Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.4.3 (phospholipase C)
 18,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Purinoceptor responses were analyzed in B10 cells, a clonal population of rat brain capillary endothelial cells. 2. B10 cells lack P2U receptors as evidenced by the lack of UTP responses and the failure to amplify P2U-related sequences by polymerase chain reaction. 3. B10 cells responded to adenine nucleotides by large increases in [Ca2+]i. Half maximum effective concentrations were 2-methylthio-ATP: 180 nM > 2-chloro-ATP: 310 nM = ADP: 330 nM > adenosine 5'-O-(3-thiotrisphosphate): 2.3 microM = ATP: 2.7 microM. The maximum response to ATP was only 55% of that to ADP while that to ATP derivatives was 75%. 4. The actions of adenine nucleotides were not associated with a measurable activation of phospholipase C. 5. Cross desensitizations of the actions of ADP and ATP were observed. 6. In additivity experiments, ADP superposed its action on top of that of ATP and ATP partially inhibited the action of ADP. 7. It is concluded that ATP acts as a partial agonist of the P2Y-like receptor of brain capillary endothelial cells.
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PMID:ATP, a partial agonist of atypical P2Y purinoceptors in rat brain microvascular endothelial cells. 758 45

Ischemia-reperfusion injury remains a major clinical problem in liver transplantation. One contributing factor is mitochondrial calcium (mCa(2+)) overload, which triggers apoptosis; calcium also regulates mitochondrial respiration and adenosine 5'-triphosphate (ATP) production. Recently, we reported the presence of purinergic P2Y(1)- and P2Y(2)-like receptor proteins in mitochondrial membranes. Herein, we present an evaluation of the functional characteristics of these receptors. In experiments with isolated mitochondria, specific P2Y(1) and P2Y(2) receptors ligands: 2-methylthio-adenosine 5'-diphosphate (2meSADP) and uridine 5'-triphosphate (UTP), respectively, were used, and mitochondrial calcium uptake was measured. 2meSADP and UTP had a maximum effect at concentrations in the range of the known P2Y(1) and P2Y(2) receptors. The P2Y inhibitor phosphate-6-azophenyl-2',4'-disulfonate (PPADS) blocked the effects of both ligands. The phospholipase C (PLC) antagonist U73122 inhibited the effect of both ligands while its inactive analog U73343 had no effect. These data strongly support the hypothesis that mitochondrial Ca(2+) uptake is regulated in part by adenine nucleotides via a P2Y-like receptor mechanism that involves mitochondrial PLC activation.
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PMID:Mitochondrial calcium transport is regulated by P2Y1- and P2Y2-like mitochondrial receptors. 1679 51