Characteristics of Myocardial Blood Vessels in Preterm Rats in the Late Postnatal Ontogeny.

Immunohistochemical study (CD31 detection) and morphometric analysis (evaluation of specific volumes of cardiomyocytes and blood capillaries, diameter of blood capillaries, trophic index, and pericapillary diffusion zone) of the left ventricular myocardium in preterm (12 h and 24 h preterm) Wistar rats was carried out on postnatal days 56 and 180. A decrease in the trophic index and an increase in the zone of pericapillary diffusion in the myocardium of the left ventricle in preterm rats were shown, which indicates deterioration of the heart supply during the postnatal ontogeny.