Triggered oscillations in type A dorsal root ganglion neurons induced by veratridine.
- Author:
Jian-Hong DUAN
1
;
Yu-Bin DUAN
;
Jun-Ling XING
;
San-Jue HU
Author Information
1. Institute of Neurosciences, The Fourth Military Medical University, Xi an 710032, China. wgzsdjh@sohu.com
- Publication Type:Journal Article
- MeSH:
Action Potentials;
physiology;
Animals;
Female;
Ganglia, Spinal;
cytology;
drug effects;
Male;
Neurons, Afferent;
physiology;
Rats;
Rats, Sprague-Dawley;
Sodium Channel Blockers;
pharmacology;
Veratridine;
pharmacology
- From:
Acta Physiologica Sinica
2002;54(3):208-212
- CountryChina
- Language:Chinese
-
Abstract:
Veratridine, a blocker of inactive gate of sodium channel, was used to perfuse L5 dorsal root ganglion (DRG) topically. Afferent activities of type A single fiber from these DRGs were recorded. It was found that after a 10-min bath of veratridine (1.8-3 micromol/L), some of the primary silent DRG neurons were triggered by touch or pressure on the receptive fields or by electrical stimulation of the sciatic nerve to produce high-frequency firing, which was termed triggered oscillation presenting a U-type of interspike intervals (ISI) or other types of oscillations. The longer the intervals between stimulating pulses, the more stimulating pulses were needed to trigger the oscillation. The oscillation, triggered by electric stimuli with different duration or patterns, had no significant difference in their patterns. The duration of the inhibitory period after a triggered oscillation was generally 30-90 s. It was also observed that this kind of triggered oscillation was induced by afferent pulses of the same neurons. These results suggest that triggered oscillation, which may contribute to the fit of triggered pain, can be produced in primary sensory neurons after application of veratridine.
