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Effects of arsenic on pyruvate dehydrogenase activation.

Our studies illuminate a particular site of altered pyruvate utilization by liver mitochondria isolated from arsenic-fed rats. Initially, pyruvate dehydrogenase (PDH) levels were measured before and after in vitro activation. The liver homogenates were prepared from male rats given access to deioniz...

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Detalles Bibliográficos
Autores principales: Schiller, C M, Fowler, B A, Woods, J S
Formato: Texto
Lenguaje:English
Publicado: 1977
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1637432/
https://www.ncbi.nlm.nih.gov/pubmed/908299
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author Schiller, C M
Fowler, B A
Woods, J S
author_facet Schiller, C M
Fowler, B A
Woods, J S
author_sort Schiller, C M
collection PubMed
description Our studies illuminate a particular site of altered pyruvate utilization by liver mitochondria isolated from arsenic-fed rats. Initially, pyruvate dehydrogenase (PDH) levels were measured before and after in vitro activation. The liver homogenates were prepared from male rats given access to deionized drinking water solutions containing 0, 20, 40, and 85 ppm arsenic as sodium arsenate (As+5) for 3 and 6 weeks. After 3 weeks, the effects of arsenic at the highest dose level were pronounced on the basal activity (before activation), with inhibition up to 48% of the control values. The total PDH (after activation) was inhibited by 14, 15, and 28% of the control values at 20, 40, and 85 ppm As+5, respectively. A similar pattern of inhibition of PDH was observed at 6 weeks, although the inhibition was lower at the highest dose. This effect is probably a reflection of mitochondrial regeneration at this time and dose. The inhibition of PDH both before and after activation suggests a direct arsenic effect on pyruvate utilization which does not involve a lipoic acid moiety. Evidence is also presented which indicates an arsenic effect on the regulating kinase and/or phosphatase. The metabolic effects of impaired mitochondrial utilization by pyruvate are also discussed.
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spelling pubmed-16374322006-11-17 Effects of arsenic on pyruvate dehydrogenase activation. Schiller, C M Fowler, B A Woods, J S Environ Health Perspect Research Article Our studies illuminate a particular site of altered pyruvate utilization by liver mitochondria isolated from arsenic-fed rats. Initially, pyruvate dehydrogenase (PDH) levels were measured before and after in vitro activation. The liver homogenates were prepared from male rats given access to deionized drinking water solutions containing 0, 20, 40, and 85 ppm arsenic as sodium arsenate (As+5) for 3 and 6 weeks. After 3 weeks, the effects of arsenic at the highest dose level were pronounced on the basal activity (before activation), with inhibition up to 48% of the control values. The total PDH (after activation) was inhibited by 14, 15, and 28% of the control values at 20, 40, and 85 ppm As+5, respectively. A similar pattern of inhibition of PDH was observed at 6 weeks, although the inhibition was lower at the highest dose. This effect is probably a reflection of mitochondrial regeneration at this time and dose. The inhibition of PDH both before and after activation suggests a direct arsenic effect on pyruvate utilization which does not involve a lipoic acid moiety. Evidence is also presented which indicates an arsenic effect on the regulating kinase and/or phosphatase. The metabolic effects of impaired mitochondrial utilization by pyruvate are also discussed. 1977-08 /pmc/articles/PMC1637432/ /pubmed/908299 Text en
spellingShingle Research Article
Schiller, C M
Fowler, B A
Woods, J S
Effects of arsenic on pyruvate dehydrogenase activation.
title Effects of arsenic on pyruvate dehydrogenase activation.
title_full Effects of arsenic on pyruvate dehydrogenase activation.
title_fullStr Effects of arsenic on pyruvate dehydrogenase activation.
title_full_unstemmed Effects of arsenic on pyruvate dehydrogenase activation.
title_short Effects of arsenic on pyruvate dehydrogenase activation.
title_sort effects of arsenic on pyruvate dehydrogenase activation.
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1637432/
https://www.ncbi.nlm.nih.gov/pubmed/908299
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