Pérez H, Hernández A, Ruiz S, Paeile C, Soto-Moyano R
Laboratorio de Neurofisiología y Biofísica, Universidad de Chile, Santiago.
Brain Res Bull. 1993;32(6):685-8. doi: 10.1016/0361-9230(93)90174-a.
The effects of neonatal capsaicin treatment (50 mg/kg, SC, at day 2 of postnatal life) on C-fiber excitability and dorsal horn C-input processing were studied through recording of a C-fiber-evoked spinal flexor reflex in 55-60-day-old rats, anesthetized with urethane (1.1 g/kg, IP) and spinalized at Th9-10. Neonatal capsaicin resulted in decreased C-fiber excitability, as revealed by increased chronaxie values determined in a strength-duration paradigm. Besides, capsaicin-treated rats exhibited a reduced potentiation of the C-reflex discharge in response to repetitive stimulation. The results indicate that capsaicin given to rats early in life leads to both functional disturbances of surviving C-fibers and altered temporal synaptic processing of the C-input in the spinal cord.
通过记录在55 - 60日龄大鼠中由C纤维诱发的脊髓屈肌反射，研究了新生期辣椒素处理（出生后第2天，50 mg/kg，皮下注射）对C纤维兴奋性和背角C纤维输入处理的影响。这些大鼠用乌拉坦（1.1 g/kg，腹腔注射）麻醉，并在胸9 - 10节段进行脊髓横断。新生期辣椒素导致C纤维兴奋性降低，这在强度 - 时间关系范式中测定的时值增加中得以体现。此外，辣椒素处理的大鼠对重复刺激的C反射放电增强作用减弱。结果表明，在生命早期给予大鼠辣椒素会导致存活C纤维的功能障碍以及脊髓中C纤维输入的时间性突触处理改变。
