Changes in extracellular pH during electrical stimulation of isolated rat vagus nerve.
Double-barrelled pH-sensitive micro-electrodes were used to record changes of extracellular pH during repetitive stimulation of isolated rat vagus nerves. It was found that a small initial alkaline shift was followed by a prolonged acidification. The acidification was correlated in time with the poststimulus undershoot of the extracellular K+ activity and with the recovery phase of the nerve conduction velocity. In the presence of ouabain, the acid component of the pH change was completely abolished (indicating a metabolic origin), whereas the alkaline component remained unaltered. These pH changes were too small to make a significant contribution to the activity-related changes in conduction velocity of the vagal C-fibres.
W
W
Endres
P
P
Grafe
H
H
Bostock
G
G
ten Bruggencate
D000818:Animals; D002118:Calcium / Q000502:physiology; D004558:Electric Stimulation; D005071:Evoked Potentials; D005110:Extracellular Space / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D007473:Ion Channels / Q000378:metabolism; D009412:Nerve Fibers / Q000502:physiology; D009431:Neural Conduction; D051381:Rats; D012964:Sodium / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D014630:Vagus Nerve / Q000502:physiology*
D007473:Ion Channels; D012964:Sodium; D000254:Sodium-Potassium-Exchanging ATPase; D002118:Calcium