Hydrogen ion buffering during complete brain ischemia

Hydrogen ion balance during exercise

This paper discusses certain aspects of the metabolic acidosis which accompanies heavy exercise, concentrating on the factors influencing hydrogen ion production and the associated effects on carbon dioxide output and ventilation. Classical concepts of lactic acidosis in exercise were established many years ago (Hill, 1932; Margaria, Edwards & Dill, 1933) and continue to be widely accepted. In ...

Brain phospholipid metabolism during ischemia.

Brain Phospholipid Metabolism During Ischemia • Molecular mechanisms accounting for the vulnerability of brain to ischemic damage are incompletely understood. To assess the role of membrane integrity, phospholipid metabolism is investigated in subcellular organelles of brain following varying degrees of ischemia. Global brain ischemia is produced in rabbits by combining hypotension and hypoxia ...

Hydrogen ions kill brain at concentrations reached in ischemia.

Elevation of brain glucose before the onset of nearly complete ischemia leads to increased lactic acid within brain. When excessive, such acidosis may be a necessary factor for converting selective neuronal loss to brain infarction from nearly complete ischemia. To examine the potential neurotoxicity of excessive lactic acid concentrations, we microinjected (0.5 microliter/min) 150 mM sodium la...

Interaction of intracellular ion buffering with transmembrane-coupled ion transport

The role of the Na/Ca exchanger in the control of cellular excitability and tension development is a subject of current interest in cardiac physiology. It has been suggested that this coupled transporter is responsible for rapid changes in intracellular calcium activity during single beats, generation of plateau currents, which control action potential duration, and control of intracellular sod...

The Brain During Bypass: Ischemia, Emboli, Insult