Neuropeptide Mimetics: The Physiological Effects of Kinin and CAPA Analogs in Rhodnius prolixus

Neuropeptide Mimetics: The Physiological Effects of Kinin and CAPA Analogs in Rhodnius prolixus

In the Chagas disease vector Rhodnius prolixus, the kinin and CAPA neuropeptides modulate a host of feeding and diuresis-related behaviours that are implicated in disease transmission. CAPA and kinin neuropeptide analogs have been developed to elicit potent changes in physiology, to be later incorporated in novel pest-control strategies. Here, the effects of kinin and CAPA analogs were investigated on feeding and diuresis-related tissues, with the kinin and CAPA analogs inducing physiological changes in vivo and in vitro. Within the hindgut, novel intracellular interactions were uncovered between RhoprCAPA, Rhopr-kinin, and serotonin [5- hydroxytryptamine (5-HT)]. Following identification and sequencing of the Rhopr-kinin receptor, the receptor transcript was observed throughout the gut, with RNA interference (RNAi)-mediated knockdown of the receptor causing reductions in hindgut contractions and increasing the size of blood meal consumed. Overall, these findings highlight the role of kinin and CAPA within R. prolixus, and the promise of their neuropeptide analogs to be used as lead compounds in pest- control strategies.