Related Experiment Videos
High pressure modifies respiratory activity in isolated rat brain stem-spinal cord
1Department of Physiology, Corob Center for Medical Research, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
Journal of Applied Physiology (Bethesda, Md. : 1985)
|August 1, 1991
Summary
Hyperbaric pressure depresses central respiratory activity in isolated rat brain stems. However, it can make intact systems hyperexcitable to sensory input, altering respiratory control.
Area of Science:
- Neuroscience
- Physiology
- Hyperbaric Medicine
Background:
- Hyperbaric pressure exposure is known to cause motor and respiratory issues in humans and animals.
- Understanding the direct effects on the respiratory control center is crucial for managing these conditions.
Purpose of the Study:
- To investigate the impact of hyperbaric pressure on the respiratory center's rhythmic activity.
- To assess how pressure affects respiratory responses to sensory input from cranial nerves.
Main Methods:
- Utilized isolated brain stem-spinal cord preparations from newborn rats to eliminate peripheral sensory feedback.
- Measured the effects of hyperbaric pressure on central respiratory drive (inspiratory activity).
- Examined alterations in respiratory center responses to trigeminal and vagal nerve stimulation under pressure.
Main Results:
- Hyperbaric pressure significantly reduced the mean inspiratory drive in C5 ventral roots.
- Pressure diminished the inhibitory effects of trigeminal and vagal nerve stimulation on respiratory activity.
- In some instances, pressure reversed normal inhibition into excitation from sensory nerve stimulation.
Conclusions:
- Hyperbaric pressure depresses intrinsic central respiratory activity when sensory input is absent.
- In intact systems, pressure may disrupt the balance of excitation and inhibition, leading to hyperexcitability.
- This suggests a complex, potentially dual role of hyperbaric pressure on respiratory control mechanisms.