Ok. Baskurt et al., EFFECT OF ERYTHROCYTE DEFORMABILITY ON MYOCARDIAL HEMATOCRIT GRADIENT, American journal of physiology. Heart and circulatory physiology, 37(1), 1995, pp. 260-264
Myocardial hematocrit gradient was determined between epicardium and e
ndocardium of the left ventricular wall in rat heart under the influen
ce of erythrocyte deformability alterations. Hematocrit determinations
were performed by measuring two different radionuclides labeling plas
ma (I-125-labeled albumin) and erythrocytes (Tc-99m) in 100-mu m-thick
left ventricular myocardium slices. Myocardial hematocrit gradient ca
lculated after exchange transfusions with partially hardened red blood
cell suspensions was compared with the results of the control group,
in which the exchange transfusions were done using normal, hematocrit-
matched blood. In the control group, the hematocrit value in the myoca
rdium adjacent to epicardium was 0.331 +/- 0.076 l/l and decreased to
0.232 +/- 0.054 l/l near the endocardium. Myocardial hematocrit betwee
n these two was represented by a linear gradient. In the group with im
paired erythrocyte deformability, the hematocrit value was 0.359 +/- 0
.074 l/l in the epicardial myocardium and remained at 0.341 +/- 0.082
l/l in the endocardial layer. These results indicate that tissue hemat
ocrit gradient in the left ventricular myocardium may be disturbed if
erythrocyte deformability is altered.