Abstract: Affection of hyperhomocysteinemia on sympathetic nervous function of 2 type diabetic mellitus WANG suhong, ZHANG zhecheng, LIU na, ZHU ju, ZHANG jing Department of Neurology, The Third Central Clinical College of Tianjin Medical University, Tianjin 300170,China Abstrict Object:To investigate affection of hyperhomocysteinemia（Hhcy）on sympathetic nervous function of 2 type diabetic mellitus（DM）by detection of sympathetic skin reflex（SSR）.Methods:44 patients with 2 type DM were divided two groups: Hhcy group(n=22) and NHhcy group(n=22).Detection of SSR were given to four limbs of all patients, record and compare average latencies、amplitudes and ratios of upper to lower limbs. Results: SSR upper limbs latencies in Hhcy group [(1593.11±149.85)ms] were prolonged than that in NHhcy [(1539.75±149.22)ms](p>0.05).SSR lower limbs latencies in Hhcy group [(2795.86±415.24)ms] were prolonged than that in NHhcy group [(2617.93±327.61)ms](p＜0.05). SSR upper limbs amplitudes in Hhcy group [(1.03±0.38)mv] were reduced than that in NHhcy group [(1.22±0.30mv) (p＜0.01).SSR lower limbs amplitudes in Hhcy group [(0.28±0.17)mv]were reduced than that in NHhcy group [（0.38±0.15)mv](p＜0.01). Amplitude ratios of upper to lower limbs in Hhcy group were higher than that in NHhcy group, z=3.5176, p＜0.001;but latency ratios of upper to lower limbs between 2 groups had not statistical significance。Conclusion：Hhcy may increase the damage to sympathetic nervous of 2 type DM; it has features of Length dependence, and detection of SSR provides Simple and feasible technique.

Key words: homocysteinediabetes mellitus, type 2diabetic neuropathiessympathetic nervous systemextremitiessympathetic skin reflex