STUDIES ON THE INFLUENCE OF SYNTHETIC ADIPOKINETIC HORMONE AND SOME ANALOGS ON CYCLIC-AMP LEVELS IN DIFFERENT ARTHROPOD SYSTEMS

Injection of synthetic adipokinetic hormone (AKH) into adult Locusta migratoria resulted in an increase of cyclic AMP level in the fat body. No differences in response between male or female insects could be observed. the accumulation of cyclc AMP was time dependent with a maximum effect 6 min after injection. The effect was dose dependent; approximately 2 pmol of synthetic AKH were needed to produce a singificant elevation of cyclic AMP. Studies with AKH analogs revealed that only peptides with a minimum of the first eight amino acids were able to elevate the cyclic AMP level. No analog, however, was as active as the true hormone. Although synthetic AKH did elevate the glucose concentration in the hemolymph as well as the cyclic AMP content of the claw muscle of the fiddler crab, this response was always less by comparison with purified hyperglycemic hormone of Cancer magister. © 1979.