Red Blood Cell Life Research Articles

Blood and Spleen Response to Isolation and Cold Stress in Little Brown Bats, Myotis lucifugus

AbstractFemale bats were housed singly or in groups and maintained at 5° or 23 °C. Red blood cell life spans were determined utilizing the disappearance of labeled sodium chromate (Cr51). Red cell counts, hematocrits, reticulocyte percentages and diameters, white cell differentials, and spleen histology were determined for bats subjected to three weeks of stress treatment. Isolated animals (warm and cold) had significantly lower hematocrits and red cell counts and significantly higher reticulocyte diameters and percentages than grouped bats. Random destruction of erythrocytes was initially higher in isolated bats. In cold and isolated animals the white pulp of the spleen was most reduced in quantity and in proliferative activity. Red pulp became highly engorged with erythrocytes and showed a hypertrophy of reticuloendothelial elements. Higher rates of random destruction are closely correlated with increased splenic erythrophagocytosis. Gold or isolation imposed separately are mild stress factors in little brown bats, while a severe stress response occurs when the two stressors are imposed simultaneously.

The life span of red blood cells in the amphibian larvae, Rana catesbeiana

Nearly one hundred amphibian tadpoles were made anemic by phenylhydrazine injection. During the recovery period radioactive thymidine was incorporated into the DNA of the nucleated amphibian red blood cells. Over the next 135 days blood was drawn and smears of circulating red blood cells were prepared. The blood smears from each tadpole were autoradiographed and percentage of labeled nuclei (PLN) determined. The average life span of tadpole red blood cells was calculated from the change in PLN, and is about 100 days. It is concluded that during the transition from tadpole to frog, the tadpole red blood cell life span must be drastically shortened to account for the hemoglobin transition observed during amphibian metamorphosis.

The use of 51Cr for sheep red blood cell survival studies.

The red blood cell half-life as determined by 51Cr-labelled autologous cells in five adult sheep was 13.7 days. In contrast, the red blood cell life span measured by cohort 59Fe-labelling in six adult sheep was 111.7 days. The rapid loss of 51Cr-activity from the circulation appears to result from rapid elution of the label from the circulating red cells. 51Cr does not appear to be a suitable isotope for erythrokinetic studies in sheep.

Effect of Environmental Temperature on the Life Span of Red Blood Cells in Domestic Fowl

The mean red blood cell life span was determined to two groups of 18 week old Athens Randombred male birds using a 51 Cr labeling procedure. There were eight birds in each group. One group was raised at 8°C. and the other at 30°C. There were no statistical differences due to temperature between the two groups which had mean red blood cell life spans of 27.4 and 26.7 days at 8° and 30°C., respectively.

Studies of bilirubin kinetics in normal adults

This report describes studies of bilirubin kinetics in 13 healthy young adults. The plasma content of unconjugated bilirubin-(14)C was determined at frequent intervals for 24-30 hr after the intravenous injection of a tracer dose of unconjugated isotopic bilirubin. Fecal and urinary radioactivity were measured for 7 days. During this time cumulative recovery averaged 96% of the injected dose. The plasma curves were processed by digital computer. For the 30 hr experimental period, a sum of three exponentials, with average half-times of 18, 81, and 578 min, was required to describe the data. Using the plasma curve integral method, the hepatic bilirubin clearance (47 +/-10 ml/min, mean +/-SD), the bilirubin production rate (3.8 +/-0.6 mg/kg per day), and the mean red blood cell life span (101 +/-13 days) were calculated directly from the parameters of this function. To gain further insight into the metabolism of unconjugated bilirubin, the data were also used to determine the parameters of a multicompartmental model. In the model proposed, plasma unconjugated bilirubin exchanges with two additional pools one of which is thought to represent extrahepatic extravascular, and the other intrahepatic unconjugated bilirubin. Bilirubin is eliminated from the system via the proposed intrahepatic pool. From the data and the model, pool sizes and exchange rates between compartments were calculated, and the liver: plasma concentration gradient estimated. These studies provide a detailed analysis of the kinetics of unconjugated bilirubin in a healthy normal population and are intended to serve as a reference point for studies of abnormal states.

Diagnosing hemolytic anemias in the laboratory.

Several laboratory procedures provide primary evidence of hemolytic disease. Since, by definition, hemolytic disease is an average red blood cell life span less than normal, a fundamental approach is to tag red cells with chromium51 and to measure their half-life in the circulation. A sustained reticulocytosis also indicates hemolytic disease.

59Fe study of red blood cells life span in glucose-6-phosphate dehydrogenase deficiency heterozygote.

In a presumptive heterozygote for congenital nonspherocytic hemolytic anemia caused by glucose-6-phosphate dehydrogenase deficiency, a fraction of short-living red blood cells was demonstrated by administration of nitrofurantoin in the 22nd day of the 59Fe study of erythrocyte life span. A small percentage of deficient red blood cells in peripheral blood in this case (4%) may originate in the shorter life span of deficient cells and in the proportion of the deficient to normal red blood cells produced.