The influence of neuropeptides on Malpighian tubule writhing and its significance for excretion.
Diuretic peptides (locustakinin and Locusta-DH) increase the spontaneous contractile activity of visceral muscle fibers associated with Malpighian tubules from the migratory locust (Locusta migratoria) at concentrations that increase urine production. Muscle activity is shown to assist the flow of material in the tubule lumen, but is not essential for diuresis. Tubule writhing also serves to reduce unstirred layers (USLs) at the basolateral surface of the epithelium and thereby facilitates the excretion of solutes entering the lumen by passive diffusion.
Coast
G M
GM
Department of Biology, Birkbeck College, London, UK. g.coast@biol.bbk.ac.uk
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002121:Calcium Channel Blockers / Q000494:pharmacology; D004231:Diuresis / Q000187:drug effects; D004232:Diuretics / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005260:Female; D006110:Grasshoppers / Q000502:physiology*; D066298:In Vitro Techniques; D019476:Insect Proteins / Q000494:pharmacology; D007444:Inulin; D008317:Malpighian Tubules / Q000502:physiology*; D009119:Muscle Contraction / Q000187:drug effects; D009479:Neuropeptides / Q000494:pharmacology*; D009842:Oligopeptides / Q000494:pharmacology; D010539:Permeability / Q000187:drug effects; D011188:Potassium / Q000494:pharmacology; D015320:Tachykinins / Q000494:pharmacology; D014882:Water-Electrolyte Balance / Q000187:drug effects
D002121:Calcium Channel Blockers; D004232:Diuretics; D019476:Insect Proteins; D009479:Neuropeptides; D009842:Oligopeptides; D015320:Tachykinins; C068632:locustatachykinin III protein, insect; C074457:locustakinin; C011536:proctolin; D007444:Inulin; D011188:Potassium; D002118:Calcium