Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.1.1.148 (Thy1)
 1,210 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Extracellular adenine nucleotides are considered mediators of inflammation because they modulate functions of neutrophils and platelets. Until now, this role for adenine nucleotides has not been studied in vivo. In particular in the rat kidney, where ATP- and ADPase activity is present in the glomerular basement membrane, studies about the role of nucleotides may increase our understanding of the dynamics of glomerulonephritis (GN). Therefore, we examined effects of adenine derivatives ATP gamma S, ADP beta S and 2chloro-adenosine (2chloro-ADO) in vitro and during anti-Thy1 GN. The in vitro results show that ADP beta S and ATP gamma S are not degraded by glomerular nucleotidases but, on the other hand do stimulate O2- production of peritoneal exudate cells (PEC). In contrast, 2chloro-ADO significantly inhibits O2- production of peritoneal exudate cells. For in vivo studies rats were rendered nephritic by intravenous injection of monoclonal anti-Thy1 IgG (5 mg/kg body weight). Subsequently, rats were treated with saline (group 1, N = 10), 2chloro-ADO (group 2, N = 10), ADP beta S (group 3, N = 10) or ATP gamma S (group 4, N = 10). All analogs (10 mg/kg body weight) were administered both at t = 0 and t = 12 hour. After 24 hours, rats were sacrificed and kidneys were examined histochemically. In an additional group of nephritic rats (N = 5) proteinuria was studied after 2-chloro-ADO treatment. Results show increased intraglomerular platelet aggregation in nephritic rats treated with ADP beta S, whereas 2chloro-ADO inhibits aggregation significantly as compared with nephritic rats receiving saline. The percentage of granulocytes producing O2- is significantly increased in glomeruli after treatment of nephritic rats with ATP gamma S, whereas cell influx itself is not changed. In contrast, 2chloro-ADO inhibits intraglomerular O2- production, which is associated with the complete inhibition of proteinuria in the early phase of anti-Thy1 GN. These data demonstrate significant pro-inflammatory activities of extracellular adenine nucleotides during anti-Thy1 GN suggesting an anti-inflammatory role for glomerular ATP/ADPase, which in concert with 5' nucleotidase converts ATP and ADP to antiinflammatory ADO.
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PMID:Modulation of anti-Thy1 nephritis in the rat by adenine nucleotides. Evidence for an anti-inflammatory role for nucleotidases. 153 30

ATP has been identified as an excitatory neurotransmitter in both the CNS and peripheral nervous system; however, little is known about the functional properties of ATP-gated channels in central neurons. Here we used a culture preparation of the postnatal rat retina to test the responsiveness of identified retinal ganglion cells (RGCs) and putative amacrines to exogenous ATP and other purinoceptor agonists. Rapidly activating ATP-induced currents (IATP) were exclusively generated in a subpopulation (approximately 65%) of RGCs. The latter were identified by Thy1.1 immunostaining, repetitive firing patterns, and activation of glutamatergic autaptic currents. None of the putative amacrine cells was ATP-sensitive. IATP could be induced with ATP, ADP, and alpha,beta-mATP but not with adenosine. It was antagonized by suramin. The current-voltage relationship of IATP showed marked inward rectification. Dose-response analysis yielded an EC50 of 14.5 microM, with a Hill coefficient of 0.9. Noise analysis of IATP suggested a mean single channel conductance of 2.3 pS. Retinal P2X purinoceptor channels exhibited a high permeability for Ca2+. PCa/PCs obtained from reversal potentials of IATP under bi-ionic conditions amounted to 2. 2 +/- 0.7. In the majority of cells, the decay of IATP was biphasic. The degree of current inactivation during the first 2 sec of agonist application was highly variable. Heterogeneity was also found with respect to the sensitivity to ADP and alpha,beta-mATP and the blocking action of suramin, suggesting expression of multiple P2X receptor subtypes. Our results indicate that activation of P2X receptor channels represents an important pathway for Ca2+ influx in postnatal RGCs.
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PMID:Ca2+-permeable P2X receptor channels in cultured rat retinal ganglion cells. 1021 95

It has been demonstrated in anti-Thy1 glomerulonephritis that extracellular adenine nucleotides have a significant pro-inflammatory activity, however, glomerular ATP/ADPase, which in concert with 5'-nucleotidase converts ATP/ADP, and AMP to anti-inflammatory adenosine had an anti-inflammatory role. We have studied distribution of 5'-nucleotidase and divalent cation-activated ATPase in kidney biopsies of 15 patients with glomerulonephritis. The major finding was an overexpression of 5'-nucleotidase in the mesangium of kidney from patients with membranous nephropathy. No change in 5'-nucleotidase expression was observed in other common forms of glomerulonephritis: IgA nephropathy, mesangioproliferative and mesangiocapillary glomerulonephritis. The distribution of Mg(2+)-ATPase in investigated specimens was similar to control distribution. Results obtained in this study indicate increased mesangial expression of 5'-nucleotidase in non-proliferative form of glomerulonephritis consistent to a role of mesangial cells in inflammatory processes.
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PMID:Increased expression of glomerular mesangial cell 5'-nucleotidase in membranous nephropathy. 1218 7