Excitatory and inhibitory medullary nuclei projecting to spinal cardioacceleratory neurons in the cat

To identify medullary nuclei projecting to spinal sympathetic neurons cardioacceleratory sites in the right intermediolateral nucleus (ILN) in spinal segment T2 were electrically stimulated and the right medulla was explored for evoked antidromic activity. In 20 chloralosed, vagotomized cats evoked responses were observed at 264 histologically identified sites. The responses had a mean latency of 1.5 msec, followed the stimulus at 300 Hz and …