Peptidergic innervation of the crop and the effects of an ingested nonpeptidal agonist on longevity in female Musca domestica (Diptera: Muscidae).

Dromyosuppressin (DMS) immunoreactive neurons were discovered running along the crop duct and on the surface of the crop in the house fly, Musca domestica L. DMS is a myoinhibitory neuropeptide that has been shown to inhibit crop contractions, in vitro, in the blow fly, Phormia regina (Meigen), and in Drosophila melanogaster Meigen. Various concentrations of benzethonium chloride (Bztc), an agonist of DMS with shown inhibitory effects on blow fly crop contractions, were fed to adult female M. domestica. Flies exhibited a dose-dependent mortality; avoidance and subsequent dehydration are probably the cause of the low survivorship at higher Bztc concentrations.