[Penetration of lipoproteins through a capillary wall and their effects on the cardiomyocyte ultrastructure during in vitro heart perfusion].
The colloidal gold-labeled lipoprotein (LP) distribution in the myocardium after the 30 min perfusion of isolated working rat heart was studied by electron microscopy. LP of physiological concentrations are shown to be able to interact with the capillary wall and they can be incorporated by endotheliocytes. The velocity and transportation mechanisms of different classes of LP differ. Very low density LP are the most intensively taken up, low density LP enter into interstitium more rapidly than others, high density LP do not leave the capillary wall at all. The passages of labeled LP through endotheliocytes by the receptor-mediated as well as the non-receptor manners are revealed. The transportation through the widened intercellular junctions may be supposed for low density LP. For the fist time LP addendum into the perfusion medium was shown to provoke the activation of interstitial macrophages. During the perfusion duration they take inside and accumulate labeled very low density LP and low density LP in their lysosomes. The internalization may be performed by the specific endocytosis or by the simple phagocytosis. The qualitative and morphometrical analyses show that LP preserve the capillary and cardiomyocyte ultrastructure from perfusion injuries. One may suppose that there are interrelations between the capillary endothelium, the interstitial macrophages and the parenchymal cells in myocardium for realization of plasma LP effects.
Maksimov
V F
VF
Institute of Biochemistry, Siberian Branch of RAMS, Novosibirsk.
Kolpakov
A R
AR
Korostyshevskaia
I M
IM
Panin
L E
LE
Shalbueva
N I
NI
D000818:Animals; D001692:Biological Transport; D002199:Capillary Permeability; D003326:Coronary Circulation; D017979:Gold Colloid; D066298:In Vitro Techniques; D008074:Lipoproteins / Q000493:pharmacokinetics*; D008854:Microscopy, Electron; D015425:Myocardial Reperfusion; D009206:Myocardium / Q000378:metabolism* / Q000648:ultrastructure*; D051381:Rats; D017208:Rats, Wistar
D017979:Gold Colloid; D008074:Lipoproteins