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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Primary monolayers grown from F1 band of a Percoll gradient centrifugation ("distal" monolayers) were studied, after confluency, 6-14 days after seeding. Transmission and scanning electron microscopy revealed that two cell types, resembling principal cells of the rabbit cortical collecting tubule (CCT) and intercalated cells of either CCT or connecting tubule, constitute approximately 96% of the monolayer. About two-thirds of the intercalated cells fluoresced when treated with fluorescent peanut lectin. Indirect specific immunocytofluorescent staining revealed fluorescence in 96% of the cells, confirming that the monolayers were derived from CCT or connecting tubule cells. Exposure of monolayers to vasopressin or isoproterenol increases adenosine 3',5'-cyclic monophosphate (cAMP) content in the cells and bathing medium, whereas parathyroid hormone was ineffective. Electrophysiological studies revealed a transepithelial voltage (VT) of -11 +/- 2 mV, and basolateral membrane voltage (Vb) of -77 +/- 5 mV (n = 20). The transepithelial electrical resistance (RT) was 1,870 +/- 250 omega X cm2 (n = 13). In three out of six monolayers, amiloride (10(-5) M) applied to the apical side produced an increase in apical membrane voltage (Va) from -71 +/- 1 to -89 +/- 9 mV) and a decrease in VT (from -10 +/- 1 to -2 +/- 1 mV). The RT did not change during amiloride exposure. Exposure of the apical membrane to 140 mM K+-depolarized Va from -67 +/- 7 to -39 +/- 11 mV (P less than 0.002) and hyperpolarized VT from -7 +/- 2 to -15 +/- 3 mV (P less than 0.005). Exposure to high K+ from the basolateral side depolarized Vb from -76 +/- 11 to -43 +/- 10 mV (P less than 0.001) and depolarized VT from -9 +/- to 8 +/- 5 mV (P less than 0.001). This preparation is suitable to study basic aspects of epithelial transport by electrophysiological methods and other techniques. The findings are consistent with several of the known properties of cortical collecting tubules from rabbits studied by the isolated perfused tubule technique.
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PMID:Electrophysiological studies of primary cultures of rabbit distal tubule cells. 303 77

We examined the electrophysiological and Na+ transport characteristics of rat papillary collecting duct (PCD) cells grown in primary cultures. Grown as monolayers on polycarbonate filters, the cells displayed similar morphological characteristics to native epithelia. They also bound Dolichus biflorus lectin, a property shared by native cells. Monolayers developed a peak electrical resistance of 100-200 omega.cm2 and a transmonolayer voltage of less than 2 mV. Similar values were measured in the perfused, native PCD of the same species as well as PCD cells cultured from rabbit and bovine kidneys. Hamster cells did not readily develop confluent monolayers under the same conditions. Exposure of the cultured cells to 10% fetal calf serum for 24 h caused the Na+ uptake across the apical membrane to double, an effect not reproduced by indomethacin, insulin, vasopressin, aldosterone, dexamethasone, or hexamethylene bisacetamide (an inducer of differentiation). Amiloride (1 mM) inhibited Na+ uptake by 50-80%. The measured short-circuit current did not correlate with Na+ uptake and was clearly dissociated by exposure to serum. The results suggest that there is more than one mechanism of ion transport by the rat PCD.
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PMID:Characteristics of papillary collecting duct cells in primary culture. 314 84

Rat renal papillary collecting duct (PCD) cells were isolated using collagenase and hyaluronidase digestion and a three-step low-speed centrifugation. As assessed by binding of the lectin Dolichos biflorus and determination of vasopressin-sensitive adenylate cyclase and Na+-K+-ATPase, the enrichment of PCD cells over a crude papillary cell preparation was 1.8, 2.4, and 1.4, respectively. Microscopic evaluation indicated that the preparation was greater than 90% pure PCD cells. The isolated cells were viable as evident from the high K/Na ratio of intracellular electrolytes measured by electron probe analysis (5.3), from the high ATP/ADP ratio (2.15), and the metabolic response to alterations in Na transport. Exposure to 2 mM ouabain or removal of Na reduced O2 consumption by 25-35%; the uncoupler carboxylcyanide-m-chlorophenylhydrazone more than doubled O2 consumption. In the presence of 14 mM glucose and at a PO2 of 100 Torr the cells produced substantial quantities of lactate. This aerobic glycolysis may account for greater than 20% of the ATP production. In the presence of rotenone, glycolysis increased by 56% and was able to maintain the cellular ATP level at 65% of control. In the absence of any exogenous substrate PCD cells respired normally and had a close to normal ATP content, but lactate production was markedly decreased. These results demonstrate that viable PCD cells can be isolated from rat kidney. At normal PO2 and in the presence of D-glucose the cells show a substantial amount of aerobic glycolysis, although their mitochondrial respiration is not rate limiting. In the absence of glucose the cells derive the majority of their energy from an as yet unidentified endogenous substrate.
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PMID:Purification of rat papillary collecting duct cells: functional and metabolic assessment. 330 74

Some reports suggest that the plasma membrane glycocalyx of collecting duct epithelial cells, as well as interstitial glycoconjugates, may be involved in vasopressin action and urinary concentration. In view of this, we have used the lectin-gold technique to map and quantify Helix pomatia lectin (HPL)-binding sites in the inner medulla of kidneys from normal Long-Evans rats, vasopressin-deficient Brattleboro rats, and Brattleboro rats treated for up to 5 wk with exogenous vasopressin. The results show that the labeling of epithelial cell plasma membranes from collecting ducts and thin limbs of Henle is not different between normal and Brattleboro rats, and the labeling is not modified by chronic vasopressin treatment. In contrast, the heavy interstitial labeling seen in normal rats is virtually absent from Brattleboro rats, but it is progressively restored by chronic vasopressin treatment of Brattleboro rats. These results show that vasopressin does not modify HPL-binding glycoconjugates on epithelial cell plasma membranes, but that vasopressin treatment has a major effect on HPL-binding glycoconjugates in the medullary interstitium.
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PMID:Lectin-gold labeling of glycoconjugates in normal and Brattleboro rat papilla: effect of vasopressin. 334 85

A noninvasive microscopic method was used to assess the cell specificity of vasopressin binding within the heterogeneous collecting duct. The binding of a fluorescent vasopressin analog (1-desamino-8-rhodamine-L-lysine vasopressin) to cells of the microperfused rabbit cortical collecting tubule was visualized and quantitated with image-intensified video microscopy and digital image processing. Binding to the basolateral membranes of a subpopulation of cells could be detected within 1-2 min of addition of the fluorescent analog (10 nM) to the peritubular bath. Binding could be prevented or reversed by the addition of a 10-fold excess of the native hormone, which indicates that the fluorescent analog binds specifically to vasopressin receptors. The time course of binding paralleled and slightly preceded hyperpolarization of the lumen-negative transepithelial voltage, an electrical response that is also elicited by the native hormone. Double-label experiments in which the intercalated cell population was stained with fluorescein-labeled peanut lectin revealed that binding of the vasopressin analog was localized to the remaining cell type, the principal cell. Our results support the following conclusions. First, the principal cell constitutes the primary target cell for vasopressin in the rabbit cortical collecting tubule, although the intercalated cell may possess a limited number of receptors at a density below the detection limit of this optical approach. Second, computer-enhanced video microscopy is a powerful, noninvasive method for assessing the kinetics and spatial pattern of hormone binding.
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PMID:Cell specificity of vasopressin binding in renal collecting duct: computer-enhanced imaging of a fluorescent hormone analog. 347 19

The lectin wheat germ agglutinin (WGA) elicited a prompt and sharp increase in intracellular Ca2+ concentration in human platelets. The WGA-induced Ca2+ mobilization was markedly inhibited by a protein kinase inhibitor staurosporine, whereas Ca2+ mobilization by receptor-mediated agonists, including thrombin, platelet-activating factor, and arginine-vasopressin, was not. In contrast, the lectin-induced Ca2+ mobilization was resistant to cyclic AMP inhibition, compared with that induced by receptor-mediated agonists. These findings indicate that the mechanism of intracellular Ca2+ mobilization, or possibly phospholipase C activation, induced by WGA is different from that induced by receptor-mediated agonists in human platelets.
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PMID:Wheat germ agglutinin-induced intracellular calcium mobilization in human platelets: suppression by staurosporine and resistance to cyclic AMP inhibition. 838 40

The present investigation was designed to investigate the fate of the large pool of neurohypophyseal hormones that is never released into the blood. Normal Sprague-Dawley and taiep mutant rats were investigated under normal water balance, after dehydration and after dehydration-rehydration. Lectin histochemistry and light- and electron-microscopic immunocytochemistry using antibodies against vasopressin, oxytocin, and neurophysins used at low (1:1,000) and high (1:15,000) dilutions allowed to distinguish (1) recently packed immature granules, as those located in the perikaryon; (2) mature; and (3) aged granules. The distribution of these granules within the different domains of the neurosecretory axons located in the neural lobe, namely, undilated segments, swellings, terminals, and Herring bodies, and the response of these compartments to dehydration and dehydration-rehydration allowed to roughly follow the routing of the granules through such axonal domains. It is suggested that granules may move backward and forward between the terminals and the swellings. At variance, aged granules located in Herring body are retained in this compartment and would finally become degraded. Herring bodies displayed distinct lectin binding and immunocytochemical properties, allowing to distinguish them from axonal swellings. After a dehydration-rehydration cycle, immunocytochemistry and electron microscopy revealed that Herring bodies were no longer present in the neural lobe and that several terminals had degenerated. It is concluded that (1) the neurophysin axons may undergo remodeling under appropriate stimuli and (2) Herring bodies are a specialized and plastic domain of the magnocellular neurosecretory neuron involved in the disposal of aged neurosecretory granules. No differences were detected at the neural lobe level between normal and mutant rats subjected to the same experimental conditions.
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PMID:The destination of the aged, nonreleasable neurohypophyseal peptides stored in the neural lobe is associated to the remodeling of the neurosecretory axon. 1635 85

The present study was done to determine whether the vasopressinergic neurons in the hypothalamus controlling flank marking behavior are distinct from the magnocellular neurons comprising the hypothalamo-neurohypophysial system. Animals were either hypophysectomized or injected with a suicide transport lectin, volkensin, into the neurohypophysis. Both procedures resulted in a pronounced loss of vasopressin-immunoreactive perikarya throughout the hypothalamus concomitant with increases in water intake and urine output and decreases in circulating levels of vasopressin. The loss of the hypothalamo-neurohypophysial system was most pronounced in volkensin-treated animals that presented with frank diabetes insipidus and exceedingly low levels of plasma vasopressin. However, the vasopressinergic fibers and magnocellular neurons in and around the anterior hypothalamus implicated in the control of flank marking survived the volkensin treatment. Volkensin-treated animals exhibited levels of flank marking typical of untreated animals. These data suggest the presence of anatomically and functionally distinct populations of vasopressinergic magnocellular neurons in the hypothalamus of the golden hamster.
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PMID:Functionally and anatomically distinct populations of vasopressinergic magnocellular neurons in the female golden hamster. 2155 97


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