Wang J, Wang C Y, Guan X M
Department of Neurobiology, Tongji Medical University, Wuhan.
Sheng Li Xue Bao. 1997 Dec;49(6):618-24.
Dorsal cutaneous branches of the spinal nerves of T5-L1 segments on one side in anaesthesised rats were exposed and cut centrally. One peripheral end of the cut nerves was selected for antidromical stimulation, while an adjacent one for recording, both by Ag-AgCl electrodes. When a train of 50 Hz, 0.2 ms width square waves of 2 s was delivered to the nerve preparation for stimulation, the discharge of the adjacent nerve showed a remarkable increase and then subsided to the original level for about 25 s. Such experiments (n = 414) showed that the induced discharge frequency reached its maximum 2 s after the stimulation and maintained for another 2 s before subsiding to original level in about a period of 25 s. Using the discharge frequency at a certain time segment as an index, the degree of induced discharges of the recorded nerves were linearly related to their spontaneous discharges before stimulation and the sequences of stimulation to some extent. Single square stimulation was unable to induce one-to-one correspondent discharge in the recording nerve. Control experiments were done to rule out the induced discharges being due to the spreading of stimulating current. To summarize the results of all the above experiments, it appeared that some information transmission between sensory nerve endings may be present through some chemical events.
