Modulation of neonatal rat hypoglossal motoneuron excitability by serotonin
Neuroscience LettersPublished 1 August 1992
Albert J. Berger, Douglas A. Bayliss, Félix Viana
Citations175
SJR quartileQ2
SJR score0.77
SNIP0.67
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TL;DR
5-HT increases the excitability of neonatal HMs via at at least two different postsynaptic mechanisms via at leastTwo different post synapse mechanisms.
Abstract
The effects of 5-HT on neonatal rat hypoglossal motoneurons (HMs) were studied in two in vitro slice preparations. Serotonin caused either reversible depolarization or the generation of an inward current (I5-HT) in every cell tested. I5-HT persisted after synaptic blockade. In most of the cells tested, the magnitude of I5-HT was independent of membrane potential (-50 to -120 mV), and 5-HT had little effect on input resistance or slope conductance. In addition, 5-HT significantly reduced the amplitude of the post-spike medium-duration afterhyperpolarization. This reduction probably contributed to the resulting increase in the slope of the relationship describing the steady-state firing frequency response to injected current (f-I) observed in the presence of 5-HT. Thus, 5-HT increases the excitability of neonatal HMs via at least two different postsynaptic mechanisms.
Keywords
MedicineNeuroscienceBiochemistry, Genetics and Molecular Biology
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