Glucose transport across the gill of the rainbow trout, Salmo gairdneri.
Glucose fluxes across the gills were measured in freshwater-adapted trout (Salmo gairdneri) using an in vitro, perfused-head preparation. A large asymmetry was observed for the primary lamellar pathway, glucose permeability in the serosa-to-mucosa direction being up to 24 times greater than the permeability in the mucosa-to-serosa direction. Chloride cells appeared to possess a maximal rate of transport, or TMG, of 79 mumol/hr per 100 g. Phlorizin, phloretin and, to a lesser extent, harmaline caused an increase in the rate of glucose efflux. The results suggest that the tubulo-vesicular reticulum, into which plasma is introduced under low pressure, may be regarded as a reabsorption site for glucose in a way similar to the nephron proximal tubule. Thus, essential molecules such as glucose are removed while excess or non-essential substances are excreted into the external medium.
D019325:3-O-Methylglucose; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002712:Chlorides / Q000378:metabolism; D005880:Gills / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D006246:Harmaline / Q000494:pharmacology; D008757:Methylglucosides / Q000494:pharmacology; D010693:Phloretin / Q000494:pharmacology; D010695:Phlorhizin / Q000494:pharmacology; D012487:Salmonidae / Q000378:metabolism*; D014337:Trout / Q000378:metabolism*
D002712:Chlorides; D008757:Methylglucosides; D019325:3-O-Methylglucose; D006246:Harmaline; D010695:Phlorhizin; D005947:Glucose; D010693:Phloretin