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Published on: February 10, 2014
Modulation of periodic cold receptor activity by ouabain
1Institut für Zoophysiologie, Universität Hohenheim, Stuttgart, Federal Republic of Germany.
Pflugers Archiv : European Journal of Physiology
|September 1, 1990
Summary
Ouabain affects feline cold receptors by altering their discharge patterns, suggesting the sodium-potassium (Na/K) pump contributes to signal transduction. This pump
Area of Science:
- Neuroscience
- Physiology
- Sensory Biology
Background:
- Cold receptors exhibit periodic discharge patterns crucial for thermoreception.
- The role of the sodium-potassium (Na/K) pump in sensory transduction is not fully understood.
Purpose of the Study:
- To investigate the contribution of Na/K pump activity to signal transduction in feline cold receptors.
- To analyze the effects of ouabain, a Na/K pump inhibitor, on cold receptor discharge patterns.
Main Methods:
- Recording afferent activity from cold fibers in an isolated feline tongue preparation.
- Characterizing periodic discharge patterns by oscillation frequency and impulse count per cycle.
- Administering ouabain (10(-7)-10(-6)M) to observe changes in receptor activity.
Main Results:
- Ouabain induced excitatory responses followed by inhibition in all tested cold receptors.
- Observed stereotyped modifications in oscillation frequency and impulse count per cycle.
- Peak oscillation frequency increased with higher static temperatures and exceeded control values.
Conclusions:
- The electrogenic Na/K pump plays a role in the transducer process of cold receptors.
- Inhibition of the Na/K pump leads to a depolarizing imbalance, accelerating oscillation frequency.
- Cold receptor oscillation frequency is modulated by temperature and membrane potential.
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