The 2- to 6-Hz oscillation in sympathetic nerve discharge is generated in the brain stem, as cervical spinal cord transection abolished SND while medullary oscillations remained unchanged.
The 2- to 6-Hz oscillation in sympathetic nerve discharge is generated in the brain stem, as evidenced by persistent medullary oscillations following spinal cord transection in animal models.
We tested the hypothesis that brain stem circuits normally generate a 2- to 6-Hz oscillation in sympathetic nerve discharge (SND). Experiments were performed on baroreceptor-denervated decerebrate cats and urethan-anesthetized rats in which renal or splanchnic SND was recorded along with field potentials (population activity) from sites in the rostral ventrolateral medulla, medullary raphe, or medullary lateral tegmental field. Our major findings were as follows. 1) Population activity recorded from the three medullary regions contained a 2- to 6-Hz oscillation. 2) The 2- to 6-Hz oscillation in population activity recorded from some medullary sites was correlated to that in SND. Peak coherence in the 2- to 6-Hz band approached a value of 1 in some cases. 3) Whereas cervical spinal cord transection abolished or markedly reduced SND, the 2- to 6-Hz oscillation in medullary activity was essentially unchanged. These results support the view that the 2- to 6-Hz oscillation in SND can be generated in the brain stem of cats and rats.
Zhong et al. (Mon,) reported a other. Cervical spinal cord transection vs. Intact spinal cord (baseline) was evaluated on Correlation between 2- to 6-Hz oscillation in medullary population activity and sympathetic nerve discharge. The 2- to 6-Hz oscillation in sympathetic nerve discharge is generated in the brain stem, as cervical spinal cord transection abolished SND while medullary oscillations remained unchanged.