Results 161 to 170 of about 2,507 (197)

Ecto-nucleotidases and Ecto-phosphatases from Leishmania and Trypanosoma Parasites

2013
Ecto-enzymes can be defined as membrane-bound proteins that have their active site facing the extracellular millieu. In trypanosomatids, the physiological roles of these enzymes remain to be completed elucidated; however, many important events have already been related to them, such as the survival of parasites during their complex life cycle and the ...
Anita Leocadio, Freitas-Mesquita, José Roberto, Meyer-Fernandes   +1 more
openaire   +2 more sources

Ecto‐nucleotidase activities in spinal cord of rats changes as function of age

International Journal of Developmental Neuroscience, 2003
AbstractAn increase in ADP hydrolysis was observed in spinal cord synaptosomal fractions of 2‐month‐old Wistar male rats, when compared to other ages (1, 4 and 6 months of age), while no change in ATPase activity was observed. Conversely, in female rats, whilst no change in ADPase activity was observed in the spinal cord synaptosomal fraction, ATPase ...
Iraci Lucena S, Torres, Ana Maria O, Battastini, Andréia, Buffon, Cristina Ribas, Fürstenau, Ionara, Siqueira, João J F, Sarkis, Carla, Dalmaz, Maria Beatriz C, Ferreira   +7 more
openaire   +2 more sources

The modulation of ecto-nucleotidase activities by glutamate in cultured cerebellar granule cells

NeuroReport, 2000
Several enzymes hydrolyze ATP, producing ADP which is hydrolyzed to AMP. Ecto-5'-nucleotidase produces adenosine from AMP. Glutamate (Glu) is an excitatory neurotransmitter and increases extracellular adenosine levels, which is considered an important inhibitory neuromodulator. Here we show that Glu activates ADP and AMP hydrolysis.
C R, Boeck, M J, Bronzatto, D G, Souza, J J, Sarkis, D, Vendite   +4 more
openaire   +2 more sources

BIOCHEMISTRY, LOCALIZATION AND FUNCTIONAL ROLES OF ECTO-NUCLEOTIDASES IN THE NERVOUS SYSTEM

Progress in Neurobiology, 1996
Nucleotides such as ATP, ADP, UTP or the diadenosine polyphosphates and possibly even NAD+ are extracellular signaling substances in the brain and in other tissues. Enzymes located on the cell surface catalyze the hydrolysis of these compounds and thus limit their spatio-temporal activity.
openaire   +2 more sources

Exercise training prevents ecto-nucleotidases alterations in platelets of hypertensive rats

Molecular and Cellular Biochemistry, 2012
In this study, we investigated the effect of 6 weeks of swimming training on the ecto-nucleotidase activities and platelet aggregation from rats that developed hypertension in response to oral administration of L-NAME. The rats were divided into four groups: control (n = 10), exercise (n = 10), L-NAME (n = 10), and exercise L-NAME (n = 10). The animals
Andréia Machado, Cardoso, Margarete Dulce, Bagatini, Caroline Curry, Martins, Fátima Hussein, Abdalla, Daniela, Zanini, Roberta, Schmatz, Jessié, Gutierres, Victor Camera, Pimentel, Gustavo, Thomé, Claudio Alberto Martins, Leal, Juliano Marchi, Vieira, Naiara, Stefanello, Fernando, da Silva Fiorin, Jucimara, Baldissareli, Luiz Fernando Freire, Royes, Adriane Bello, Klein, Vera Maria, Morsch, Maria Rosa Chitolina, Schetinger   +17 more
openaire   +2 more sources

Extracellular nucleotides regulate the expression and activity of ecto-nucleotidases by osteoblasts

Bone, 2010
Previous work has shown that extracellular nucleotides (>1 μM ATP/UTP) prevent bone nodule formation in vitro by blocking mineralisation of the collagenous matrix. The ratio of phosphate (Pi) to pyrophosphate (PPi) in the bone microenvironment is a fundamental regulator of mineralisation.
Isabel Orriss, Timothy Arnett
openaire   +1 more source

Habituation to an open field alters ecto-nucleotidase activities in rat hippocampal synaptosomes

Neuroscience Letters, 2007
ATP and adenosine may play a role in the mechanisms of synaptic plasticity and memory formation. Previous studies have shown that ecto-nucleotidase activities are altered during memory consolidation of an aversive task named step-down inhibitory avoidance. Here we investigate ecto-nucleotidase activities in hippocampal synaptosomes of rats submitted to
Eduardo Luiz, Pedrazza, Gustavo Pelicioli, Riboldi, Grace Schenatto, Pereira, Iván, Izquierdo, Carla Denise, Bonan   +4 more
openaire   +2 more sources

Ecto-nucleotidase of cultured rat superior cervical ganglia: dipyridamole is a novel inhibitor

European Journal of Pharmacology, 2000
Based on studies of agonist potencies on intact rat superior cervical ganglia, it has been suggested that this ganglion possesses distinct receptors for purine and pyrimidine nucleotides. However, the potency of an agonist is dependent upon whether it is susceptible to extracellular metabolism by the tissue.
Connolly, GP, Duley, JA
openaire   +4 more sources

Chronic treatment with lithium increases the ecto-nucleotidase activities in rat hippocampal synatosomes

Neuroscience Letters, 2004
Lithium is a mood-stabilizing treatment used in bipolar and other psychiatric disorders. The molecular mechanisms underlying lithium action remain poorly understood. Adenosine is a neuromodulator that possesses anticonvulsant and neuroprotective properties and the ecto-nucleotidase pathway is a metabolic source of the extracellular adenosine.
Leandre Carmem, Wilot, Rosane Silva, Da Silva, Otemar Júnior, Ferreira, Carla Denise, Bonan, João José Freitas, Sarkis, Elizabete, Rocha, Ana Maria Oliveira, Battastini   +6 more
openaire   +2 more sources

Reactive red 2: a P2y-selective purinoceptor antagonist and an inhibitor of ecto-nucleotidase

Naunyn-Schmiedeberg's Archives of Pharmacology, 1995
Effects of reactive red 2 and its parent compound acid red 33 were studied in rat vas deferens and guinea-pig taenia coli. In rat vas deferens, reactive red 2(1 to 10 microM) shifted the concentration-response curve for the P2X-purinoceptor-mediated contraction effect of alpha, beta-methylene ATP slightly to the right and progressively decreased the ...
R, Bültmann, K, Starke
openaire   +2 more sources