guanosine-diphosphate and 6-(4-nitrobenzylthio)guanosine

guanosine-diphosphate has been researched along with 6-(4-nitrobenzylthio)guanosine* in 1 studies

Other Studies

1 other study(ies) available for guanosine-diphosphate and 6-(4-nitrobenzylthio)guanosine

Article	Year
Activation of A(3) receptors by endogenous adenosine inhibits synaptic transmission during hypoxia in rat cortical neurons. Restorative neurology and neuroscience, 2003, Volume: 21, Issue:1-2 The aim of our study was to characterize the influence of A(3) receptors on synaptic potentials (PSPs) in pyramidal cells from the rat cingulate cortex during hypoxia.. Intracellular recordings (n=49) were taken from slice preparations. PSPs were evoked by electrical stimulation.. Hypoxia (95%N(2)-5%CO(2), 5 min) reduced the amplitude of the PSPs significantly. The effect was more pronounced in the presence of adenosine re-uptake inhibitor S-(p-nitrobenzyl)-6-thioguanosine (NBTG) and deaminase inhibitor erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA); the effect was completely reversed by bovine adenosine deaminase. Hypoxic inhibition induced after A(1) receptor blockade with 1,3-dipropyl-8-cyclopentylxanthine (DPCPX) in the presence of NBTG was completely reversed by the A(3) antagonist 9-chloro-2-(2-furanyl)-5-[(phenylacetyl)amino]-1,2,4-triazolo[1,5-c]quinazoline (MRS 1220), indicating the involvement of A(3) receptors in hypoxic PSP inhibition. This was confirmed by A(3) agonist N(6)-(3-iodobenzyl)-adenosine-5'-N-methylcarboxamide (IB-MECA) inhibiting PSPs. The effect of IB-MECA was blocked by the rat A(3) receptor-selective antagonist 3-propyl-6-ethyl-5-[(ethylthio)carbonyl]-2-phenyl-4-propyl-3-pyridinecarboxylate (MRS 1523) and was not observed in the presence of G-protein inhibitor guanosine-5'-O-2-thiodiphosphate (GDP-beta-S).. We conclude that a high level of endogenous adenosine, which occurs during hypoxia, activates A(3) receptors. Their activation contributes to PSP inhibition by adenosine during hypoxia. Topics: Adenine; Adenosine; Animals; Cell Hypoxia; Cerebral Cortex; Drug Interactions; Electric Stimulation; Enzyme Inhibitors; Excitatory Postsynaptic Potentials; Guanosine; Guanosine Diphosphate; In Vitro Techniques; Male; Neurotransmitter Uptake Inhibitors; Purinergic P1 Receptor Agonists; Purinergic P1 Receptor Antagonists; Pyramidal Cells; Rats; Rats, Wistar; Receptor, Adenosine A3; Receptors, Purinergic P1; Synaptic Transmission; Thionucleosides; Thionucleotides; Time Factors	2003

Article

Year

Activation of A(3) receptors by endogenous adenosine inhibits synaptic transmission during hypoxia in rat cortical neurons.

Restorative neurology and neuroscience, 2003, Volume: 21, Issue:1-2

The aim of our study was to characterize the influence of A(3) receptors on synaptic potentials (PSPs) in pyramidal cells from the rat cingulate cortex during hypoxia.. Intracellular recordings (n=49) were taken from slice preparations. PSPs were evoked by electrical stimulation.. Hypoxia (95%N(2)-5%CO(2), 5 min) reduced the amplitude of the PSPs significantly. The effect was more pronounced in the presence of adenosine re-uptake inhibitor S-(p-nitrobenzyl)-6-thioguanosine (NBTG) and deaminase inhibitor erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA); the effect was completely reversed by bovine adenosine deaminase. Hypoxic inhibition induced after A(1) receptor blockade with 1,3-dipropyl-8-cyclopentylxanthine (DPCPX) in the presence of NBTG was completely reversed by the A(3) antagonist 9-chloro-2-(2-furanyl)-5-[(phenylacetyl)amino]-1,2,4-triazolo[1,5-c]quinazoline (MRS 1220), indicating the involvement of A(3) receptors in hypoxic PSP inhibition. This was confirmed by A(3) agonist N(6)-(3-iodobenzyl)-adenosine-5'-N-methylcarboxamide (IB-MECA) inhibiting PSPs. The effect of IB-MECA was blocked by the rat A(3) receptor-selective antagonist 3-propyl-6-ethyl-5-[(ethylthio)carbonyl]-2-phenyl-4-propyl-3-pyridinecarboxylate (MRS 1523) and was not observed in the presence of G-protein inhibitor guanosine-5'-O-2-thiodiphosphate (GDP-beta-S).. We conclude that a high level of endogenous adenosine, which occurs during hypoxia, activates A(3) receptors. Their activation contributes to PSP inhibition by adenosine during hypoxia.

Topics: Adenine; Adenosine; Animals; Cell Hypoxia; Cerebral Cortex; Drug Interactions; Electric Stimulation; Enzyme Inhibitors; Excitatory Postsynaptic Potentials; Guanosine; Guanosine Diphosphate; In Vitro Techniques; Male; Neurotransmitter Uptake Inhibitors; Purinergic P1 Receptor Agonists; Purinergic P1 Receptor Antagonists; Pyramidal Cells; Rats; Rats, Wistar; Receptor, Adenosine A3; Receptors, Purinergic P1; Synaptic Transmission; Thionucleosides; Thionucleotides; Time Factors

2003