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Updated: Feb 22, 2026

In Vivo Calcium Imaging of Neuronal Ensembles in Networks of Primary Sensory Neurons in Intact Trigeminal Ganglia
Published on: August 1, 2025
Preganglionic stimulation increases calcium uptake by sympathetic ganglia
Abstract:
Isolated superior cervical ganglia of rats accumulate more calcium during preganglionic stimulation than do unstimulated controls; uptake of calcium-45 is approximately doubled by stimulation of 12 impulses per second. The extra uptake is markedly reduced by a high concentration of magnesium, but not by mecamylamine hydrochloride or tetraethylammonium chloride, although all three agents eliminate the postsynaptic action potential. Uptake of calcium-45 is also greatly increased by a high external concentration of potassium.
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