[Penetration of lipoproteins and apolipoproteins of very low density into the myocardium and changes of its structure in rat heart perfusion].
The method of electron microscopy, involving extra-low density lipoproteins (ELDLP) marked by colloid gold as well as their protein components (i.e. apolipoproteins--apoELDLP), was made use of to show that they are captured by capillary endotheliocytes of the isolated perfusing rat heart. Receptor-mediated endocytosis is the main mechanism of penetration. Within 30 minutes, ELDLP interact with the capillary wall, pass through the endothelial barrier and, from the intersticium, they are captured by tissue microphages, which induces their activity. They have, on the whole, a positive effect on the intactness of muscle cells of the beating heart. During the same time span, apoELDLP remain in endotheliocytes, however, they exert a pronounced negative impact on the myocardium. The capillary endothelium, in whose cells the lysosomal apparatus activates itself and clasmatosis sets on, is affected morphologically most of all. The impairment of the capillary endothelium, development of the perivascular edema and a reduced coronary flow trigger a sequence of events leading to enhanced cytolytic processes in the myocardium due to an activated lysosomal apparatus of cells.
L E
LE
Panin
V F
VF
Maksimov
I M
IM
Korostyshevskaia
A R
AR
Kolpakov
D000818:Animals; D001053:Apolipoproteins / Q000378:metabolism* / Q000648:ultrastructure*; D002465:Cell Movement / Q000502:physiology*; D066298:In Vitro Techniques; D008074:Lipoproteins / Q000378:metabolism* / Q000648:ultrastructure*; D008079:Lipoproteins, VLDL / Q000378:metabolism; D008297:Male; D009206:Myocardium / Q000378:metabolism* / Q000648:ultrastructure*; D051381:Rats; D017208:Rats, Wistar
D001053:Apolipoproteins; D008074:Lipoproteins; D008079:Lipoproteins, VLDL