Abstract
Responses arising in ventral root filaments and antidromic discharges of single sympathetic preganglionic neurons in the lateral horn of gray matter in segment L2 of the cat spinal cord were recorded during stimulation of the white rami communicantes in the same segment. Conduction velocities, thresholds, and refractory periods were determined for individual groups of sympathetic preganglionic fibers. Excitation was conducted more slowly along the intramedullary part of the axons of some sympathetic neurons than along the extramedullary part. In a third group of neurons studied the second antidromic discharge appeared in response to paired stimulation if the interstimulus interval was appreciably longer than their refractory period. It is postulated that axons of sympathetic preganglionic neurons in the lumber spinal cord have a thin intramedullary part and are supplied with recurrent collaterals.
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Additional information
I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. Translated from Neirofiziologiya, Vol. 6, No. 2, pp. 143–151, March–April, 1974.
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Lebedev, V.P., Skobelev, V.A. & Bushmarina, T.A. Properties of axons of sympathetic preganglionic neurons in the cat lumbar spinal cord. Neurophysiology 6, 111–118 (1974). https://doi.org/10.1007/BF01062746
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DOI: https://doi.org/10.1007/BF01062746