ISSN:
0021-9541
Keywords:
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
Liver mitochondria from normal and alloxan diabetic rats, isolated in 0.25 M sucrose, were assayed with an oxygen electrode for ADP/O and Ca+2/O ratios, respiratory ratio, and respiratory control index. Mitochondria were incubated with two substrates, succinate and β-hydroxybutyrate; two types of ionic media, Na+ medium (Na+ the major monovalent cation) and K+ medium (K+ the major monovalent cation); and two respiratory stimulants, ADP (352 μM) and Ca+2 (187 μM). Significant differences between respiratory rates and ADP/O ratios were dependent upon the substrate and ionic medium employed. The results confirm previous studies which showed no alteration in ADP/O ratio but decreased State 3 respiratory rates under similar conditions of K+ medium with ADP stimulation in the diabetic. Furthermore, the State 3 respiration was prolonged compared to normal. Ca+2 stimulation was the same in normal and diabetic mitochondria in K+ medium. Studies in Na+ media revealed more significant differences in RCI's, respiratory rates, and ADP/O ratios that were substrate dependent as well as ion dependent. The results from these various studies can be accounted for by an hypothesis linking mitochondrial K+ interaction with alterations in the diabetic mitochondria.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jcp.1040840212
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