Plasma lactate dehydrogenase and pyruvate kinase activity changes with body mass and age across birds and mammals

Abstract Birds and mammals produce most adenosine triphosphate (ATP) through mitochondrial oxidative phosphorylation, but when oxygen is not present in sufficient levels, ATP can be produced anaerobic glycolysis. Pyruvate kinase (PK) catalyzes the final step of glycolysis by converting phosphoenolpyruvate diphosphate (ADP) into pyruvate ATP. Lactate dehydrogenase (LDH) important for catalyzing conversion lactate. In this study, we measured LDH PK activities plasma from birds order to determine relationship between with respect body mass age. Our results show that had a higher activity compared mammals. There positive only. However, disappears data are phylogenetically corrected. We did observe significant age or Plasma was negatively correlated positively associated both The may complex due differences metabolism Increases linked demands flight, especially larger birds. A decrease age/MLSP (maximum lifespan) reflect differing metabolic shift as help them cope greater energetic needs cells