Compensatory plasticity vs. synaptic scaling; not always one in the same
- UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
- Tanya Zubov (Creator)
- Institution
- The University of North Carolina at Greensboro (UNCG )
- Web Site: http://library.uncg.edu/
- Advisor
- Joseph Santin
Abstract: Neurons control their output over long time scales to generate behavior. One well-studied mechanism thought to achieve network homeostasis, synaptic scaling, involves a uniform increase in excitatory synaptic strength to oppose reduced network activity. Although synaptic scaling is hypothesized to retain the normal balance of synaptic weights, quantitative scaling across synapses does not always occur, leaving to question the purpose of scaling on network function. We addressed this issue in the respiratory network of frogs, as synaptic compensation regulates respiratory motor function after inactivity associated with aquatic hibernation. Here we confirm that inactivity during hibernation elicits synaptic compensation in motoneurons, with mean increases comparable to shorter-term pharmacological inactivity. Despite similar amounts of compensation, pharmacological inactivity failed to scale synapses, but hibernators showed evidence of scaling that persisted even when motor activity has recovered. Blocking L-type Ca2+ channels after hibernation disrupted quantitative scaling of synaptic strength but did not impair compensation, uncoupling the scaling organization from compensation. Scaling per se played a vital role in regulating the network because respiratory motor outflow was weaker when neurons failed to scale upregulated synaptic weights. Thus, hibernation triggers synaptic scaling, and once activity restarts, an activity dependent Ca2+ signal maintains the scaling organization to regulate motor output. These results reveal that the organization of synaptic weights can play a distinct role from compensation in network homeostasis and show that compensation alone is not sufficient to prevent maladaptive network outputs following activity perturbations. [This abstract has been edited to remove characters that will not display in this system. Please see the PDF for the full abstract.]
Compensatory plasticity vs. synaptic scaling; not always one in the same
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Created on 5/1/2021
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Additional Information
- Publication
- Thesis
- Language: English
- Date: 2021
- Keywords
- Compensation, Compensatory plasticity, Homeostasis, Neuron, Synaptic Scaling
- Subjects
- Adaptation (Physiology)
- Neurons $x Physiology
- Homeostasis
- Synapses