GIBBS, A.G.*; MARRON, M.T.; KAIN, K.J.; ALTHOFF, L.: Mechanisms of water conservation in desert Drosophila. Cactophilic fruitflies from the Sonoran Desert lose water much less rapidly than mesic species. Water is lost by three routes: excretion, cuticular transpiration, and respiration through the spiracles. Excretory losses comprised ~1% of total water loss and did not differ […]

FOLK, D.G.*; BRADLEY, T.J.: Ion Regulation and Water Balance in Drosophila melanogaster Selected for Enhanced Desiccation-Tolerance We are examining physiological processes associated with increased resistance to desiccation in five, replicate populations of Drosophila melanogaster that have undergone laboratory selection for enhanced desiccation-tolerance. For each population of desiccation-resistant flies (D populations), we have maintained a control […]

LI, T.*; ROER, R.D.: Gill Na+, K+-ATPase activity as a function of size and salinity in the blue crab, Callinectes sapidus Juvenile blue crabs (< 25mm carapace width) are found in large numbers in the oligohaline regions of the Cape Fear estuary. Previous work has shown that the juveniles lose Na to the dilute medium […]

FIESS, J.C.*; HUDSON, H.A.; HOM, J.R.; KATO, C.; YANCEY, P.H.: Depth correlations of organic osmolytes in foot and mantle tissues of vesicomyid bivalves Osmoconforming invertebrates such as bivalves use organic osmolytes such as free amino acids to maintain cell volume against the osmotic pressure of seawater. Recent studies have demonstrated that certain osmolytes can also […]

DUDAS, P.L.*; BRAUN, E.J.; PARKER, S.L.; RENFRO, J.L.: Urate Transport by Chick (Gallus gallus) Renal Proximal Tubule Epithelium Birds excrete uric acid (UA) as the major excretory end product of nitrogen metabolism. Others have shown that the renal proximal tubule is the site of UA secretion. In chickens transport of UA across the proximal tubule […]

MCWHORTER, T.J.*; MARTINEZ DEL RIO, C.; PINSHOW, B.: Osmoregulation in avian nectarivores – an integrative approach Nectar-feeding birds must often deal with large ingested water loads in order to meet their energetic demands. We investigated the importance of the integration of digestive and renal function for maintaining water homeostasis in these animals. We compared the […]

PIERMARINI, P.M.*; VERLANDER-REED, J.V.; ROYAUX, I.E.; EVANS, D.H.: Immunochemical Evidence for Pendrin in the Gills of the Euryhaline Atlantic Stingray (Dasyatis sabina): Implications for Ionic and Acid/Base Regulation Pendrin is recognized as an important Cl–/HCO3– exchanger in the mammalian kidney. This transporter has been localized in the apical membrane of B-type intercalated cells, which are […]

GOLDSTEIN, J; HOFF, K; HILLYARD, S: Effects of angiotensin II and hydration state on water absorption behavior of toads (Bufo punctatus) Anuran amphibians press their ventral skin to moist surfaces to facilitate osmotic water uptake, a process termed cutaneous drinking. The frequency and duration of two cutaneous drinking behaviors (the water absorption response, WR and […]

HIROI, J.*; MCCORMICK, S.D.: Effect of salinity on Na,K-ATPase and Na,K,2Cl-cotransporter in three salmonids with varying degrees of salinity tolerance Chloride cells in the gills of teleosts are the major site of ionic regulation. We compared seawater tolerance and chloride cell morphology of three salmonids, lake trout, brook trout and smolt of Atlantic salmon. Three […]

PELIS, R.M. *; RENFRO, J.L.: Active Sulfate Secretion by the Intestinal Epithelium of Winter Flounder is through Anion Exchange for Chloride Marine teleosts are hypoosmotic to their surrounding environment and must continuously drink seawater to avoid dehydration. It is widely accepted that net absorption of monovalent ions (sodium and chloride) occurs across teleost intestinal epithelial […]