Naturally occurring polyamines (spermidine, putrescine, cadaverine), as the well studied spermine, are transported into rat liver mitochondrial matrix provided that mitochondria are energized and the electrical membrane potential has a value of about 180 mV. This condition is achieved by the presence of inorganic phosphate, or acetate, or nigericin in the incubation medium. Valinomycin plus K+ almost completely blocks polyamine transport. The obtained results clearly show that all naturally occurring polyamines are transported by an electrophoretic mechanism in responce to a high negative inner electrical potential. The distribution ratio of polyamines across the mitochondrial membrane is far from the thermodynamic equilibrium by many orders of magnitude. This result might suggest the existence of a different pathway for polyamine efflux.

Electrophoretic polyamine transport in rat liver mitochondria

TONINELLO, ANTONIO;DALLA VIA, LISA;
1992

Abstract

Naturally occurring polyamines (spermidine, putrescine, cadaverine), as the well studied spermine, are transported into rat liver mitochondrial matrix provided that mitochondria are energized and the electrical membrane potential has a value of about 180 mV. This condition is achieved by the presence of inorganic phosphate, or acetate, or nigericin in the incubation medium. Valinomycin plus K+ almost completely blocks polyamine transport. The obtained results clearly show that all naturally occurring polyamines are transported by an electrophoretic mechanism in responce to a high negative inner electrical potential. The distribution ratio of polyamines across the mitochondrial membrane is far from the thermodynamic equilibrium by many orders of magnitude. This result might suggest the existence of a different pathway for polyamine efflux.
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11577/2485395
Citazioni
  • ???jsp.display-item.citation.pmc??? 1
  • Scopus 6
  • ???jsp.display-item.citation.isi??? ND
social impact