Physiological role of individual neuropeptides in Triatomines in the search of targets for new insecticides.

NATALIA, CAPRIOTTI; JUAN P, IANOWSKY; NICHOLS, RUTHAND; SHEILA, ONS

Cafayate, Salta

Conferencia; Invertebrate Neuropeptide Conference; 2017

International Neuropeptide Society

Given that haematophagous insects ingest large quantities of blood in a single meal, theyshould undergo a rapid post-prandial diuresis in order to maintain the homeostasis. Theactivation of diuresis is possible because of the excretory activity of the Malpighian tubules,facilitated by the increase on frequency of the contractions and the peristaltic waves in theanterior midgut. Both, diuretic and antidiuretic processes are regulated by neuropeptides. Hence,the design of molecules capable of interfering with the neuroendocrine system disturbing normalphysiology has been proposed as a novel route of the obtaining of new insecticides to manageharmful insects. We evaluated the activity of the neuropeptides CCH-amide and sNPF in the diuresis andthe myotropic activity of Rhodnius prolixus byRNAi mediated gene silencing coupled to in vivoassays. Furthermore, we performed in vitro assays to measure the effects of these twoneuropeptides in the secretion rate by Malpighian tubules and in the contraction rate of aorta andanterior midgut. The results suggest a myoregulatory activity for RhoprsNPF and a role of RhoprCCH-amide in the regulation of diuresis. This represents the first report exploring the physiologicalrole of these two neuropeptides in kissing bugs, in the context of the scientific effort to identifysuitable targets for new insecticides.