Phrenic nerve inputs to upper cervical (C1–C3) spinothalamic tract neurons in monkeys

摘要: Afferent input from the phrenic nerve enters mid-cervical spinal segments, and previous results in monkeys show that spinothalamic (STT) neurons are activated by groups II III afferent arising diaphragm. In rats, dorsal horn C1-C2 segments receive stimulated above heart, but not diaphragm or abdomen. It is known if this differential organization occurs primate STT neurons. We hypothesized high cervical also would be preferentially inputs thoracic structures, such as pericardium. examined extracellular discharge rate of C1-C3 for responses to electrical stimulation fibers. Responses ipsilateral fibers heart were compared effects below contralateral input. concluded upper most strongly excited small diameter group IV diaphragmatic well have a lesser effect on thus might involved nociceptive processing.