Abstract
The parasitoid wasp Ampulex compressa injects venom into the brain of the American cockroach, targeting the central complex, a sensory-motor region. The venom induces grooming, followed by long-lasting hypokinesia. While grooming is attributed to dopamine in the venom, the mechanisms underlying hypokinesia remain unclear. Given the role of dopamine in modulating arousal and locomotion in insects, and our finding of long-term impairment in venom-induced grooming behavior, we hypothesized that the mechanisms behind long-term grooming impairments may provide insight into the mechanisms driving hypokinesia. We analyzed the recovery profile of venom-induced grooming in stung cockroaches and investigated dopamine receptor involvement through D1-like receptor agonist injections into the central complex. Our results reveal a deficient grooming response to a second sting 1 month after the first, and that this change is not caused by a lasting impairment of D1 receptor signaling but rather a complex interaction between venom components and the recovered brain.