Nitric oxide modulates de ingestión of ATP in Rhodnius prolixus

R. BARROZO, V. SFARA, G. PONTES AND G. MOUGABURE CUETO

Huerta Grande Cordoba

Congreso; II Latin American Association of Chemical Ecology; 2012

Animals in the presence of a food source can test its quality by means of taste, and this allows them to make the final decision of feeding on that source or searching for another one. Nitric oxide (NO) is a neuromodulator which participates in a great number of physiological and biochemical processes in almost all living organisms. In insects, NO modifies sensory inputs and behavioural responses associated to chemical stimuli, both olfactory and gustatory [1]. In this work we studied the role of NO in the recognition and acceptance of a food source by the bug Rhodnius prolixus. A solution of 10-3 M of ATP was offered as a food source. Insects were previously fed for 1 minute on solutions of the NO donor S-nitroso-acetylcysteine (SNAC) of different concentrations. Pre-treated insects were then allowed to feed on the solution of ATP for 5 minutes. Ingestion was determined by weighing insects before and after feeding on ATP. Insects with different starvation periods were used (15-20 days and 30-45 days). We observed a dose-dependent decrease in the ingestion of ATP in insects starved for 15-20 days. The ingestion of ATP was almost suppressed in insects pre-treated with the highest dose of SNAC tested (200 mM). However, insects starved for 30-45 days and pre-treated with this same concentration of SNAC did not show any decrease in the ingestion of ATP. A role of NO in the evaluation of the quality of a food source in R. prolixus is suggested. Moreover, this effect varies depending on insect´s motivation for feeding given by its starvation period.