Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.6.1.2 (alanine aminotransferase)
 26,722 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Theophylline administration to seven healthy male volunteers resulted in a rapid and significant decline in both plasma and erythrocyte pyridoxal-5'-phosphate levels. Total erythrocyte pyridoxal kinase levels increased during 15 wk of theophylline treatment from a mean initial activity of 19.23 +/- 5.03 (mean +/- SD) to 62.64 +/- 11.59 nmol pyridoxal-5'-phosphate formed/(g hemoglobin.h). Although plasma pyridoxal levels remained normal, the threefold increase in total erythrocyte pyridoxal kinase activity levels did not normalize plasma and erythrocyte pyridoxal-5'-phosphate levels. Pyridoxal-5'-phosphate hydrolysis was not affected by theophylline therapy. Increased pyridoxal oxidation was confirmed by elevated urinary 4-pyridoxic acid excretion after 15 wk of theophylline treatment. Mean erythrocyte alanine aminotransferase activity declined by 70%, and aspartate aminotransferase activity declined by 50%, indicating that decreased availability of pyridoxal-5'-phosphate can have widespread metabolic consequences. We conclude that the effect of theophylline on vitamin B-6 metabolism is not transitory and cannot be overcome by elevated intracellular levels of pyridoxal kinase. However, pyridoxine supplementation (10 mg/d for 1 wk) normalized indices of vitamin B-6 status and reversed the downward trend in both alanine aminotransferase and aspartate aminotransferase activity levels.
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PMID:Relationship between vitamin B-6 status and elevated pyridoxal kinase levels induced by theophylline therapy in humans. 223 Oct 24

Pyridoxal enzymes of transamination (aspartate aminotransferase, KF 2.6.1.1. and alanine aminotransferase, KF 2.6.1.2) have been studied for their activity in different departments of the rabbit brain under the effect of ionizing radiation and introduction of pyridoxal phosphate. It has been established that the effect of ionizing radiations does not evoke the change in aspartate aminotransferase and alanine aminotransferase activity in different structure-functional departments of the rabbit brain, the decrease of aminotransferases activity in the acute period of the radiation sickness being natural. Introduction of pyridoxal phosphate irradiated animals promotes relative normalization of activity of the enzymes under study.
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PMID:[Effect of pyridoxal phosphate on the activity of aminotransferases in different structure-functional regions of the rabbit brain in radiation sickness]. 816 Mar 1

Using 98 plasma samples from cancer patients undergoing antineoplastic chemotherapy, we compared the activities of aspartate aminotransferase and alanine aminotransferase measured by two different methods, with and without the addition of pyridoxal-5'-phosphate to the assay medium. Pyridoxal-5'-phosphate caused an increase of 1 to 20 U/l in aspartate aminotransferase and alanine aminotransferase activity in 90 and 78 patient plasma samples, respectively. Increases of aspartate aminotransferase and alanine aminotransferase activity of more than 20 U/l were observed in 8 and 20 samples, respectively. In 8 cases, the increase in alanine aminotransferase activity was greater than 50 U/l, whereas a similar increase in aspartate aminotransferase activity was decreased in only 2 cases. The considerable pyridoxal-5'-phosphate activation in aminotransferase activity observed in the plasma of a significant number of patients suggests that the use of the method with pyridoxal-5'-phosphate is advisable for a correct measurement of the catalytic concentration of aminotransferases in the plasma of patients undergoing chemotherapy.
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PMID:Importance of pyridoxal-5'-phosphate addition to the assay medium for the measurement of catalytic concentrations of plasma aspartate and alanine aminotransferases in patients undergoing antineoplastic chemotherapy. 883 Oct 54

With regard to adding Pyridoxal Phosphate (PALP), which combines with the active sites of AST and ALT, JSCC recommends measuring holoenzymes without adding PALP, reflecting the biological reaction. On the other hand, IFCC recommends the measurement of both holoenzymes and apoenzymes when PALP is added, reflecting the total diverted from the internal organs. It is important which recommendation to follow from a clinical point of view and from the viewpoint of reducing gaps in clinical facilities. Further, it is necessary to consider each isozyme as well as the time difference between apoenzyme and holoenzyme diversion from blood to accurately grasp the pathology and understand the measurement.
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PMID:[Aspartate aminotransferase (glutamic oxalacetic transaminase) and alanine aminotransferase (glutamic pyruvic transaminase)]. 1179 83