Methylene Atp
Mostrando 13-24 de 118 artigos, teses e dissertações.
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13. Stimulation of the KATP channel by ADP and diazoxide requires nucleotide hydrolysis in mouse pancreatic beta-cells.
1. The mechanisms by which ADP and the hyperglycaemic compound diazoxide stimulate the activity of the ATP-regulated K+ channel (KATP channel) were studied using inside-out patches isolated from mouse pancreatic beta-cells maintained in tissue culture. 2. The ability of diazoxide and ADP to increase KATP channel activity declined with time following patch ex
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14. Release of adenosine, inosine and hypoxanthine from rabbit non-myelinated nerve fibres at rest and during activity.
The composition of the efflux from desheathed rabbit vagus nerve, loaded with radioactivity by incubation in [3H]adenosine, was studied at rest and during electrical activity and after application of inhibitors of ecto-enzymes and modifications of intermediary metabolism. In addition, the degradation of externally applied ATP and adenosine was examined. [3H]
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15. On the role, inactivation and origin of endogenous adenosine at the frog neuromuscular junction.
1. The effects of adenosine deaminase, inosine, alkylxanthines (8-phenyltheophylline (8-PT), theophylline and isobutylmethylxanthine (IBMX], dipyridamole, alpha, beta-methylene ADP (AOPCP) and ATP analogues (alpha, beta-methylene ATP and beta, gamma-methylene ATP) on evoked end-plate potentials (e.p.p.s) were investigated in innervated sartorius muscles of t
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16. Adenosine triphosphate-evoked currents in cultured neurones dissociated from rat parasympathetic cardiac ganglia.
1. The excitatory response of cultured neurones of rat parasympathetic cardiac ganglia to extracellular adenosine 5'-triphosphate (ATP) was examined using the whole-cell isolated membrane patch recording configurations of the patch clamp technique. The short latency between ATP application and activation of the membrane current (less than 20 ms) suggests a d
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17. Asymmetry of vascular responses of perfused rabbit carotid artery to intraluminal and abluminal vasoactive stimuli.
1. Responses of the carotid artery of rabbits to intraluminal and abluminal administration of purinergic agonists were examined. The carotid artery was perfused in vitro and changes in diameter were recorded. 2. Intraluminal acetylcholine, ADP, and ATP produced pronounced vasodilatation, whereas abluminal acetylcholine, but not ADP and ATP, produced dilatati
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18. Comparison between sympathetic adrenergic and purinergic transmission in the dog mesenteric artery.
1. Electrical transmural stimulation evoked a sympathetic contraction in the isolated dog mesenteric artery. This contraction consisted of adrenergic and purinergic components, which were separately observed under conditions where postjunctional P2 purinoceptors were desensitized with alpha, beta-methylene ATP or postjunctional alpha 1 adrenoceptors were blo
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19. Evidence for a role of pituitary ATP receptors in the regulation of pituitary function.
Despite a rapidly increasing acceptance for a role of ATP as an extracellular mediator in several biological systems, the present report shows that ATP may mediate physiological responses in pituitary cells. We have now been able to demonstrate a specific action of ATP receptors to mediate the release of luteinizing hormone from gonadotropes and have coupled
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20. Nucleoside triphosphate-dependent DNA-binding properties of mos protein.
We have previously shown that the mos gene product, p40mos, produced in Escherichia coli binds ATP and has ATPase activity. In the present study, we investigated the DNA-binding properties of p40mos and two mos deletion mutant proteins. Nitrocellulose blot protein-DNA binding assays showed that p40mos binds DNA in the presence of Mg2+-ATP and certain other n
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21. In vitro transcription catalyzed by heat-treated human rotavirus.
The in vitro characteristics of human rotavirus transcription have been examined. The virus has an associated RNA polymerase activity which was activated after a heat shock treatment. The enzyme required the presence of the four ribonucleoside triphosphates and a divalent cation (Mg2+), and it required an optimum pH of 8.5. The polymerase was activated by mo
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22. An ATP-sensitive conductance in single smooth muscle cells from the rat vas deferens.
1. The whole-cell voltage-clamp technique was used to study the effects of extracellular ATP on smooth muscle cells isolated from the rat vas deferens. 2. ATP (1-200 microM) elicited an inward-rectifying current that was rapid in onset (less than or equal to 100 ms), reached a peak value that depended on [ATP], and desensitized in the continued presence of A
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23. Ca2+ responses to ATP via purinoceptors in the early embryonic chick retina.
1. The action of adenosine triphosphate on cytoplasmic Ca2+ concentration ([Ca2+]i) was studied in the retinal cell of early embryonic chicks with fura-2 fluorescence measurements. The fluorescence was measured from the whole neural retina dissected from chick embryos at embryonic day three (E3). 2. Bath application of ATP (> or = 30 microM; EC50, 128 microM
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24. Mechanism of action of ATP on canine pulmonary vagal C fibre nerve terminals.
1. The effects of extracellular adenosine 5'-triphosphate (ATP) on pulmonary vagal afferent fibres (n = 46) was studied in a canine model in vivo (n = 38). 2. ATP (3-6 mumol kg-1), administered as a rapid bolus into the right atrium, elicited a transient burst of action potentials in cervical vagal fibres, which was not affected by either blockade of ganglio