Related Experiment Videos
Age differences in responsiveness of brainstem chemosensitive neurons to extracellular pH changes
J A Whittaker1, C O Trouth, Y Pan
1Department of Physiology and Biophysics, College of Medicine, Howard University, Washington, D.C. 20059.
Life Sciences
|January 1, 1990
Summary
Neurons in the brainstem (VMS) show varying sensitivity to pH changes with age. Adult cats exhibit the highest sensitivity, while newborns show the least, with sensitivity increasing with age.
Area of Science:
- Neuroscience
- Respiratory Physiology
Background:
- The ventrolateral surface of the medulla oblongata (VMS) is crucial for respiratory control.
- Chemosensitive neurons in the VMS respond to changes in extracellular fluid pH.
Purpose of the Study:
- To investigate the age-dependent sensitivity of VMS neurons to extracellular pH changes.
- To compare neuronal responses in newborn, young, and adult cats.
Main Methods:
- Superfusion of the VMS with artificial cerebrospinal fluid (CSF) at varying pH levels (7.0, 7.4, 7.8).
- Recording neuronal firing rates in response to pH alterations.
- Analysis of neuronal sensitivity across different age groups.
Main Results:
- A total of 97 neuronal units showed inverse firing rate changes with ECF pH.
- Adult cats displayed the highest neuronal sensitivity to acid superfusion.
- Newborn kittens (1-6 days) showed the least sensitivity, while young kittens (4-6 weeks) had intermediate sensitivity.
Conclusions:
- Neuronal sensitivity to pH changes in the VMS matures with age.
- Kittens older than 7 weeks exhibit adult-like response patterns.
- Developmental changes in VMS neuronal sensitivity are significant for respiratory regulation.