IBBEA   24401
INSTITUTO DE BIODIVERSIDAD Y BIOLOGIA EXPERIMENTAL Y APLICADA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Some salt, not too much? how to solve this sensory complexity with the same gustatory receptors?
Autor/es:
PONTES G; BARROZO, RB; SFARA, V; CANO, A
Reunión:
Simposio; V Congreso ALAEQ; 2018
Resumen:
In all organisms, salts produce either appetitive oraversive responses depending on the concentration. While low-salt concentrationin food elicits positive responses to ingest, high-salt triggers aversion. B1?3ecause salts are essentialnutrients, their detection is crucial. Salts such as sodium chlorideparticipate in vital physiological functions maintaining the internalhomeostasis and neuronal transmission. Feeding on deficient or excessive saltsources could drive animals to physiological disorders. The taste sense helpsanimals to evaluate the quality of food, favoring the ingestion of nutrientsand avoiding the consumption of harmful or toxic compounds. Taste is then tunedto accept adequate concentrations of salts, according to each animal?snecessity. In this way, "tasteful" usually matches with "low"salt concentrations in food, and "distasteful" with "high"salt concentrations.Still the mechanisms involved in this dual behaviorhave just started to be uncovered in some organisms. In Rhodnius prolixus, using pharmacological, electrophysiological andbehavioral assays, we demonstrated that upon high-salt detection in food anitric oxide (NO) dependent cascade is activated. This activation involves asoluble guanylate cyclase (sGC) and the production of cyclic guanosinemonophosphate (cGMP). Thus, appetitive responses to low-salt diets turn toaversion whenever this cascade is activated. Conversely, insects feed overaversive high-salt solutions when it is blocked by reducing NO levels or byaffecting the sGC activity. The activation of NO/sGC/cGMP cascade commands theavoidance feeding behavior in R.prolixus. Thus, we propose that the dual behavior to salts is just theresult of the activation or not of a NO/sGC/cGMP cascade. Investigations inother insect species should examine the possibility that high-salt aversion ismediated by NO/sSG/cGMP signaling.