| Abstract: | In experiments on rabbits anesthetized with urethane, we made multichannel coherent recordings of spontaneous activity and evoked activity of preganglionic sympathetic fibers in peripheral nerves of a leg and unmyelinated preganglionic fibers of the cervical sympathetic nerve trunk (CSNT). The results of a spectral analysis of the activity recorded and a correlational analysis of the activity and changes in arterial pressure allow us to conclude that preganglionic unmyelinated fibers of the CSNT are primarily vasoconstrictive and are under stronger baroreceptor control than vasoconstrictive fibers going to the skin and limb muscles. This is possibly due to differences in the functions of the innvervated organs. The latent period of the change in arterial pressure evoked by a change in the activity of vasoconstrictor fibers equals 4–10 sec.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 23, No. 3, pp. 266–273, May–June, 1991. |
