[Effect of electroacupuncture on expressions of Lyn and Syk in mast cells of subcutaneous loose connective tissue in rats with urticarial].

OBJECTIVE: To observe the effect of electroacupuncture (EA) preconditioning on the expressions of tyrosine kinase Lyn and spleen tyrosine kinase (Syk) in mast cells of subcutaneous loose connective tissue in the rats with urticaria and explore the potential biological mechanism of EA in the intervention of urticaria. METHODS: A total of 32 SD rats were randomized into a blank group, a model group, an EA group and a positive medication group, 8 rats in each one. Except of the blank group, the passive cutaneous anaphylaxis (PCA) was adopted to prepare the model of urticaria in the rats of the rest three groups. In the EA group, EA was applied to bilateral "Quchi" (LI 11), "Xuehai" (SP 10) and "Zusanli" (ST 36), with disperse-dense wave, 2 Hz/15 Hz in frequency and 1 mA in current intensity, once daily, for 20 min each time, consecutively for 7 days. In the positive medication group, loratadine (1 mg•kg-1•d-1) was for intragastric administration, once daily, consecutively for 7 days. The samples were collected for index detection 30 min after PCA antigen challenge in the rats of each group. Spectrophotometer was adopted to determine the effusion quantity of Evans blue in the allergized site of skin. HE staining was used to observe the morphological changes in the allergized site of skin. Toluidine blue staining was provided to observe mast cell degranulation in subcutaneous loose connective tissue in the allergized site of skin. Immunohistochemistry was applied to determine the protein expressions of Lyn and Syk during degranulation of mast cells. RESULTS: In the rats of the odel group, the eipdermis of allergized site was thickening, cells were disorganized in hierarchy and inflammatory cells were infiltrated largely in the dermis. In the positive medication group and the EA group, the epidermis was getting thin, cell arrangement was clear and the inflammatory cell infiltration was obviously alleviated as compared with the model group. Compared with the blank group, the OD value of skin dye effusion quantity, the degranulation rate of mast cells and the positive expressions of Lyn and Syk were all increased in the model group (P<0.01). Compared with the model group, the OD value of skin dye effusion quantity, the degranulation rate of mast cells and the positive expressions of Lyn and Syk were all reduced in the EA group and the positive medication group (P<0.01). Compared with the positive medication group, the degranulation rate of mast cells was increased significantly in the EA group (P<0.01). CONCLUSION: Electroacupuncture at "Quchi" (LI 11), "Xuehai" (SP 10) and "Zusanli" (ST 36) reduces vascular permeability and gives play to the role of anti-allergy by the way of regulating and controlling the degranulation of mast cells in the rats with urticaria and the effect mechanism of electroacupuncture may be related to the inhibition of protein expressions of Lyn and Syk in mast cells.

[Electroacupuncture improves cutaneous allergic reaction by inhibiting degranulation of intrape-ritoneal mast cells, MAPK signaling and inflammatory factor levels in urticaria rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on degranulation of intraperitoneal mast cells (MCs) and expression of mitogen-activated protein kinase (MAPK) signaling related proteins, tumor necrosis factor-α(TNF-α) and interleukin-6 (IL-6) in urticaria rats, so as to reveal its mechanisms underlying improvement of urticaria. METHODS: Thirty-two SD rats were randomly divided into control，model，EA and medication groups (n＝8 in each group). The urticaria model was established by using passive cutaneous anaphylaxis (PCA) reaction method. EA (2 Hz /15 Hz, 1 mA) was applied to bilateral "Zusanli"(ST36), "Quchi "(LI11) and "Xuehai"(SP10) for 20 min，once daily for 7 consecutive days before antigen attack. Rats of the medication group were treated by gavage of Loratadine(1 mg•kg－1•d－1)for 7 days. The diameter of cutaneous Evan's blue spots was measured to evaluate the severity of PCA. Intraperitoneal fluid smears were prepared to observe the degranulation state of MCs. The contents of TNF-α and IL-6 in the intraperitoneal fluid were detected by ELISA, and the expression of extracellular signal-regulated kinase (ERK), phosphorylated (p)-ERK, c-Jun N-terminal kinase (JNK), p-JNK, P38MAPK and p-P38MAPK of the acquired intraperitoneal MCs was detected by Western blot. RESULTS: The diameter of cutaneous Evan's blue spot was significantly increased in the model group than that in the control group (P<0.01), and considerably decreased in both EA and medication groups compared with the model group(P<0.01). After modeling，the percentage of degranulated MCs, contents of TNF-α and IL-6, and expression levels of ERK, p-ERK, JNK, p-JNK, P38MAPK and p-P38MAPK were remarkably increased in the mo-del group than those in the control group (P<0.01, P<0.05). After the treatment, the percentage of degranulated MCs, contents of TNF-α and IL-6, and expression levels of p-ERK, JNK, p-JNK and p-P38MAPK were obviously decreased in both EA and medication groups relevant to the model group (P<0.01, P<0.05), while no significant changes were found in the expression of ERK in both EA and medication groups, and P38MAPK in the EA group. Compared with the model and EA groups, expression levels of P38MAPK were down-regulated in the medication group (P<0.05). CONCLUSION: EA can reduce skin allergic reaction in rats with urticaria, which may be related to its effects in inhibiting the degranulation of intraperitoneal MCs, down-regulating the expression of MAPK signaling-related proteins and the level of pro-inflammatory factors TNF-α and IL-6 in intraperitoneal MCs.

[Effect of deep and shallow electroacupuncture stimulation at "Huantiao"(GB30) on expression of phosphorylated-p38 and phosphorylated-p53 proteins and apoptosis in dorsal root ganglia in sciatic nerve injury rats].

OBJECTIVE: To observe the effect of deep electroacupuncture (EA) stimulation at "Huantiao"(GB30) on hindlimb motor function and expression of p38 mitogen-activated protein kinase (p38 MAPK ) and p53 proteins in dorsal root ganglia (DRG) in rats with chronic constrictive injury (CCI) of sciatic nerve. METHODS: Forty-eight SD rats (half male and half female) were randomly divided into control, model, shallow EA (SEA) stimulation and deep EA (DEA) stimulation groups (n=12 in each group). The CCI model was constructed by implanting a silicone tube close to the sciatic nerve of the left hind limb. For DEA group and SEA group, filiform acupuncture needles were inserted into GB30 about 12-14 mm deep and 5-8 mm deep (monitored by using a high-frequency ultrasound device), respectively, followed by electrical stimulation (2 Hz/100 Hz, 1 mA) using an EA stimulator. The intervention was conducted for 15 min every time, once daily for 14 days. The sciatic nerve function index (SFI) calculated to assess the motor function status. Histopathological changes of the sciatic nerve were displayed by H.E. staining. The expression levels of phosphorylated-p38 MAPK (p-p38) and phosphorylated-tumor protein p53 (p-p53) in DRGs of L4-L5 on the affected side were observed by immunohistochemical staining. RESULTS: Following modeling, the SFI were significantly decreased (P<0.01), and the expression levels of p-p38 and p-p53 proteins of L4-L5 DRGs were considerably increased in the model group (P<0.05). After the intervention, the SFI were obviously increased, and the expression levels of p-p38 and p-p53 proteins notably down-regulated in both DEA and SEA groups relevant to the model group (P<0.01, P<0.05). The therapeutic effect of DEA was significantly superior to that of SEA in raising SFI and down-regulating expression le-vels of p-p38 and p-p53 proteins (P<0.01, P<0.05). H.E. staining showed disordered arrangement of the sciatic nerve fibers and myelin, disaggregation of the myelin and axons with deformity and vacuolation in some of them and with an increase of Schwann cells in the model group, which was relatively milder in both DEA and SEA groups. CONCLUSION: Both DEA and SEA at GB30 can obviously improve the motor function in CCI rats, which may be associated with its function in down-regulating the expression of p-p38 and p-p53 proteins in L4-L5 DRGs, restraining p38 MAPK signaling. The therapeutic effect of DEA is evidently better than that of SEA.

[Lower frequency electroacupuncture is better in promoting recovery of limb locomotion in rats with sciatic nerve injury by reducing local inflammatory reaction].

OBJECTIVE: To observe the effect of different frequencies (2 Hz, 100 Hz) of electroacupuncture (EA) on limb locomotion and the expression of inflammatory factors IL-1ß, IL-6, TNF-α in sciatic nerve, and nuclear factor kappa B (NF-κB) in lumber(L)4-L5of spinal cord in rats with sciatic nerve injury (SNI), so as to reveal its mechanisms underlying improvement of SNI. METHODS: A total of 48 SD rats (half male and half female) were equally divided into blank control, model, low frequency (2 Hz) EA and high frequency (100 Hz) EA groups. The SNI model was established by clamping the spinal nerve. EA intervention (2 Hz, 100 Hz, 1 mA), starting on the 8th day after modeling, was applied to "Huantiao" (GB30) on the injured side for 15 min, once daily for 14 consecutive days. The sciatic function index (SFI) was calculated to assess the injured hindlimb recovery with reference to BAIN's and colleagues' methods. Histopathological changes of the sciatic nerve were displayed by H.E. staining. The expressions of IL-1ß, IL-6 and TNF-α in the sciatic nerve tissue were detected by immunohistochemistry, and the expression of NF-κB in the spinal cord was detected by using Western blot. RESULTS: After modeling, the SFI level on day 8 was significantly decreased in the model group (P<0.01), and no significant differences were found among the model, low frequency EA and high frequency EA groups before the EA intervention (P>0.05). Following the treatment (at the 22nd day), the SFI values of both low frequency EA and high frequency EA groups were significantly increased (P<0.01), suggesting an improvement of the limb motor function, and the SFI of the low frequency EA group was notably higher than that of the high frequency EA group (P<0.01). In comparison with the blank control group, the expression levels of IL-1ß, IL-6, TNF-α in the sciatic nerve and NF-κB protein in the spinal cord were significantly up-regulated (P<0.05). Following EA intervention, the increased expression levels of IL-1ß, IL-6, TNF-α and NF-κB proteins were significantly down-regulated in both low frequency EA and high frequency EA groups (P<0.05), and the therapeutic effect of low frequency EA was markedly superior to that of high frequency EA in down-regulating the expression levels of IL-1ß, IL-6, TNF-α and NF-κB protein (P<0.05). H.E. staining showed increase of Schwann cells in number, cellular swelling, and disintegration of the axons and myelin sheath, and appearance of vacuolar degeneration in the model group, which was relatively milder in both low frequency EA and high frequency EA groups, particularly in the low frequency EA group. CONCLUSION: EA of GB30 at 2 Hz and 100 Hz can promote the recovery of hindlimb motor function in SNI rats, which is probably related to its function in inhibiting the inflammatory response, and facilitating the repair of the damaged sciatic nerve. 2 Hz EA is better than 100 Hz EA in the therapeutic effect.