HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 92/1/648    most recent 01029.2003v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (7) Citing Articles via Google Scholar Google Scholar Articles by Nakayama, K. Articles by Kudo, N. Search for Related Content PubMed PubMed Citation Articles by Nakayama, K. Articles by Kudo, N.

REPORT

Rhythmic Motor Activity in Thin Transverse Slice Preparations of the Fetal Rat Spinal Cord

Department of Physiology, Institute of Basic Medical Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan

Submitted 24 October 2003; accepted in final form 10 March 2004

Networks generating locomotor-like rhythmic motor activity are formed during the last week of the fetal period in the rat spinal cord. We investigated the coordinated rhythmic motor activity induced in transverse slice preparations of the lumbar spinal cord taken from fetal rats as early as embryonic day (E) 16.5. In slices as thin as 100 µm, bath-application of 5-hydroxytryptamine (5-HT) induced rhythmic [Ca²⁺]_i elevations in motoneurons labeled with Calcium Green-1 dextran. The rhythmic [Ca²⁺]_i elevations were similar in frequency to that in the intact lumbar spinal cord, although there was no temporal correlation between the activity in the left and right sides of 100-µm slices. Such rhythmic [Ca²⁺]_i elevations were observed in the slices taken from all lumbar segments. Moreover, the rhythmic activity was abolished by simultaneous blockade of glutamate, glycine, and GABA_A receptors, indicating that synaptic transmission mediated by these receptors is important for the generation of the rhythm in these slices. Synchronous rhythmic activity between the left-right sides was found in slices thicker than 200 µm taken from any segmental level of the lumbar spinal cord. In these preparations, commissural neurons were activated synchronously with ipsilateral motoneurons. These results indicate that the neuronal networks sufficient to generate coordinated rhythmic activity are contained in one-half of a single lumbar segment at E16.5. Such spinal cord slices are a promising experimental model to investigate the neuronal mechanisms and the development of rhythm generation in the spinal cord.

This article has been cited by other articles:

				K. P. Carlin, Y. Dai, and L. M. Jordan Cholinergic and Serotonergic Excitation of Ascending Commissural Neurons in the Thoraco-Lumbar Spinal Cord of the Neonatal Mouse J Neurophysiol, February 1, 2006; 95(2): 1278 - 1284. [Abstract] [Full Text] [PDF]