Comparative erythrocyte metabolism in marsupials and monotremes

Abstract

Concentrations of ATP and DPG, activities of 10 enzymes and the glycolytic rates were measured in the erythrocytes of 11 species of marsupials and two species of monotremes. Mean DPG concentrations were greater in the erythrocytes of marsupials than those of eutherian mammals. The opposite is true of ATP. Significant findings from the results of enzyme activities were: high activity of hexokinase (7.39 ± 0.82 EU/g Hb) in the short-beaked echidna, pyruvate kinase (37.49 ± 1.0 EU/g) Hb in bridled nailtail wallaby and glucose-6-phosphate dehydrogenase (G6PD; 41.66 ± 1.24 EU/g Hb) in black-striped wallaby. About 6-to 7-fold difference in the activity of G6PD levels between the two species of wombats was confirmed. Glucose phosphate isomerase activity was also shown to be twice as high in the red cells of the common wombat compared with those of the southern hairy nosed wombat. There were wide variations in the glycolytic rate among the species examined.

Correlação of enzimas eritrocitárias e seus compostos intermediários de mamíferos selecionados

“…5,10,16,17 A remarkable variation among the studied mammalian species has been observed, consistent with other authors' findings. 6,9,10,11,12,18 The present study demonstrated that most of the enzymes do not show any correlation with ATP and 2,3-BPG, but triose phosphate isomerase and 2,3-bisphosphoglycerate mutase showed significant coefficients of correlation of Pearson (r : 0.5, p<0.001) for ATP concentrations, as well as 2,3-bisphosphoglycerate mutase activity with the intracellular 2,3-BPG concentrations (r : 0.6, p<0.001). These findings suggest that most of glycolytic enzymes activities in normal individuals do not affect the rate and yield in terms of ATP and 2,3-BPG except triose phosphate isomerase and 2,3-bisphosphoglycerate mutase.…”

“…The glycolytic pathway also exhibits the attached Luebering-Rappaport shunt, in which the 2,3-bisphosphoglycerate (2,3-BPG) is formed, the metabolite which regulates the hemoglobin affinity to the molecular oxygen. 1,2,3,4 The Embden Meyerhoff pathway enzymes and the intermediary compounds (ATP and 2,3-DPG) in the erythrocytes have been studied in several species of animals 5,6,7,8,9,10,11,12 as well as some other enzymes which protect the red blood cells against oxidative damage. 5,10,11,12 However, no reference was found about the correlation of the enzyme activities and the concentration of ATP and 2,3-BPG among mammalian species.…”

Assessment of the hemorheological profile of koala and echidna

“…Marsupials and monotremes have been the subject of limited hematological (Parsons et al, 1971), immunological (Jurd, 1994) and energy metabolism studies (Parkinson et al, 1995). Parsons and co-workers report that several hematological parameters of echidnas are within the normal mammalian range, although hemoglobin properties differed from those for placental mammals (Parsons et al, 1971).…”

Estudo complementar da glicose-6-fosfato desidrogenase eritrocitária do marsupial brasileiro Didelphis marsupialis

“…Entre estas citadas características, juntou-se o achado da hiperatividade da glicose-6-fosfato desidrogenase (G6PD) eritrocitária por Barretto et al (21) . Assim, sua atividade é cerca de 15-20 vezes a observada nos humanos, 6 vezes nos ratos Wistar, 4 vezes no cangurú australiano (22) . .…”