Low micromolar concentrations of 4-aminopyridine facilitate fictive locomotion expressed by the rat spinal cord in vitro
Section snippets
Experimental procedures
In accordance with NIH guidelines and the Italian act DL 27/1/92 n. 116 (implementing the European Community directives n. 86/609 and 93/88), experiments were performed on lumbar spinal cord preparations isolated from neonatal Wistar rats (0–5 days old) under urethane anesthesia (0.2 ml i.p. of a 10% w/v solution). All efforts were made to reduce the number of animals used and to minimize animal suffering. The experimental setup was the same as described by Marchetti et al. (2003), while full
Results
The database of the present study comprises 17 intracellularly recorded motoneurons with −77±5 mV resting potential and 37±13 MΩ input resistance. VR responses were collected from 71 spinal cord preparations.
Discussion
The principal finding of the present study is that low μM doses of 4-AP together with appropriate paradigms of concurrent CPG stimulation could activate and facilitate the function the locomotor CPG in the rat spinal cord. This result indicates that the mechanisms responsible for the action by 4-AP on spinal injury patients should include a central action of 4-AP, in addition to its well documented effect on conduction of nerve fibers (reviewed by Nashmi and Fehlings, 2001). In the absence of
Acknowledgements
This work was supported by a FIRB grant from MIUR.
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