کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
3122005 1583405 2006 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effect of electrical stimulation of the internal capsule on nociceptive neurons responding to orofacial stimuli in the medullary dorsal horn of the rat
موضوعات مرتبط
علوم پزشکی و سلامت پزشکی و دندانپزشکی دندانپزشکی، جراحی دهان و پزشکی
پیش نمایش صفحه اول مقاله
Effect of electrical stimulation of the internal capsule on nociceptive neurons responding to orofacial stimuli in the medullary dorsal horn of the rat
چکیده انگلیسی

SummaryInternal capsule (IC) stimulation has been used clinically to alleviate central pain. However, the neuronal mechanisms underlying pain relief by IC stimulation are poorly understood. In order to elucidate the analgesic mechanism, the effect of IC conditioning stimulation on nociceptive neurons in the rat medullary dorsal horn was investigated in the present study. Rats were anaesthetized with N2O–O2 (2:1) and 0.5% halothane and were immobilized with pancuronium bromide. Two kinds of nociceptive neurons, wide dynamic range (WDR) and nociceptive specific (NS) neurons, responding to noxious stimulations of the face and oral structures were recorded in the trigeminal caudal nucleus and the medial reticular subnuclei. A test stimulus with a single rectangular pulse (2 ms in duration, 5–70 V) was applied to the centre of the receptive field. Responses in 55.9% of the WDR neurons and in 60% of the NS neurons were inhibited by conditioning stimuli to the ipsilateral IC with trains of 33 pulses (100–300 μA) at 330 Hz. The percents of peak inhibitory effects on WDR neurons and NS neurons were 78.1 ± 25.0% (n = 19) and 89.0 ± 13.6% (n = 3), respectively. The inhibitory effect continued for conditioning-test intervals of up to 500 ms. Effective sites for conditioning stimulation were concentrated in the lateral side of the IC. These findings suggest that modulation of nociceptive transmission by IC stimulation occurs at second-order neurons via a presynaptic phenomenon by corticofugal fibers in the IC.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Archives of Oral Biology - Volume 51, Issue 10, October 2006, Pages 930–939
نویسندگان
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