Nitric oxide modulates the ingestion of ATP in Rhodnius prolixus.

5. BARROZO RB, SFARA V, PONTES G, MOUGABURE CUETO G.

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 orsearching for another one. Nitric oxide (NO) is a neuromodulator whichparticipates in a great number of physiological and biochemical processes inalmost all living organisms. In insects, NO modifies sensory inputs andbehavioural responses associated to chemical stimuli, both olfactory andgustatory [1]. In this work we studied the role of NO in the recognition andacceptance of a food source by the bug Rhodnius prolixus. A solution of 10-3 M ofATP was offered as a food source. Insects were previously fed for 1 minute onsolutions of the NO donor S-nitroso-acetylcysteine (SNAC) of differentconcentrations. Pre-treated insects were then allowed to feed on the solution ofATP for 5 minutes. Ingestion was determined by weighing insects before andafter feeding on ATP. Insects with different starvation periods were used (15-20days and 30-45 days). We observed a dose-dependent decrease in the ingestionof ATP in insects starved for 15-20 days. The ingestion of ATP was almostsuppressed in insects pre-treated with the highest dose of SNAC tested (200mM). However, insects starved for 30-45 days and pre-treated with this sameconcentration of SNAC did not show any decrease in the ingestion of ATP. A roleof 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 byits starvation period.