Aging effects on oxidative phosphorylation in rat adrenocortical mitochondria.
Does aging in itself lead to alteration in adrenocortical mitochondrial oxidative phosphorylation? Mitochondria from Fischer 344 (F344) rats (6 and 24 months old), Brown Norway rats (6 and 32 months old) and F344-Brown Norway hybrid rats (6 and 30 months old) were compared. Mitochondria were isolated from extirpated adrenal cortex. The yields of mitochondria were quantitatively similar in all rat strains irrespective of age. In order to assess the activity of each mitochondrial complex, several different substrates were tested and the rate of oxidative phosphorylation measured. Aging does not affect mitochondrial activity except in the F344 rat adrenal cortex where the maximal ADP-stimulated oxidative phosphorylation decreased with age. We hypothesize that impaired synthesis of steroid hormones by the adrenal cortex with age in F344 rats might be due to decreased adrenocortical mitochondrial oxidative phosphorylation. We conclude that aging results in adrenocortical mitochondria effects that are non-uniform across different rat strains.
Departments of Pharmacology and of Medicine and Center for Mitochondrial Disease, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, United States.
Paola
P
Solinas
Electron Microscopy Facility and Center for Mitochondrial Disease, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, United States.
Hisashi
H
Fujioka
Department of Epidemiology and Biostatistics, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, United States.
Tomas
T
Radivoyevitch
Department of Biological Sciences, School of Dental Medicine, and Center for Mitochondrial Disease, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, United States.
Bernard
B
Tandler
Departments of Pharmacology and of Medicine and Center for Mitochondrial Disease, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, United States. Electronic address: charles.hoppel@case.edu.
Charles L
CL
Hoppel
D000302:Adrenal Cortex / Q000378:metabolism*; D000375:Aging / Q000378:metabolism*; D000818:Animals; D008928:Mitochondria / Q000378:metabolism*; D010085:Oxidative Phosphorylation; D051381:Rats; D011916:Rats, Inbred F344
Adrenal cortex; Aging; Fischer 344 rat; Mitochondria; Oxidative phosphorylation