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Legends
Figure 1 Focal cerebral infarct areas (S1 to S6) among the experimental groups after 15 min of ischemia followed by 3 d of reperfusion (n = 4 to 6). 2,3,5-Triphenyltetrazolium chloride staining showed the infarct area as white and the noninfarct
area as red. Sham, sham group; Model, model group; EA, EA group; Non-acup, non-acup group; U0126+EA, U0126+EA group; Vehicle+EA, vehicle+EA group. Scale bar = 1 cm
Figure 2 Effects of EA at acupoints on cerebral infarct and neurological status. (A) The percentage of cerebral infarct areas among the sham, model, EA, non-acup, U0126+EA, and vehicle+EA groups were measured after 3 d of reperfusion. (B) The neurological deficit scores among the sham, model, EA, non-acup, U0126+EA, and vehicle+EA groups were measured after 1 d and 3 d of reperfusion. Data are presented as mean ± SD. *P < 0.05 compared with the sham group; #P < 0.05 compared with the model group
Figure 3 Effect of EA at acupoints on BDNF expression in the ischemic cortex. (A) Representative photograph showed a brain coronal section (TTC stain) from posterior bregma 0.92 mm. The dotted line square indicates the area of evaluation of immunopositive cells. C, the ischemic area of the cortex. Dotted line square = 1 mm2. (B) Representative photographs showed BDNF expression in the ischemic cortex of the sham, model, EA, non-acup, and U0126+EA groups after 3 d of reperfusion. N, negative control stain. Arrow indicates a BDNF-positive cell. Scale bar = 50 μm.
Figure 4 Effects of EA at acupoints on pRaf-1, pMEK1/2, and pERK1/2 expression.
(A) Representative photographs showed pRaf-1, (B) pMEK1/2, and (C) pERK1/2 expression in the ischemic cortex of the sham, model, EA, non-acup, and U0126+EA
groups after 3 d of reperfusion. N, negative control stain. Arrows indicate immunopositive cells. Scale bar = 50 μm.
Figure 5 Effects of EA at acupoints on pp90RSK, active caspase-3-NeuN, and TUNEL expression. (A) Representative photographs showed pp90RSK expression, (B) active caspase-3 (red) colocalizing with NeuN (blue), and (C) TUNEL-positive cells in the ischemic cortex of the sham, model, EA, non-acup, and U0126+EA groups after 3 d of reperfusion. N, negative control stain. Arrows in (A) and (C) indicate pp90RSK- and TUNEL-positive cells, respectively. Arrow in (B) indicates active caspase-3-NeuN double-labeled cells (purple), shown at higher magnification in the bottom right panel. Scale bar = 50 μm
Figure 6 Effects of EA at acupoints on cytosolic expression of pMEK1/2, pERK1/2, pp90RSK, and pBad. (A) Representative western blot images showed the cytosolic expression of pMEK1/2, pERK1/2, pp90RSK, and pBad in the ischemic cortex in the sham, model, EA, non-acup, and U0126+EA groups after 3 d of reperfusion. Actin was used as an internal control. The relative cytosolic expression of (B) pMEK1/2, (C) pERK1/2, (D) pp90RSK, and (E) pBad (n = 4) was assessed in the ischemic cortex in the sham, model, EA, non-acup, and U0126+EA groups. Data are presented as mean ± SD. #P
< 0.05 compared with the model group
Table 1 Expression of BDNF-, pRaf-1-, pMEK1/2-, pERK1/2-, pp90RSK-, and TUNEL-positive cells (counts/1 mm2)
Sham Model EA Non-acup U0126+EA
BDNF 0±0 186±46* 413±60*# 178±51* 393±63*#
pRaf-1 0±0 149±39* 348±55*# 187±67* 338±25*#
pMEK1/2 0±0 165±54* 274±31*# 149±52* 83±54*
pERK1/2 0±0 257±52* 417±36*# 219±57* 198±35*
pp90RSK 0±0 261±107* 497±31*# 302±98* 196±50*
TUNEL 0±0 365±88* 209±59*# 356±80* 339±79*
Mean± SD. (n = 5 or 6). Sham, sham group; Model, model group; EA, EA group; Non-acup, non-acup group; U0126+EA, U0126+EA group. *P < 0.05 vs. sham group; #P < 0.05 vs. model group