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Title: The potassium channel subunit K v β1 serves as a major control point for synaptic facilitation
Analysis of the presynaptic action potential’s (AP syn ) role in synaptic facilitation in hippocampal pyramidal neurons has been difficult due to size limitations of axons. We overcame these size barriers by combining high-resolution optical recordings of membrane potential, exocytosis, and Ca 2+ in cultured hippocampal neurons. These recordings revealed a critical and selective role for K v 1 channel inactivation in synaptic facilitation of excitatory hippocampal neurons. Presynaptic K v 1 channel inactivation was mediated by the K v β1 subunit and had a surprisingly rapid onset that was readily apparent even in brief physiological stimulation paradigms including paired-pulse stimulation. Genetic depletion of K v β1 blocked all broadening of the AP syn during high-frequency stimulation and eliminated synaptic facilitation without altering the initial probability of vesicle release. Thus, using all quantitative optical measurements of presynaptic physiology, we reveal a critical role for presynaptic K v channels in synaptic facilitation at presynaptic terminals of the hippocampus upstream of the exocytic machinery.  more » « less
Award ID(s):
1750199
NSF-PAR ID:
10233030
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
117
Issue:
47
ISSN:
0027-8424
Page Range / eLocation ID:
29937 to 29947
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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