Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

MDCK cells accumulate organic osmolytes in response to hyperosmotic NaCl-supplemented medium. We examined time course and inhibitor sensitivity of myo-inositol, sorbitol, and glycerophosphorylcholine (GPC) accumulation in MDCK cells exposed to hyperosmotic NaCl-, D-glucose-, or mannitol-supplemented media. In NaCl medium, cells preferentially accumulated inositol and GPC. In comparison, in glucose medium cells preferentially accumulated sorbitol and GPC. Inositol demonstrated a late (72-96 h) accumulation in glucose medium, although less than in NaCl medium. Mannitol medium did not significantly stimulate accumulation of any of these three osmolytes at 24 h, suggesting that hyperosmolality alone is not sufficient stimulus for their accumulation in this time frame. GPC accumulation was very rapid in glucose medium, and fell to the level induced by NaCl medium at 96 h (approximately 50 nmol/mg protein). Inositol and sorbitol accumulated more gradually, each reaching greater than 400 nmol/mg protein after 96 h. Sorbitol was still accumulating at 96 h, whereas inositol plateaued at 72-96 h. Phlorizin or sorbinil blocked accumulation of inositol or sorbitol, respectively. Sorbitol and GPC accumulation in glucose medium were partially inhibited in absence of serum or in presence of 1 microM vasopressin. Thus NaCl and glucose appear to stimulate specific cellular mechanisms responsible for accumulation of inositol, sorbitol, and GPC in MDCK cells. This accumulation is also modulated by constituents of serum.
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PMID:Modulation of osmolytes in MDCK cells by solutes, inhibitors, and vasopressin. 222 Nov 3

Three clones of the pig kidney cell line LLC-PK1 were isolated and characterized with regard to morphology, growth, proximal tubule enzyme activity, sugar uptake capacity, and hormone and drug responsiveness in a defined medium. Clone N4 was similar in morphology to the wild type (WT), whereas clone F8 showed loose attachment to the substrate, formed large, sweeping domes, and had an elongated desmosome junction between cells. The third clone, F2, did not form domes and showed a marked reduction in growth rate. Cultures of WT, N4, and F8 had higher specific activities of the enzyme alkaline phosphatase and gamma-glutamyl transpeptidase at confluence relative to growing cells; however, there was no evidence of an increase in activity of either enzyme at confluence in F2. Phlorizin-sensitive alpha-methyl-D-glucoside uptake and cytochalasin B-sensitive 2-deoxy-D-glucose uptake were measured in confluent cultures grown on porous filter supports. None of the clones lacked either of the hexose transport systems, although quantitative differences were evident. N4 cells grown in a defined medium in 96-well culture plates were tested in situ for their enzyme responses to differentiation inducers, tumor promoters, and hormones. Alkaline phosphatase activity was significantly increased at confluence by serum, parathyroid hormone (PTH), and vasopressin (AVP), and was decreased by tetradecanoylphorbol acetate (TPA) and epinephrine (EPI). Glutamyl transpeptidase activity was decreased at confluence by serum, TPA, and EPI. Similar tests on alpha-methyl-D-glucoside uptake showed that serum, TPA, PTH, and AVP had no significant effect on phlorizin-sensitive uptake; however, calcitonin increased uptake by 84% (n = 18). It was concluded that LLC-PK1 clones maintained in a defined medium are useful models for studying renal cell function.
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PMID:Growth, enzyme activity, sugar transport, and hormone supplement responses in cells cloned from a pig kidney cell line LLC-PK1. 256 38

Renal excretion of urea was assessed in adult and larval Ambystoma tigrinum by comparing simultaneous clearances of urea and inulin. The mean adult urea clearance ratio (CU/CIn) was 0.70 +/- 0.08 indicating net urea absorption. Larvae yielded a mean CU/CIn of 0.92 +/- 0.04. Individual larvae were quite variable however as approximately 30% displayed CU/CIn > 1. There was a significant negative correlation between CU/CIn and fractional water reabsorption. Comparisons of larval kidney urea concentration (KU) and plasma urea concentration (PU) revealed a mean KU/PU of 1.43 +/- 0.15. Treatment with 2,4-dinitrophenol decreased larval CU/CIn to 0.80 +/- 0.05 and KU/PU to 0.91 +/- 0.08. Phloridzin also decreased CU/CIn (0.67 +/- 0.06) however para-aminohippuric acid had no effect. Hypophysectomy combined with cautery of the pituitary stalk resulted in CU/CIn of 1.71 +/- 0.33 as compared to 0.84 +/- 0.08 in shams. These results are consistent with the possibility of net urea secretion at some point in the A. tigrinum nephron, followed by passive reabsorption in the distal segments under the influence of antidiuretic hormone.
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PMID:Renal excretion of urea in the salamander, Ambystoma tigrinum. 746 70