对胃的功能活动产生兴奋作用Objective: To observe the distribution of substance P like immunoreactivity(SP LI) in the nucleus of solitary tract(NTS)and the effect of electroacupuncture(EA) at "Zusanli" (ST 36) on SP. Methods: Thirty SD rats were randomly and evenly divided into control group
"Zusnali" group and Non acupoint (about 0.5 cm beside "Zusali") group. EA (sparse dense waves
frequency of 16~ 20 Hz and strength that is able to induce slight muscular tremor) was applied to bilateral "Zusanli" (ST 36) for 20 min.Avidin biotin peroxidase complex (ABC) method of immunohistochemistry was employed to display SP LI of the bulb tissue sections. Results: Under light microscope
SP immuno reaction products mainly were cirsoid fibers
presenting dot like or strings of bead like
distributing mainly in the medial and commissural subnucleus of NTS (mNTS
cNTS) and the spinal nucleus of trigiminal nerve; while no immunoreactive neurons were seen in NTS. After EA stimulation of "Zusanli " (ST 36)
the light density of SP LI in the mNTS and cNTS increased significantly in comparison with control group and non acupoint group (P<0.05~0.01). No significant changes were seen in other nuclei as dorsal motor nucleus of the vagus
area postrema
etc. There was also no obvious difference between non acupoint group and control group in SP LI changes in every subnucleus of NTS. It showed that EA of "Zusanli"(ST 36) could inhibit release of SP. Conclusion: NTS is an important primary centre responsible for the regulative action of EA of "Zusanli" (ST 36) on the physiological activities of the stomach.