title: Properties of an in vitro bioassay for hypertrehalosemic hormone of Blaberus discoidalis cockroaches.
abstract: The ability of the fat body to respond to the hypertrehalosemic action of corpora cardiaca-allata (CC + CA) extracts was measured in vitro with tissue from adult, male Blaberus discoidalis cockroaches. Only trehalose increased in the hemolymph when gland extracts were injected in vivo; likewise, only trehalose levels responded when fat bodies were exposed to gland extracts in vitro. Although fat bodies from 0-day-old animals gave the least response to gland extracts, all animals 5 or more days old showed elevated responses. A linear dose-response occurred between 0.02 and 0.08 CC + CA pair. Fat bodies did not show an in vitro, hypertrehalosemic response to insulin, glucagon, proctolin, dopamine, epinephrine, norepinephrine, serotonin, octopamine, or tyramine. A strong hypertrehalosemic response was found to both synthetic adipokinetic hormone and red-pigment concentrating hormone; however, reversed-phase, thin-layer chromatography of CC + CA extracts and adipokinetic hormone indicated that the hypertrehalosemic effect and the adipokinetic hormone were separate. This in vitro system comprises a relatively rapid, simple, and accurate bioassay for the hypertrehalosemic neurohormone of insects.
mesh_terms: D000273:Adipose Tissue / Q000187:drug effects*; D000818:Animals; D001681:Biological Assay; D003058:Cockroaches / Q000378:metabolism*; D004187:Disaccharides / Q000378:metabolism*; D005216:Fat Body / Q000187:drug effects* / Q000378:metabolism; D006458:Hemolymph / Q000032:analysis; D007301:Insect Hormones / Q000378:metabolism* / Q000494:pharmacology; D008297:Male; D014020:Tissue Extracts / Q000494:pharmacology; D014199:Trehalose / Q000378:metabolism*
chemical_list: D004187:Disaccharides; D007301:Insect Hormones; D014020:Tissue Extracts; D014199:Trehalose