Alterations in proton leak, oxidative status and uncoupling protein 3 content in skeletal muscle subsarcolemmal and intermyofibrillar mitochondria in old rats

Table 2 Oxidative capacities in homogenates, intermyofibrillar and subsarcolemmal skeletal muscle mitochondria from adult and old rats

	Adult	Old
Whole Tissue Homogenate
ngatoms oxygen/(min x g wet tissue)
state 3	4520 ± 220	3590 ± 185*
state 4	779 ± 48	630 ± 50*
RCR	5.8 ± 0.2	5.7 ± 0.2
Intermyofibrillar Mitochondria
ngatoms oxygen/(min x mg protein)
state 3	756 ± 48	577 ± 48*
state 4	131 ± 8	101 ± 10*
RCR	5.8 ± 0.1	5.7 ± 0.1
Subsarcolemmal Mitochondria
ngatoms oxygen/(min x mg protein)
state 3	434 ± 20#	370 ± 20#*
state 4	83 ± 4#	73 ± 6#*
RCR	5.2 ± 0.1	5.1 ± 0.1

Values are the means ± SEM of eight different rats. *P < 0.05 compared to adult rats; #P < 0.05 compared to intermyofibrillar mitochondria (non parametric two-way ANOVA). RCR = respiratory control ratio.

ISSN: 1471-2318