Triggering the proboscis extension reflex (PER) in Rhodnius prolixus
Raquel A Ferreira1, Marcelo G Lorenzo1, Claudio R Lazzari2
1Instituto René Rachou/FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil.
Journal of Insect Physiology
|May 3, 2021
Summary
Kissing bugs, Rhodnius prolixus, accurately estimate distances to warm targets using thermal cues and free walking. Mechanical stimuli also influence their bite initiation, revealing a novel sensory integration for host-seeking behavior.
Area of Science:
- * Entomology
- * Sensory Biology
- * Vector Biology
Background:
- * Blood-sucking insects like Rhodnius prolixus use host body heat for short-range orientation.
- * Understanding how these vectors assess thermal cues is crucial for controlling disease transmission.
Purpose of the Study:
- * To investigate how Rhodnius prolixus estimates distance to a thermal source.
- * To determine the role of thermal and mechanical cues in triggering the Proboscis Extension Reflex (PER).
Main Methods:
- * Blindfolded Rhodnius prolixus nymphs were exposed to thermal sources (35°C or 40°C) under open- and closed-loop conditions.
- * The Proboscis Extension Reflex (PER) was observed in relation to distance and temperature.
- * Mechanical stimuli were integrated with thermal cues to assess their combined effect.
Main Results:
- * Nymphs accurately estimated distance to thermal sources using only thermal information.
- * PER was most frequent at 5 mm from the thermal source, independent of temperature.
- * Free walking was necessary for precise distance estimation.
- * Mechanical stimuli were found to influence PER triggering, indicating mechanoreception's role in bite elicitation.
Conclusions:
- * Rhodnius prolixus utilizes thermal cues and locomotion for accurate thermal source distance assessment.
- * This study provides the first evidence of mechanoreception influencing bite elicitation in blood-sucking insects.
- * Findings offer new insights into sensory integration models for host-seeking behavior in disease vectors.
