Differential effects of zidovudine and zidovudine triphosphate on mitochondrial permeability transition and oxidative phosphorylation.
Br J Pharmacol
; 121(7): 1295-300, 1997 Aug.
Article
em En
| MEDLINE
| ID: mdl-9257906
ABSTRACT
1. The effects of zidovudine (ZDV) and zidovudine triphosphate (ZDV-3P) on Ca2+-induced mitochondrial permeability transition (MPT), respiratory control ratio (RCR) and ATP synthesis have been investigated on isolated rat liver mitochondria. 2. ZDV slightly but significantly decreased RCR and ATP synthesis but was ineffective in inhibiting MPT. In contrast, ZDV-3P did not alter RCR and ATP synthesis but strongly inhibited MPT (IC50 = 3.0 +/- 0.9 microM). 3. The effect of ZDV-3P on mitochondrial swelling required a preincubation time. When incubated 10 min with mitochondria, ZDV-3P (8 microM) totally inhibited the rate of swelling. 4. ADP, ATP and atractyloside, which are agents known to interact with the mitochondrial adenine nucleotide carrier (ANC), antagonized the effect of ZDV-3P on mitochondrial swelling. Indeed, the IC50 value of ZDV-3P increased from 3.0 to 17.4, 93.6 and 66.5 microM, in the presence of 20 microM, ADP, ATP or atractyloside, respectively. 5. ZDV-3P did not displace [3H]-ATP from its mitochondrial binding site(s) whereas ADP and atractyloside did, suggesting that ZDV-3P and [3H]-ATP do not share the same binding sites. 6. ZDV-3P did not affect either mitochondrial respiration or ATP synthesis but inhibited Ca2+-dependent mitochondrial swelling. It was concluded that mitochondrial toxic effects observed during the chronic administration of ZDV cannot be related to its active metabolite (ZDV-3P).
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Antivirais
/
Fosforilação Oxidativa
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Nucleotídeos de Timina
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Mitocôndrias Hepáticas
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Zidovudina
Limite:
Animals
Idioma:
En
Revista:
Br J Pharmacol
Ano de publicação:
1997
Tipo de documento:
Article
País de afiliação:
França