Spinal Serotonergic and Opioid Receptors Are Involved in Electroacupuncture-Induced Antinociception at Different Frequencies on ZuSanLi (ST 36) Acupoint

Figure 5

Pretreatment with 5,7-DHT influences EAc-induced antinociception in different frequencies on the 1st (a, b, c) and 7th (d, e, f) days. (a), (d): 1 mA, 2 Hz EAc; (b), (e): 1 mA, 10 Hz EAc; (c), (f): 1 mA, 100 Hz EAc; ↓: initiation point of EAc except sham group. ○: sham group. ⚫: ACSF (artificial CSF). ▲: 5, 7-DHT (5,7-dihydroxy tryptamine, serotonin neurotoxin, 100 μg/10 μL, i.t.). Data are shown as mean ± S.E. ^∗𝑃<0.05, ^∗∗𝑃<0.01, and ^∗∗∗𝑃<0.001 compared to the ACSF group (𝑛=10).

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