Much of the knowledge of pteridine biosynthesis from purines has come from radioactive tracer studies with whole organisms. Reports on the incorporation of the radioactivity of labeled precursors of purines (1) and of uniformly labeled adenine-1% (2) into riboflavin indicated the utilization of purines for riboflavin synthesis. Furthermore, the results of studies (2, 3) with adenine-814C showed...

In a previous communication (1) it has been shown that the accumulation of 4-aminoimidazole-5-carboxamide (“amine”) in sulfadiazine-inhibited Escherichia coli is suppressed by the addition of methionine and catalytic quantities of p-aminobenzoic acid (PABA), and it was assumed that the “labile methyl” group of the sulfur-containing amino acid is used, with the help of PABA as carrier, for the c...

ATP and adenosine are purines that play dual roles in cell metabolism and neuronal signaling. Acting at the A(1) receptor (A(1)R) subtype, adenosine acts directly on neurons to inhibit excitability and is a powerful endogenous neuroprotective and anticonvulsant molecule. Previous research showed an increase in ATP and other cell energy parameters when an animal is administered a ketogenic diet,...

A novel application of microdialysis was studied, in which myocardial outflow of amino acids and purines was monitored by intravasal microdialysis in the myocardial venous outflow during ischemia and reperfusion. Microdialysis catheters were introduced into the great cardiac vein, pulmonary artery, and external jugular vein in 20 anesthetized pigs. The left anterior descending artery was occlud...

El sector porcino en España representa el 14% de la producción total agraria, siendo un gran importancia economía nacional. Pero las explotaciones ganadería intensiva suponen riesgo para salud pública y medio ambiente. Las pérdidas nitratos por lixiviación provenientes del vertido purines a aguas superficiales subterráneas se han convertido grave problema medioambiental actualidad. En este trab...

Purines were long thought to be restricted to the intracellular compartment, where they are used for energy transactions, nucleic acid synthesis, and amultiplicity of biochemical reactions. However, it is now clear that both adenosine and adenosine triphosphate are (i) abundant biochemical components of the tumor microenvironment, (ii) potent modulators of immune cell responses and cytokine rel...