects.