Analysis of metabolic control: new insights using scaled creatine kinase model
Abstract
The creatine kinase-adenylate kinase equilibria equations are given a dimensionless form by normalizing to total creatine concentration. Analysis with appropriate equilibrium and cation-binding constants identified two sharply separated phases of energy depletion. In the "buffering" phase, energy is derived from phosphocreatine. In the "depleting" phase, adenine nucleotides are the source of energy. Defining the state of the adenine nucleotide pool requires only pH, phosphocreatine, and creatine concentrations. Analysis of data from skeletal muscle, heart, brain, and smooth muscle demonstrated that the [free adenine nucleotide]/[total creatine] and [total phosphate]/[total creatine] are essentially constant over the greater than 20-fold concentration range among tissues and species. This result permits quantitative evaluation of cell energetics with data scaled to the total phosphate, as obtained with nuclear magnetic resonance studies, or to total creatine, as obtained in chemical analysis of freeze-trapped tissue. By applying the stability of the tissue parameters to the equations, it is demonstrated that unique identification of a hypothesis describing the recruitment of O2 uptake requires testing at several pH values.
Read the paper
Related studies
- Biportal endoscopic versus microscopic lumbar decompressive laminectomy in patients with spinal stenosis: A randomized controlled trial
- A whey protein-based multi-ingredient nutritional supplement stimulates gains in lean body mass and strength in healthy older men: A randomized controlled trial
- Supplement-based nutritional strategies to tackle frailty: A multifactorial, double-blind, randomized placebo-controlled trial
- A randomized, double-blind, placebo-controlled, proof-of-concept trial of creatine monohydrate as adjunctive treatment for bipolar depression
- Creatine supplementation (3 g/day) and bone health in older women: a 2-year, randomized, placebo-controlled trial
- A Multi-Ingredient Nutritional Supplement in Combination With Resistance Exercise and High-Intensity Interval Training Improves Cognitive Function and Increases N-3 Index in Healthy Older Men: A Randomized Controlled Trial
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.