Estimation of conduction velocity in bulbospinal excitatory pathways to sympathetic outflows in cat spinal cord.
Experiments were performed on cats to measure the conduction velocity of the bulbospinal sympatho-excitatory axons. The lateral white matter of the cervical spinal cord and regions of the medulla were systematically explored for sympatho-excitatory points whilst recording from two sympathetic preganglionic outflows simultaneously. These were chosen a suitable distance apart to give a clear difference in latency to enable precise calculation of axonal conduction velocity between the two outflows. In addition, in a few cases conduction velocity was also measured by determining the latency shift of evoked responses, resulting from moving the stimulating electrode a known distance closer to the recording site. Conduction velocities of sympatho-excitatory axons in the spinal cord determined by these two procedures lay in the range 1.6-7.9 m/s.
D000818:Animals; D001370:Axonal Transport; D001369:Axons / Q000502:physiology; D002415:Cats; D004553:Electric Conductivity; D004558:Electric Stimulation; D008526:Medulla Oblongata / Q000033:anatomy & histology / Q000502:physiology*; D012154:Reticular Formation / Q000502:physiology; D013116:Spinal Cord / Q000502:physiology*; D013564:Sympathetic Nervous System / Q000502:physiology*