Emergence of lung-inflation-related sympathetic nerve activity in spinal cord transected neonatal swine.

Sympathetic (SYMP) nerve activity in spinal intact neonatal swine is comprised of prominent bursts reflecting modulation by supraspinal structures involved in shaping central respiratory and baroreceptor activity. After spinal cord transection (SCT), we found no evidence of such modulation. SYMP activity was now related to the ventilatory cycle, exhibiting bursts only during lung inflation. Such activity suggests the emergence of latent spinal circuits which may have the capacity to regulate cardiovascular activity.