Author | dc.contributor.author | Ferreira, J. | |
Author | dc.contributor.author | Gil, Lionel | |
Admission date | dc.date.accessioned | 2019-01-29T12:39:49Z | |
Available date | dc.date.available | 2019-01-29T12:39:49Z | |
Publication date | dc.date.issued | 1987 | |
Cita de ítem | dc.identifier.citation | Biochemistry International, Volumen 15, Issue 1, 1987, Pages 95-109 | |
Identifier | dc.identifier.issn | 01585231 | |
Identifier | dc.identifier.uri | https://repositorio.uchile.cl/handle/2250/159650 | |
Abstract | dc.description.abstract | The uptake of Ca2+ by energized liver mitochondria was compared in normal fed as well as in protein-energy malnourished rats. In the presence of phosphate, mitochondria obtained from both groups were able to accumulate Ca2+ from the suspending medium and eject H+ during oxidation of common substrates which activate different segments of the respiratory chain. The rate of Ca2+ uptake was significantly lower in mitochondria from protein-energy malnourished rats. The rates of oxygen consumption and H+ ejection were decreased by 20-30% during oxidation of substrates at the three coupling sites. Similarly, mitochondria from protein-energy malnourished rats exhibit a 34% decrease in the maximal rate of Ca2+ uptake and a 25% lower capacity for Ca2+ load. The stoichiometric relationship of Ca2+/2e- remained unaffected. In steady state, with succinate as a substrate in the presence of rotenone and N-ethylmaleimide, mitochondria from normal fed and protein-energy malnourished rats showed a similar rate of Ca2+ uptake. Furthermore in both groups the stoichiometry of the H+/O ratio was close to 8.0 (H+/site ratio close to 4.0), and of Ca2+/site was close to 2.0. The diminished rate of Ca2+ uptake observed in mitochondria from protein-energy malnourished rats could be explained on the basis of a depressed rate of electron transport in the respiratory chain rather than by an effect at the level of the Ca2+ or H+ transport mechanism per se. | |
Lenguage | dc.language.iso | en | |
Source | dc.source | Biochemistry International | |
Keywords | dc.subject | Biochemistry | |
Título | dc.title | Nutritional effects on mitochondrial bioenergetics. Alterations in calcium uptake by rat liver mitochondria. | |
Document type | dc.type | Artículo de revista | |
dcterms.accessRights | dcterms.accessRights | Acceso a solo metadatos | |
Cataloguer | uchile.catalogador | jmm | |
Indexation | uchile.index | Artículo de publicación SCOPUS | |
uchile.cosecha | uchile.cosecha | SI | |