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)

The influence of antidiuretic hormone (ADH) and papaverine on hydroxyquinoline-induced nephropathy in rats was tested, using histotopochemistry, enzyme activity measurement and morphometric investigation. Hydroxyquinoline causes a marked increase in renal weight, the development of wedge-shaped foci with severely dilated tubule segments, and a simultaneous reduction in dehydrogenases, alkaline phosphatase, and alpha-naphthyl esterase. Both ADH and papaverine produced a significant inhibition of renal damage. The subjective findings were quantitatively confirmed by measurement of enzyme activity, using the microscope photometer, and by morphometric studies with the Leitz-Classimat (determination on the basis of the alkaline phosphatase reaction) of the surface percentage of brush border in the proximal tubules. A disturbance of the hairpin counter-current system is to be considered as the cause of the renal lesion. This disturbance is caused by hydroxyquinoline-induced impairment of Na+/K+ transport, especially in the thick ascending limb of Henle's loop. Our results show that the hydroxyquinoline nephropathy can be favourably influenced both by stimulation of water re-absorption and possibly also transepithelial Na+ transport (ADH), and by increasing the blood flow of the arteriolae rectae with a resultant lowering of the intratubular urine concentration (papaverine). The dependency of hydroxyquinoline nephropathy on the phylogenetically determined concentration capacity of the kidney, and the effective influencing of the condition by ADH and papaverine indicate the importance of the degree of efficiency of the medullary countercurrent system in the pathogenesis of this renal lesion.
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PMID:The significance of the hairpin counter-current principle in the pathogenesis of toxic kidney lesions. An investigation of the influence of antidiuretic hormone and papaverine on hydroxyquinoline nephropathy of the rat. 88 59

Endocrine abnormalities in patients with chronic renal failure are well documented. The present study aimed to assess the influence of long-term erythropoietin (EPO) therapy on endocrine abnormalities in haemodialyzed patients. Two groups of haemodialyzed patients, each of which comprised 17 subjects, were examined. The first one treated by EPO (EPO group) while the second one did not receive this hormone (NO-EPO group). A complete biochemical and hormonal check-up was performed before and at the 3, 6, 9 and 12 months of the study period. Normal values for the estimated parameters were obtained in appropriately selected sex and age-matched healthy subjects. After EPO therapy an increase of the haematocrit value from 21.8 +/- 0.9% to 32.6 +/- 0.9% was observed which was accompanied by a significant decline of plasma ferritin and saturation of transferrin. In patients of the NO-EPO group a significant although less marked rise of the haematocrit value (21.4 +/- 0.4% to 24.2 +/- 0.6%) was also noticed. EPO therapy did not change electrolytes (Na, K, Ca, inorganic phosphate), osteocalcin, creatinine, glucose and alkaline phosphatase plasma levels as well as plasma concentrations of calcium related hormones (PTH, calcitonin, 1.25(OH)2D3) and vasopressin (AVP). EPO treatment induced a significant decline of somatotropin (HGH), prolactin (PRO), follitropin (FSH), lutropin (LH), ACTH, cortisol, plasma renin activity, aldosterone, insulin (IRI), glucagon (IR-G), pancreatic polypeptide (PP) and gastrin plasma levels and an increase of plasma estradiol, testosterone and atrial natriuretic peptide (ANP). These EPO induced endocrine alterations were restricted mostly to the first 6 months of EPO administration.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Influence of long-term erythropoietin therapy on endocrine abnormalities in haemodialyzed patients. 145 6

Levels of the G-protein alpha-subunits alpha-Gi-2, alpha-Gi-3 and the 42 kDa, form of alpha-Gs were markedly decreased in hepatocyte membranes from streptozotocin-diabetic animals as compared with normals. In contrast, no detectable changes in alpha-Gi subunits were seen in liver plasma membranes of streptozotocin-diabetic animals, although levels of the 45 kDa form of Gs were increased. G-protein beta subunits in plasma membranes were unaffected by diabetes induction. Analysis of whole-liver RNA indicated that the induction of diabetes had little effect on transcript levels of Gi-3, caused an increase in Gs transcripts and decreased transcript number for Gi-2, albeit to a much lesser extent than was observed upon analysis of hepatocyte RNA. In both hepatocyte and liver plasma membranes, immunoblot analysis showed that levels of the catalytic unit of adenylate cyclase were increased upon induction of diabetes. Under basal conditions, alpha-Gi-2 from hepatocytes of diabetic animals was found to be both phosphorylated to a greater extent than alpha-Gi-2 isolated from hepatocytes of normal animals, and furthermore was resistant to any further phosphorylation upon challenge of hepatocytes with angiotensin, vasopressin or the phorbol ester 12-O-tetradecanoylphorbol 13-acetate. Treatment of isolated plasma membranes from normal, but not diabetic, animals with purified protein kinase C caused the phosphorylation of alpha-Gi-2. Treatment of membranes from diabetic animals with alkaline phosphatase caused the dephosphorylation of alpha-Gi-2 and rendered it susceptible to subsequent phosphorylation with protein kinase C. Low concentrations of the non-hydrolysable GTP analogue guanylyl 5'-imidodiphosphate inhibited adenylate cyclase activity in both hepatocyte and liver plasma membranes from normal, but not diabetic, animals.
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PMID:Diabetes-induced alterations in the expression, functioning and phosphorylation state of the inhibitory guanine nucleotide regulatory protein Gi-2 in hepatocytes. 170 Jul

The effects of infusion of arginine vasopressin (20 mU.kg-1.min-1) on coronary blood flow and the proportion of the coronary microvasculature perfused was studied in rabbit myocardium. Fluorescein isothiocyanate--dextran was injected into anesthetized open-chest rabbits to identify the perfused vessels and an alkaline phosphatase stain was employed to locate the total microvasculature. Coronary blood flow (radioactive microspheres) was studied in separate groups of rabbits. Vasopressin infusion caused bradycardia (243 +/- 19 to 165 +/- 22 beats/min, mean +/- SD) and an increase in mean blood pressure (92 +/- 18 to 104 +/- 12 mmHg) (1 mmHg = 133.32 Pa). Coronary blood flow decreased significantly with vasopressin from 209 +/- 68 to 97 +/- 36 mL.min-1.100 g-1. The proportion of the arteriolar bed per millimeter squared perfused decreased significantly after vasopressin from 54 +/- 13 to 44 +/- 21%, while the percentage of capillaries per millimeter squared increased significantly from 57 +/- 6 to 67 +/- 11%. There were no subepicardial versus subendocardial differences in any measured parameter. Thus, both coronary blood flow and the proportion of the arteriolar bed perfused decreased with vasopressin. However, compensation occurred in that the proportion of capillaries perfused increased. This indicated an independent level of control of the coronary arteriolar and capillary beds. These microvascular changes may help to maintain oxygen supply-demand balance with vasopressin in the heart.
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PMID:Effect of vasopressin on myocardial capillary recruitment and coronary blood flow in the anesthetized rabbit. 171 7

We present here a method enabling the simultaneous detection of two messenger RNAs in tissue sections by use of a two-step in situ hybridization procedure. Tissue sections were hybridized with a radioactive probe and coated with emulsion. The emulsion was processed for development, fixed, and a second hybridization was performed through the emulsion with a biotinylated probe subsequently revealed with streptavidin-alkaline phosphatase. This procedure allows the detection of two mRNAs without loss of signal, removal of the emulsion, or spurious reaction. The simultaneous detection of oxytocin and vasopressin mRNAs in the hypothalamus, and of dopamine receptor and neuropeptide mRNAs in the striatum, demonstrated the efficiency of the procedure. Such a two-step procedure provides a simple and flexible way to make possible comparative analysis of the localization of two mRNAs within the same tissue section.
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PMID:Simultaneous detection of two messenger RNAs in the central nervous system: a simple two-step in situ hybridization procedure using a combination of radioactive and non-radioactive probes. 191 32

1. The use of radioactive and biotinylated oligonucleotide probes has been optimized to detect and analyze by in situ hybridization, neurons expressing neuropeptide genes (vasopressin, oxytocin, somatostatin). 2. In situ hybridization was performed on cryostat-cut sections obtained from tissues perfused with 1% formaldehyde. Radioactive probes were labeled by tailing with 35S-dATP and revealed with autoradiography. Biotinylated probes were obtained either by the incorporation of 11-biotin dUTP or by the addition of biotinylated nucleotides to the oligonucleotide during its synthesis. Biotin was revealed with streptavidin alkaline phosphatase and the appropriate substrate. 3. In the adult rat brain, radioactive and biotinylated probes revealed peptidergic neurons. The biotinylated probes provided an optimal cellular and subcellular resolution with a sensitivity similar to that observed with radioactive probes. Staining was selectively restricted to the cytoplasm and to the proximal part of processes. 4. Biotinylated vasopressin probes with 10 biotins added demonstrated magnocellular neurons and parvocellular neurons in the suprachiasmatic nucleus and the bed nucleus stria terminalis. 5. Vasopressin gene expression was studied during ontogeny in the rat fetus and neonate. Vasopressin mRNA was first detectable at gestational day 16 in the supraoptic nucleus in neurons of neuroblastic appearance. An aspect similar to the one present in adult was found at gestational day 19 in magnocellular neurons and at day 3 postnatal in parvocellular neurons. 6. The results confirm that radioactive oligonucleotide probes are efficient tools to investigate neuropeptide gene expression by in situ hybridization and demonstrate that biotinylated oligonucleotides are very efficient and provide a much higher resolution than radioactive probes with a reasonable sensitivity.
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PMID:Topography and ontogeny of the neurons expressing vasopressin, oxytocin, and somatostatin genes in the rat brain: an analysis using radioactive and biotinylated oligonucleotides. 197 Jul 59

Treatment of intact, 32Pi-labelled hepatocytes from lean Zucker rats with a range of agents including 12-O-tetradecanoyl-phorbol 13-acetate (TPA), vasopressin, and angiotensin II elicited substantial increases in the phosphorylation of the alpha-subunit of the inhibitory G protein of adenylate cyclase (alpha Gi-2). These agonist-induced phosphorylations of alpha Gi-2 were associated with loss of Gi function as assessed by the ability of low concentrations of guanylyl 5'-[beta,gamma imido]triphosphate (p[NH]ppG) to inhibit forskolin-stimulated adenylate cyclase activity. Hepatocytes from obese Zucker rats displayed a resistance to both agonist-induced phosphorylation of alpha Gi-2 and to p[NH]ppG-mediated inhibition of adenylate cyclase. The basal level of alpha Gi-2 phosphorylation in hepatocytes from obese Zucker rats was considerably greater at 1.06 +/- 0.09 mol phosphate/mol alpha Gi-2 than in hepatocytes from lean animals which gave 0.54 +/- 0.09 mol phosphate/mol alpha Gi-2. Incubation with TPA (10 ng/ml, 15 min) approximately doubled the level of phosphorylation of alpha Gi-2 in the hepatocytes from lean animals but had little effect on the phosphorylation of alpha Gi-2 in hepatocytes from obese animals. Incubation of hepatocytes from lean animals with ligands which lead to the phosphorylation of alpha Gi-2 abolished the ability of low concentrations of p[NH]ppG to inhibit adenylate cyclase expressed in isolated membranes. Treatment of hepatocyte plasma membranes from lean but not obese Zucker rats with pure protein kinase C led to the phosphorylation of alpha Gi-2. The resistance to protein-kinase-C-mediated phosphorylation in hepatocyte membranes from obese animals could be overcome by treatment of the membranes with alkaline phosphatase. These results indicate that the defect in guanine-nucleotide-mediated 'Gi function' seen in obese Zucker rats may be due to an inactivating phosphorylation of alpha Gi-2.
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PMID:Changes in the phosphorylation state of the inhibitory guanine-nucleotide-binding protein Gi-2 in hepatocytes from lean (Fa/Fa) and obese (fa/fa) Zucker rats. 212 55

Freshly isolated rabbit proximal tubules (PT), confluent primary rabbit proximal tubule cultures (PTC) and LLC-PK1 cells were characterised. Brushborder enzyme activities were lower in PTC than in LLC-PK1: ratios were 0.026 for alkaline phosphatase (AP), 0.458 for alanine aminopeptidase (AAP) and 0.514 for gamma-glutamyl transpeptidase (GGT). PT/PTC ratios were 79.7 for AP, 7.96 for AAP and 3.45 for GGT. Specific activities of hexokinase (HK) and lactate dehydrogenase (LDH) were high in cultured cells as compared to PT: PT/PTC ratios were 0.063 and 0.033, while PTC/LLC-PK1 ratios were 0.406 and 1.19 for HK and LDH respectively. PTC/LLC-PK1 ratios were 2.21 for Na/K ATPase, 2.07 for succinate dehydrogenase, 1.12 for cathepsin B, 0.607 for N-acetyl-beta-D-glucosaminidase and 8.98 for glutathione-S-transferase. Adenylate cyclase response to parathormone (PTH), was similar in PTC and PT, but stimulated/basal ratios were higher in PT than in PTC. LLC-PK1 cells were stimulated by thyrocalcitonin (SCT), arginin-vasopressin (AVP) and PTH; stimulated/basal ratios ranked AVP greater than PTH greater than SCT. Differences between both types of cultures affect the choice of in vitro model for nephrotoxicity studies.
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PMID:Adenylate cyclase responses and biochemical characterization of primary rabbit proximal tubular cell cultures and LLC-PK1 cells. 228 70

Human polycystic kidney disease (PKD) epithelia were successfully grown in culture and expressed abnormal characteristics. Cysts lining epithelia of superficial and deep cysts were microdissected and compared to individual normal human proximal straight tubules (PST) and cortical collecting tubules (CCT) grown in defined media. PKD cyst epithelia differed from normal renal tubular epithelia in growth patterns and structural and functional properties. PKD epithelia grew more rapidly and showed cyst-like areas in otherwise confluent monolayers. Polygonal and elongate cells contained an epithelial-specific cytokeratin antigen and had polarized morphology. An extremely abnormal basement membrane morphology was seen and consisted of some banded collagen and numerous unique blebs or spheroids. These blebs were apparently extruded from intracellular vacuoles and stained with ruthenium red, suggesting a proteoglycan component. Cytochemistry of marker enzymes demonstrated the presence of NaK-ATPase and alkaline phosphatase, but a lack of gamma-glutamyl transpeptidase. The response of adenylate cyclase activity to vasopressin, parathyroid hormone, and forskolin was significantly diminished in PKD cells as compared to PST and CCT. These studies suggest a defect in cell growth and basement membrane synthesis in human PKD. Cultured PKD epithelia provide a new tool for the study of the pathogenesis of this disease.
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PMID:A new method for studying human polycystic kidney disease epithelia in culture. 243 Nov 89

Proximal tubules were prepared from rat kidney cortex by collagenase digestion and purified by Percoll gradient centrifugation. Their enrichment was estimated by comparing the specific activities of various cell-specific enzymes in homogenates of renal cortex and of the isolated tubules. The tubules were cultured in a 50:50 mixture of Dulbecco's modified Eagle's and Ham's F12 media supplemented with insulin, transferrin, epidermal growth factor, hydrocortisone, and prostaglandin E1. After 2 to 3 d an extensive outgrowth of epithelial cells developed from the attached tubules. After 5 to 7 d near confluent monolayers were obtained. Hormonal responsiveness, marker enzyme activities, and transport properties were determined to further characterize the primary cultures. The cultured cells exhibited increased cyclic AMP production in response to parathyroid hormone but not calcitonin or vasopressin, consistent with the absence of cells derived from distal and collecting tubules. The cells also retained significant levels of 25-hydroxyvitamin D3-1 alpha-hydroxylase, alkaline phosphatase, and gamma-glytamyl-transpeptidase, three enzymes that are primarily associated with the proximal tubule. The cultured epithelial cells also exhibit a Na+-dependent phosphate and glucose transport systems. Therefore, the cells retain many functional properties that are characteristic of proximal tubules. Thus, the primary cultures should be suitable for the study of processes that occur specifically within this segment of the rat nephron.
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PMID:Characterization of primary cell cultures derived from rat renal proximal tubules. 254 89


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