ABSTRACT
Objective To investigate the effect of different function of sympathetic nerve on the pain of peripheral nerve chronic compression. Methods Forty-eight male Sprague-Dawley rats were made into lower trunk chronic compression models and divided into 6 groups (A1,B1,C1,A2,B2,C2) with 8 rats per group. The C8T1 dorsal root ganglions of the compressed sides of group A1 (control group), B1 (sympathetic block group)and C1 (de-sympathetic group) were harvested 3 months after compression surgery. The compressed lower trunks of group A2 (control group), B2(sympathetic block group)and C2(de-sympathetic group)were decompressed 3 months after compression surgery and bred for another month and then the C8T1 dorsal root ganglions of the compressed sides were harvested. The levels of substance P mRNA in the C8T1 dorsal root ganglions were tested with RT-PCR technique. Results the mean relative levels of substance P mRNA of group A1, B1 and C1 were (3.620 ± 0.830) × 10-2, (2.945 ± 0.724) × 10-2, (2.239 ± 0.734) × 10-2, respectively, with a significant difference (P = 0.006) and those of group A2, B2 and C2 were (3.163 ± 1.026) × 10-2, (2.355 ± 0.680) × 10-2,(1.487 ± 0.802) × 10-2, the difference among which was statistically significant (P = 0.003). Conclusion The pain of peripheral nerve chronic compression is affected by sympathetic function. The more lower the sympathetic function is, the more light the pain is. Sympathetic blockage or resection helps to relieve the pain of peripheral nerve compression disease after being decompressed.
ABSTRACT
Objective To explore sympathetic skin response (SSR) in the region innervated only by the median or ulnar nerve. Methods Thirty healthy volunteers, ten patients with median nerve injury, ten patients with ulnar nerve injury and three patients with both median and ulnar nerve injury were involved in the study. SSR was elicited by electrical stimulation and the latency and amplitude of the SSR were recorded in the center of the palm and on the hypothenar, and the pulps of the index and little fingers. Results After median nerve injury the SSR of the index finger pulp disappeared, the SSR amplitude of the palmar center was reduced, while the SSR amplitude of the little finger pulp was normal. In contrast, after ulnar nerve injury the SSR of the little finger pulp disappeared,the SSR amplitude of the hypothenar was reduced, while the SSR of the index finger pulp was normal. When both nerves were injured, no SSR could be elicited anywhere on the palm. Conclusions The SSR of the palmar center and hypothenar are affected by both the median and ulnar nerves. The index and little finger pulps are sites for recording SSR which represent the SSR of the median and ulnar nerve distribution, respectively. Index and little finger pulps are ideal sites for detec t ing efferent functioning of sympathetic nerves from the median and ulnar nerve paths,respectively.