ISSN:
1432-2307
Keywords:
Myocardial ultrastructure
;
Mitochondrial swelling
;
Stereology
;
Correlations of structural parameters
;
Cardiac arrest and global ischaemia
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary Cellular changes occuring in the left ventricular myocardium during ischaemia after different methods of cardiac arrest have been evaluated by morphological and morphometric parameters: volume densities of mitochondria (VVMi), sarcoplasm (VVSp), myofibrils (VVMf), surface densities of mitochondria (SVMi). The surface to volume ratio of mitochondria (SVratioMi) has been used as an independent parameter of mitochondrial swelling. Since ischaemic swelling of myocardial cells increases the volume of the reference space and ischaemic swelling of mitochondria decreases the free sarcoplasm, VVMi and VVSp cannot be considered as reliable indicators of the degree of oedema. SVMi/VVMf remains nearly constant after different forms of cardiac arrest, demonstrating the integrity of mitochondrial outer membranes. The inverse linear ratio between SVratioMi and the mean mitochondrial volume indicates that the increase in mitochondrial volume is achieved by surface smoothing. Loss of matrix structure and fragmentation of cristae occur at an SVratioMi of about 5.8, cristolysis at 5.5 to 5.6 and amorphous matrix densities at an SVratioMi of less than 5.5 μm2/μm3. The SVratioMi is a suitable parameter for evaluating mitochondrial swelling both at the onset and during global myocardial ischaemia, independent of the method of cardiac arrest used. It serves as an indicator of the state of structural preservation of mitochondria during ischaemia.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01605291
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