Abstract

1. With a view to clarifying the role of oxygen in the olfactory reception of insects, the intact antenna of the male American cockroach (Periplaneta americana) was studied under normal conditions and during reversible anoxia, external or tracheal, using an electroantennogram (EAG) elicited by a sex pheromone stimulation. As a first step, the anatomical and electrical characteristics of the antenna were investigated. 2. Based on the microanatomical study, a cockroach antenna was characterized by structural parameters reflecting the haemolymph and gas exchange in the antenna. Valves in the wall of a haemolymphatic vessel were discovered. 3. The resting DC background voltage (DCBV) and the EAG were continuously recorded and proved to be more strongly affected by tracheal anoxia than by anoxia from the outside. 4. A minimal electrical model of the antenna based on the Thurm-Kaissling-De Kramer equivalent circuit of a sensillum was shown to be valid to explain the origin of the DCBV and EAG as well as their changes after oxygen cutoff and resumption. 5. Two formal opposing processes, excitation and desensitization, probably related to the receptor mechanisms, have been used to interpret the kinetics of the EAG and the effect of anoxia on EAG parameters. The desensitization is thought to be more sensitive to oxygen lack than the excitation.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.