Electroacupuncture may alleviate diabetic neuropathic pain by inhibiting the microglia P2X4R and neuroinflammation

Diabetic neuropathic pain (DNP) is a common and destructive complication of diabetes mellitus. The discovery of effective therapeutic methods for DNP is vitally imperative because of the lack of effective treatments. Although 2 Hz electroacupuncture (EA) was a successful approach for relieving DNP, the mechanism underlying the effect of EA on DNP is still poorly understood. Here, we established a rat model of DNP that was induced by streptozotocin (STZ) injection. P2X4R was upregulated in the spinal cord after STZ-injection. The upregulation of P2X4R was mainly expressed on activated microglia. Intrathecal injection of a P2X4R antagonist or microglia inhibitor attenuated STZ-induced nociceptive thermal hyperalgesia and reduced the overexpression of brain-derived neurotrophic factor (BDNF), interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in the spinal cord. We also assessed the effects of EA treatment on the pain hypersensitivities of DNP rats, and further investigated the possible mechanism underlying the analgesic effect of EA. EA relieved the hyperalgesia of DNP. In terms of mechanism, EA reduced the upregulation of P2X4R on activated microglia and decreased BDNF, IL-1β and TNF-α in the spinal cord. Mechanistic research of EA's analgesic impact would be beneficial in ensuring its prospective therapeutic effect on DNP as well as in extending EA's applicability.

Analgesic effect of electroacupuncture on bone cancer pain in rat model: the role of peripheral P2X3 receptor

Upregulation of P2X3 receptor (P2X3R) has been strongly implicated in nociceptive signaling including bone cancer pain (BCP). The present study, using rat bone cancer model, aimed to explore the role of P2X3R in regulating rat pain behavior under the intervention of electroacupuncture (EA). The BCP model was successfully established by injection with MRMT-1 breast cancer cell into the medullary cavity of left tibia for 3 × 10⁴ cells/3 μL PBS in rats as revealed by obvious bone destruction, decreased paw withdrawal thresholds (PWTs), and reduced paw withdrawal latencies (PWLs). Western blot analyses showed that P2X3R expression was significantly upregulated in ipsilateral lumbar 4-6 (L4-6) dorsal root ganglia (DRG), but the difference not seen in spinal cord dorsal horn (SCDH). With the in-depth study of P2X3R activation, we observed that intrathecal injection of P2X3R agonist α,β-meATP aggravated MRMT-1 induced BCP, while injection of P2X3R inhibitor A-317491 alleviated pain. Subsequently, we demonstrated that BCP induced mechanical allodynia and thermal hyperalgesia were attenuated after EA treatment. Under EA treatment, total P2X3R protein expression in ipsilateral DRGs was decreased, and it is worth mentioning that decreased expression of P2X3R membrane protein, which indicated that both the expression and membrane trafficking of P2X3R were inhibited by EA. The immunofluorescence assay showed that EA stimulation exerted functions by reducing the expression of P2X3R-positive cells in ipsilateral DRGs of BCP rats. Ca²⁺ imaging analysis revealed that the EA stimulation decreased the percentage of α,β-meATP responsive neurons in DRGs and inhibited calcium influx. Notably, the inhibitory effect of EA on mechanical allodynia and nociceptive flinches was abolished by intrathecal injection of α,β-meATP. These findings demonstrated EA stimulation ameliorated mechanical allodynia and thermal hyperalgesia in rat model of MRMT-1-induced BCP. EA exerts analgesic effect on BCP by reducing the overexpression and functional activity of P2X3R in ipsilateral DRGs of BCP rats. Our work first demonstrates the critical and overall role of P2X3R in EA's analgesia against peripheral sensitization of MRMT-1-induced BCP and further supports EA as a potential therapeutic option for cancer pain in clinic.

Inhibition of phosphorylated calcium/calmodulin-dependent protein kinase IIα relieves streptozotocin-induced diabetic neuropathic pain through regulation of P2X3 receptor in dorsal root ganglia

Diabetic neuropathic pain (DNP) is frequent among patients with diabetes. We previously showed that P2X3 upregulation in dorsal root ganglia (DRG) plays a role in streptozotocin (STZ)-induced DNP but the underlying mechanism is unclear. Here, a rat model of DNP was established by a single injection of STZ (65 mg/kg). Fasting blood glucose was significantly elevated from the 1^st to 3^rd week. Paw withdrawal thresholds (PWTs) and paw withdrawal latencies (PWLs) in diabetic rats significantly reduced from the 2^nd to 3^rd week. Western blot analysis revealed that elevated p-CaMKIIα levels in the DRG of DNP rats were accompanied by pain-associated behaviors while CaMKIIα levels were unchanged. Immunofluorescence revealed significant increase in the proportion of p-CaMKIIα immune positive DRG neurons (stained with NeuN) in the 2^nd and 3^rd week and p-CaMKIIα was co-expressed with P2X3 in DNP rats. KN93, a CaMKII antagonist, significantly reduce mechanical hyperalgesia and thermal hyperalgesia and these effects varied dose-dependently, and suppressed p-CaMKIIα and P2X3 upregulation in the DRGs of DNP rats. These results revealed that the p-CaMKIIα upregulation in DRG is involved in DNP, which possibly mediated P2X3 upregulation, indicating CaMKIIα may be an effective pharmacological target for DNP management.

Dorsal root ganglia P2X4 and P2X7 receptors contribute to diabetes-induced hyperalgesia and the downregulation of electroacupuncture on P2X4 and P2X7

Diabetic neuropathic pain (DNP) is highly common in diabetes patients. P2X receptors play critical roles in pain sensitization. We previously showed that elevated P2X3 expression in dorsal root ganglion (DRG) contributes to DNP. However, the role of other P2X receptors in DNP is unclear. Here, we established the DNP model using a single high-dose streptozotocin (STZ) injection and investigated the expression of P2X genes in the DRG. Our data revealed elevated P2X2, P2X4, and P2X7 mRNA levels in DRG of DNP rats. The protein levels of P2X4 and P2X7 in DNP rats increased, but the P2X2 did not change significantly. To study the role of P2X4 and P2X7 in diabetes-induced hyperalgesia, we treated the DNP rats with TNP-ATP (2',3'-O-(2,4,6-trinitrophenyl)-adenosine 5'-triphosphate), a nonspecific P2X1-7 antagonist, and found that TNP-ATP alleviated thermal hyperalgesia in DNP rats. 2 Hz electroacupuncture is analgesic against DNP and could downregulate P2X4 and P2X7 expression in DRG. Our findings indicate that P2X4 and P2X7 in L4-L6 DRGs contribute to diabetes-induced hyperalgesia, and that EA reduces thermal hyperalgesia and the expression of P2X4 and P2X7.

HLA class II immunogenic mutation burden predicts response to immune checkpoint blockade

BACKGROUND

Whereas human leukocyte antigen (HLA) class I mutation-associated neoantigen burden has been linked with response to immune checkpoint blockade (ICB), the role of HLA class II-restricted neoantigens in clinical responses to ICB is less studied. We used computational approaches to assess HLA class II immunogenic mutation (IMM) burden in patients with melanoma and lung cancer treated with ICB.

PATIENTS AND METHODS

We analyzed whole-exome sequence data from four cohorts of ICB-treated patients with melanoma (n = 110) and non-small-cell lung cancer (NSCLC) (n = 123). MHCnuggets, a neural network-based model, was applied to estimate HLA class II IMM burdens and cellular fractions of IMMs were calculated to assess mutation clonality. We evaluated the combined impact of HLA class II germline genetic variation and class II IMM burden on clinical outcomes. Correlations between HLA class II IMM burden and density of tumor-infiltrating lymphocytes were computed from expression data.

RESULTS

Responding tumors harbored a significantly higher HLA class II IMM burden for both melanoma and NSCLC (P ≤ 9.6e-3). HLA class II IMM burden was correlated with longer survival, particularly in the NSCLC cohort and in the context of low intratumoral IMM heterogeneity (P < 0.001). HLA class I and II IMM landscapes were largely distinct suggesting a complementary role for class II IMMs in tumor rejection. A higher HLA class II IMM burden was associated with CD4+ T-cell infiltration and programmed death-ligand 1 expression. Transcriptomic analyses revealed an inflamed tumor microenvironment for tumors harboring a high HLA class II IMM burden.

CONCLUSIONS

HLA class II IMM burden identified patients with NSCLC and melanoma that attained longer survival after ICB treatment. Our findings suggest that HLA class II IMMs may impact responses to ICB in a manner that is distinct and complementary to HLA class I-mediated responses.

Electroacupuncture Inhibits NLRP3 Activation by Regulating CMPK2 After Spinal Cord Injury

Objectives

This study aimed to evaluate the expression of cytosine monophosphate kinase 2 (CMPK2) and activation of the NLRP3 inflammasome in rats with spinal cord injury (SCI) and to characterize the effects of electroacupuncture on CMPK2-associated regulation of the NLRP3 inflammasome.

Methods

An SCI model was established in Sprague–Dawley (SD) rats. The expression levels of NLRP3 and CMPK2 were measured at different time points following induction of SCI. The rats were randomly divided into a sham group (Sham), a model group (Model), an electroacupuncture group (EA), an adeno-associated virus (AAV) CMPK2 group, and an AAV NC group. Electroacupuncture was performed at jiaji points on both sides of T9 and T11 for 20 min each day for 3 consecutive days. In the AAV CMPK2 and AAV NC groups, the viruses were injected into the T9 spinal cord via a microneedle using a microscope and a stereotactic syringe. The Basso–Beattie–Bresnahan (BBB) score was used to evaluate the motor function of rats in each group. Histopathological changes in spinal cord tissue were detected using H&E staining, and the expression levels of NLRP3, CMPK2, ASC, caspase-1, IL-18, and IL-1β were quantified using Western blotting (WB), immunofluorescence (IF), and RT-PCR.

Results

The expression levels of NLRP3 and CMPK2 in the spinal cords of the model group were significantly increased at day 1 compared with those in the sham group (p < 0.05). The expression levels of NLRP3 and CMPK2 decreased gradually over time and remained low at 14 days post-SCI. We successfully constructed AAV CMPK2 and showed that CMPK2 was significantly knocked down following 2 dilutions. Finally, treatment with EA or AAV CMPK2 resulted in significantly increased BBB scores compared to those in the model group and the AAV NC group (p < 0.05). The histomorphology of the spinal cord in the EA and AAV CMPK2 groups was significantly different than that in the model and AAV NC groups. WB, IF, and PCR analyses showed that the expression levels of CMPK2, NLRP3, ASC, caspase-1, IL-18, and IL-1β were significantly lower in the EA and AAV CMPK2 groups compared with those in the model and AAV NC groups (p < 0.05).

Conclusion

Our study showed that CMPK2 regulated NLRP3 expression in rats with SCI. Activation of NLRP3 is a critical mechanism of inflammasome activation and the inflammatory response following SCI. Electroacupuncture downregulated the expression of CMPK2 and inhibited activation of NLRP3, which could improve motor function in rats with SCI.

Amygdalar κ-opioid receptor-dependent upregulating glutamate transporter 1 mediates depressive-like behaviors of opioid abstinence

Opiates produce a strong rewarding effect, but abstinence from opiate use emerges with severe negative emotions. Depression is one of the most frequent emotion disorders associated with opiate abstinence, which is thought to be a main cause for relapse. However, neurobiological bases of such an aversive emotion processing are poorly understood. Here, we find that morphine abstinence activates κ-opioid receptors (KORs) by increasing endogenous KOR ligand dynorphin expression in the amygdala, which in turn facilitates glutamate transporter 1 (GLT1) expression by activation of p38 mitogen-activated protein kinase (MAPK). Upregulation of GLT1 expression contributes to opiate-abstinence-elicited depressive-like behaviors through modulating amygdalar glutamatergic inputs to the nucleus accumbens (NAc). Intra-amygdala injection of GLT1 inhibitor DHK or knockdown of GLT1 expression in the amygdala significantly suppresses morphine-abstinence-induced depressive-like behaviors. Pharmacological and pharmacogenetic activation of amygdala-NAc projections prevents morphine-abstinence-induced behaviors. Overall, our study provides key molecular and circuit insights into the mechanisms of depression associated with opiate abstinence.

Anxiolytic effect of GABAergic neurons in the anterior cingulate cortex in a rat model of chronic inflammatory pain

Chronic pain easily leads to concomitant mood disorders, and the excitability of anterior cingulate cortex (ACC) pyramidal neurons (PNs) is involved in chronic pain-related anxiety. However, the mechanism by which PNs regulate pain-related anxiety is still unknown. The GABAergic system plays an important role in modulating neuronal activity. In this paper, we aimed to study how the GABAergic system participates in regulating the excitability of ACC PNs, consequently affecting chronic inflammatory pain-related anxiety. A rat model of CFA-induced chronic inflammatory pain displayed anxiety-like behaviors, increased the excitability of ACC PNs, and reduced inhibitory presynaptic transmission; however, the number of GAD65/67 was not altered. Interestingly, intra-ACC injection of the GABA_AR agonist muscimol relieved anxiety-like behaviors but had no effect on chronic inflammatory pain. Intra-ACC injection of the GABA_AR antagonist picrotoxin induced anxiety-like behaviors but had no effect on pain in normal rats. Notably, chemogenetic activation of GABAergic neurons in the ACC alleviated chronic inflammatory pain and pain-induced anxiety-like behaviors, enhanced inhibitory presynaptic transmission, and reduced the excitability of ACC PNs. Chemogenetic inhibition of GABAergic neurons in the ACC led to pain-induced anxiety-like behaviors, reduced inhibitory presynaptic transmission, and enhanced the excitability of ACC PNs but had no effect on pain in normal rats. We demonstrate that the GABAergic system mediates a reduction in inhibitory presynaptic transmission in the ACC, which leads to enhanced excitability of pyramidal neurons in the ACC and is associated with chronic inflammatory pain-related anxiety.

[Comparison of the effect between electroacupuncture and NSAIDs on pain memory based on cAMP/PKA/CREB pathway in anterior cingulate gyrus]

OBJECTIVE

To observe the direct intervention effects of electroacupuncture (EA) and non-steroid anti-inflammatory drugs (NSAIDs) on pain memory, and to explore their effects on cAMP/PKA/cAMP pathway in anterior cingulate gyrus (ACC).

METHODS

Fifty clean healthy male SD rats were randomly divided into a control group, a model group, an indomethacin group, an EA group and a sham EA group, 10 rats in each group. Except the control group, the pain memory model was established in the remaining four groups by twice injection of carrageenan at foot; 0.1 mL of 2%λ-carrageenan was subcutaneously injected at the left foot of rats; 14 days later, when the pain threshold of rats of each group returned to the basic level, the second injection was performed with the same procedure. The rats in the EA group were treated with EA at bilateral "Zusanli" (ST 36) for 30 min; the rats in the indomethacin group was treated with indomethacin intragastric administration with the dose of 3 mg/kg; the rats in the sham EA group was treated with EA without electricity at the point 0.3 mm forward "Zusanli" (ST 36) with the depth of 2 mm for 30 min; the rats in the control group was not given any invention. All the above interventions were performed 5 h, 1 d, 2 d and 3 d after the second injection of 2% λ-carrageenan. The left-side paw withdrawal thresholds (PWT) were observed before the first injection, 4 h, 3 d, 5 d after the first injection, before the second injection and 4 h, 1 d, 2 d, 3 d after the second injection. Three days after the second injection, the number of positive cells of cAMP, p-PKA, p-CREB and the number of positive cells of protein co-expression in the right ACC brain area were detected by immunofluorescence, and the relative protein expression of p-PKA and p-CREB were detected by Western blot.

RESULTS

Compared with the control group, the PWTs in the model group decreased significantly 4 h, 3 d and 5 d after the first injection and 1 d, 2 d and 3 d after the second injection (P<0.05); compared with the control group, the positive expression of cAMP, p-PKA and p-CREB in the right ACC brain area in the model group increased significantly (P<0.05), and the number of positive cells of the co-expression of cAMP/p-PKA and p-PKA/p-CREB also increased significantly (P<0.05). Compared with the model group, indomethacin group and sham EA group, the PWTs in the EA group were increased significantly 1 d, 2 d and 3 d after the second injection (P<0.05); compared with the model group, indomethacin group and sham EA group, the positive expression of p-PKA and p-CREB in the right ACC brain area in the EA group decreased significantly (P<0.05), and the number of positive cells of co-expression of cAMP/p-PKA and p-PKA/p-CREB was decreased significantly (P<0.05). Compared with the model group and sham EA group, the positive expression of cAMP in the right ACC brain area was decreased in the EA group (P<0.05).

CONCLUSION

EA have a direct intervention effect on pain memory, which have significant advantage over NSAIDs in the treatment of chronic pain. The advantage effect of EA on pain memory may be related to the inhibition of cAMP/PKA/CREB pathway in ACC area.

[Effect of electroacupuncture on expression of GABAA receptor mRNA in different brain regions in rats with chronic inflammatory pain]

OBJECTIVE

To observe the expression of GABA_A receptor mRNA in different brain regions of the central nervous system in chronic inflammatory pain rats and the intervention effect of electroacupuncture (EA).

METHODS

A total of 48 SPF male SD rats were randomly divided into a blank control group, a model control group, an EA group and a sham EA group, 12 rats in each group. The model of chronic inflammatory pain was established by injecting Freund's complete adjuvant into the foot. The EA group was treated with EA 28 days after the model establishment. The "Housanli" (ST 36) and "Kunlun" (BL 60) were selected and treated with dilatational wave, 2 Hz/100 Hz in frequency, 0.5-1.5 mA for 30 min; EA was given only once. In the sham EA group, the same acupoints were selected but the needles were only inserted into subcutaneous area; EA was connected for 30 min without electrical stimulation. The behavior changes of mechanical pain threshold and thermal pain threshold before model establishment, 1 day, 3 days, 7 days, 14 days, 21 days and 28 days after the model establishment as well as emotional behavior 29 days after the model establishment were observed; the relative expressions of GABA_A receptor mRNA in anterior cingulate cortex, amygdala and hypothalamus were observed.

RESULTS

Compared with the blank control group, the change rates of mechanical pain threshold and thermal pain threshold in the model control group were decreased significantly 1 day, 3 days, 7 days, 14 days, 21 days, 28 days after model establishment (P<0.01); 29 days after model establishment, the movement distance and staying time in the central area of open field test in the model control group were decreased significantly (P<0.05). After EA intervention, compared with the model control group and the sham EA group, the change rates of mechanical pain threshold and thermal pain threshold, as well as the movement distance and the staying time of central area were significantly increased in the EA group (P<0.01, P<0.05). Twenty-nine days after model establishment, the expression of GABA_A receptor mRNA in anterior cingulate cortex and hypothalamus was not significantly different among all groups (P>0.05). Compared with the blank control group, the expression of GABA_A receptor mRNA in the amygdala was decreased significantly in the model control group (P<0.01); compared with the model control group and the sham EA group, the expression of GABA_A receptor mRNA in amygdala was increased after intervention in the EA group (P<0.01).

CONCLUSION

Single treatment of EA could significantly increase the mechanical pain threshold and thermal pain threshold, improve abnormal emotional behavior in rats with chronic inflammatory pain, which may be related to the increasing of expression of GABA_A receptor mRNA in the amygdala.

[Electroacupuncture combined with PNF on proprioception and motor function of lower limbs in stroke patients: a randomized controlled trial]

OBJECTIVE

To observe the clinical efficacy and correlation of electroacupuncture combined with proprioceptive neuromuscular facilitation (PNF) on proprioception and motor function of lower limbs in stroke patients.

METHODS

A total of 96 stroke patients were randomized into an electroacupuncture (EA) group, a PNF group and a combination group, 32 cases in each one. In the EA group, acupuncture was applied at cephalic motor and sensory areas, Huantiao (GB 30), Yanglingquan (GB 34), Xuanzhong (GB 39), Zusanli (ST 36) and Sanyinjiao (SP 6) on affected side, and electroacupuncture was adopted at Yanglingquan (GB 34) and Xuanzhong (GB 39), continuous wave and 2 Hz in frequency for 20 min, once every day. In the PNF group, PNF was performed for 20 min, once a day. In the combination group, electroacupuncture was given before PNF, once a day. 4 weeks as one course and totally 3 courses were required, the effect was followed up after half a year. Before treatment, after 4, 8, 12 weeks of treatment and in follow-up, the average trace error (ATE) and Time, the scores of Fugl-Meyer scale (FMA) and modified Barthel index (MBI) were observed in the 3 groups. Correlation analysis between ATE, Time and FMA was performed.

RESULTS

① The total effective rate in the combination group was 90.3% (28/31), which was superior to 64.5% (20/31) in the EA group and 62.5% (20/32) in the PNF group (P<0.05). ②After 4, 8, 12 weeks of treatment and in follow-up, the ATE and Time in the 3 groups were reduced compared with before treatment (P<0.05, P<0.01). After 8, 12 weeks of treatment and in follow-up, the ATE in the combination group were lower than the EA group and the PNF group (P<0.05, P<0.01). After 12 weeks of treatment and in follow-up, the Time in the combination group were lower than the EA group and the PNF group (P<0.05, P<0.01). ③After 4, 8, 12 weeks of treatment and in follow-up, the FMA scores in the EA group and the combination group were increased compared with before treatment (P<0.01). After 8, 12 weeks of treatment and in follow-up, the FMA scores in the PNF group were increased compared with before treatment (P<0.01). After 8, 12 weeks of treatment and in follow-up, the FMA scores in the combination group were higher than the EA group and the PNF group (P<0.05, P<0.01). ④After 4, 8, 12 weeks of treatment and in follow-up, the MBI scores in the 3 groups were increased compared with before treatment (P<0.01). After 8, 12 weeks of treatment and in follow-up, the MBI scores in the combination group were higher than the EA group (P<0.01). After 12 weeks of treatment and in follow-up, the MBI scores in the combination group were higher than the PNF group (P<0.01). ⑤ The correlation coefficients of ATE, Time and FMA were from 0.4 to 0.75 (P<0.05), suggesting a moderate intensity correlation.

CONCLUSION

Electroacupuncture, PNF and combination therapy can improve proprioception and motor function of lower limbs and activities of daily living, and combination therapy has a better effect. Proprioception and motor function have a strong correlation in the recovery of stroke patients.

[Correlation Between Referred Pain Region and Sensitized Acupoints in Patients with Stable Angina Pectoris and Distribution of Sensitized Spots in Rats with Myocardial Ischemia]

OBJECTIVE

To observe the correlation between the referred pain regions of stable angina pectoris (SAP) and the acupoints in coronary heart disease (CHD) patients and to investigate the rule of regional sensitized point distribution in rats.

METHODS

A total of 1 046 CHD patients with SAP from 8 hospitals in China were recruited in the present study. The tenderness was palpated along the left and right chest, back, shoulder, upper limb, etc. by a specially-assigned researcher in each hospital. Among them, 77 patients accepted pain threshold (PT) measurement by using a hand-held esthesiometer. In animal experiments, 14 SD rats were subjected to occlusion of the left anterior descending branch of the left coronary artery for 4 h for establishing myocardial ischemia (MI) model, and other 4 normal rats were used as the sham-operation control group. Four hours after MI, all the rats accepted tail venous injection of 5% Evans blue (50 mg/kg) for examining the distribution of the blue dye exudation spots at the body surface where the mechanical PT was also detected by a von Frey.

RESULTS

In 1 046 CHD patients, 987 (94.36%) were found to have at least one tenderness spot. The tenderness spots were found at the left chest (87.47%), right chest (13.67%), left arm (ulnar side, 41.30%), right upper limb (4.68%), left shoulder back (30.21%), right shoulder back (7.07%), etc., accompanied with rash or pigmentation, subcutaneous induration, cord-like tissue contracture, skin sag, etc. The mechanical PT level was significantly lower at the tenderness spots of the left upper limb than at non-tender points of the right upper limb in CHD patients (P<0.001). Tenderness and cutaneous abnormal changes in angor pectoris patients distributed mostly on the left chest, back, shoulder and upper limb, and some also on the right. Tender points scattered on, near or outside acupoints. A similar distribution of the blue exudation spots and lower mechanical PT spots were found in MI rats, but not in sham-MI rats.

CONCLUSION

In the case of MI, a regular "referred sensitization" response frequently occurs in the dermatomere area innervated by the corresponding segments (T 1－T 5) in both CHD patients and MI rats, which may be closely associated with the formation of acupoints in ancient China.

[Feasibility of Joint Application of Techniques of Optogenetics and Neuroelectrophysiology to Research of Acupuncture Analgesia]

Since the invention of optogenetic technology, it has greatly promoted the development of neuroscience. Currently, optogenetic approaches have been mostly used to map neural circuits and new neuropharmacology but are rarely seen in the research field of acupuncture analgesia. The mechanism of neural circuits contributing to acupuncture analgesia, an important research hotspot in recent years, has not been fully determined. The optogenetic techniques can be used to modulate and control specific cells, provides highly precise spatial and temporal resolution, is repeatable, and may functionally dissect neuronal networks in vivo. The neuronal activities and their information transmission, processing and storage in intercluster neural networks in different brain regions, and the correlation between behavioral changes and electrical activities of neurons in vivo studies are mainly captured by the implanted microelectropode array, etc. If these two (or more) approaches are combined together, it is definitely and highly helpful to reveal the driving dynamics of neural circuits, plasticity and temporal-spatial activity mode of neurons, as well as behavioral reactions of animals with chronic pain during acupuncture analgesia and may open a new prospect for the application of acupuncture analgesia study.

Suppressing PKC-dependent membrane P2X3 receptor upregulation in dorsal root ganglia mediated electroacupuncture analgesia in rat painful diabetic neuropathy

Painful diabetic neuropathy (PDN) is a common and troublesome diabetes complication. Protein kinase C (PKC)-mediated dorsal root ganglia (DRG) P2X3 receptor upregulation is one important mechanism underlying PDN. Accumulating evidence demonstrated that electroacupuncture (EA) at low frequency could effectively attenuate neuropathic pain. Our previous study showed that 2-Hz EA could relieve pain well in PDN. The study aimed to investigate whether 2-Hz EA relieves pain in PDN through suppressing PKC-mediated DRG P2X3 receptor upregulation. A 7-week feeding of high-fat and high-sugar diet plus a single injection of streptozotocin (STZ) in a dose of 35 mg/kg after a 5-week feeding of the diet successfully induced type 2 PDN in rats as revealed by the elevated body weight, fasting blood glucose, fasting insulin and insulin resistance, and the reduced paw withdrawal threshold (PWT), as well as the destructive ultrastructural change of sciatic nerve. DRG plasma membrane P2X3 receptor level and DRG PKC expression were elevated. Two-hertz EA failed to improve peripheral neuropathy; however, it reduced PWT, DRG plasma membrane P2X3 receptor level, and DRG PKC expression in PDN rats. Intraperitoneal administration of P2X3 receptor agonist αβ-meATP or PKC activator phorbol 12-myristate 13-acetate (PMA) blocked 2-Hz EA analgesia. Furthermore, PMA administration increased DRG plasma membrane P2X3 receptor level in PDN rats subject to 2-Hz EA treatment. These findings together indicated that the analgesic effect of EA in PDN is mediated by suppressing PKC-dependent membrane P2X3 upregulation in DRG. EA at low frequency is a valuable approach for PDN control.

Alleviating Mechanical Allodynia and Modulating Cellular Immunity Contribute to Electroacupuncture's Dual Effect on Bone Cancer Pain

Hypothesis: Electroacupuncture (EA) has been used as an alternative analgesic therapy for hundreds of years, yet its analgesic potency and therapeutic advantage against bone cancer pain (BCP) in comparison with morphine remains unclear. This study aimed to investigate the effects of EA on mechanical allodynia and cellular immunity of BCP rats, and to further explore the potential mechanism. Methods: The BCP model was established by implanting Walker 256 mammary gland carcinoma cells into the left tibia of adult female Sprague-Dawley rats. EA (dilatational wave, 2/100 Hz, 0.5 mA–1mA–1.5 mA for 10 minutes each intensity) was applied bilaterally to Zusanli (ST 36) and Kunlun (BL 60) for 30 minutes. Both EA stimulation and morphine (10 mg/kg, intraperitoneally) was given once every other day. Naloxone (0.3 mg/kg, intraperitoneally) was injected at 30 minutes prior to EA. Mechanical allodynia were demonstrated by paw withdrawal thresholds (PWTs) which measured by dynamic plantar aesthesiometer. T cell proliferation, percentage of CD3⁺, CD4⁺ and CD8⁺ T lymphocytes in spleen as well as expression of interleukin-2 (IL-2) in plasma were detected by WST-8, flow cytometry, and enzyme-linked immunosorbent assay technique, respectively. Results: An intratibial inoculation of Walker 256 mammary gland carcinoma cells significantly decreased PWTs to mechanical stimuli. EA stimulation alleviated mechanical allodynia in BCP rats, and the analgesic potency of EA was weaker than that of morphine. In contrast to morphine, EA stimulation of BCP rats increased splenic concanavalin A (Con A)-induced T cell proliferation and plasma IL-2 content, as well as increased the percentages of splenic CD₃⁺CD₄⁺ and CD₃⁺CD₈⁺ T cell subsets. Moreover, both the analgesic effect and the partial immunomodulation of EA were suppressed by an intraperitoneal injection of naloxone. Conclusion: EA could significantly alleviate BCP-induced mechanical allodynia. Although the analgesic effect of EA was weaker than that of morphine, EA had an immunomodulation effect on cellular immunity. Both analgesic and immunomodulatory effect of EA might share the same mechanism via the opioid-mediated pathway, which needs further investigation.

5-HT in the dorsal raphe nucleus is involved in the effects of 100-Hz electro-acupuncture on the pain-depression dyad in rats

The pain-depression dyad is becoming widespread in the clinic and is attracting increasing attention. A previous study by our group found that 100-Hz electro-acupuncture (EA), but not 2-, 50- and 2/100-Hz EA, was effective against the reserpine-induced pain-depression dyad. This finding is in contrast to the fact that low-frequency EA is commonly used to treat supraspinal-originating diseases. The present study aimed to investigate the mechanism underlying the effects of 100-Hz EA on the pain-depression dyad. Repeated reserpine injection was found to induce allodynia and depressive behaviors in rats. It decreased 5-hydroxytryptamine (5-HT) levels and immunoreactive expressions in the dorsal raphe nucleus (DRN). 100-Hz EA alleviated the pain-depression dyad and upregulated 5-HT in the DRN of reserpine-injected rats. Intracerebroventricular injection of para-chlorophenylalanine, an inhibitor of 5-HT resynthesis, suppressed the upregulation of 5-HT in the DRN by 100-Hz EA and partially counteracted the analgesic and anti-depressive effects of 100-Hz EA. The present study was the first to demonstrate that 5-HT in the DRN is involved in mediating the analgesic and anti-depressive effects of 100-Hz EA on the pain-depression dyad. This finding provided a scientific basis for high-frequency EA as a potential treatment for the pain-depression dyad.

Effect of Electroacupuncture on the NTS is modulated primarily by acupuncture point selection and stimulation frequency in normal rats

Background

The effect of electroacupuncture (EA) is affected by both the acupuncture point selection and the frequency of stimulation. However, little is known regarding acupuncture point and simulation frequency selection. Neuronal activation of the nucleus of the solitary tract (NTS) is one of the important targets of EA for modulating gastrointestinal function. This study investigated the effects of various combinations of EA frequencies and acupuncture points on NTS neurons.

Methods

Rats were randomly divided into normal, 2 Hz EA, 100 Hz EA and the alternate 2/100 Hz EA groups. Then rats in each group were randomly divided into the following two subgroups according to the acupuncture point: ST 36 group and ST 25 group. All the rats underwent electrode implantation surgery. Rats in all EA groups received one treatment with EA (a constant square wave at, 2 Hz,100 Hz or 2/100 Hz frequencies with intensities ranging from 1 to 2 mA), and NTS neuronal activation was recorded before and after EA treatment. Finally, to confirm the effect of EA on the NTS, minimal acupuncture was administered and its effect on NTS was detected.

Results

ST 36 stimulated with 2 Hz EA significantly increased the population of excited NTS neurons and spike frequency. However, ST 36 stimulated with 100 Hz or 2/100 Hz EA produced only a transient effect on the activity of NTS neurons and did not induce any effect on the spike frequency. Furthermore, the excitatory effect of 100 Hz or 2/100 Hz EA on NTS neurons in the ST 36 group was lower than 2 Hz EA at the same point. When applied to ST 25, 2 Hz EA had no significant excitatory effect on NTS neurons or spike frequency. However, 100 Hz EA or 2/100 Hz EA at ST 25 decreased both NTS neuronal excitability and spike frequency. By comparing the effects of different EA combinations, it was shown 2 Hz EA applied to ST 36 had the strongest excitatory effect on NTS neurons, while 100 Hz EA applied to ST 25 had the greatest inhibitory effect. Minimal acupuncture stimulation produced no effect on NTS neurons.

Conclusion

EA’s effects on NTS were mainly affected by the acupuncture point selection, but the frequency of EA also played a role. Different combinations of acupuncture points and frequency selection may lead to different EA effects on NTS neuronal excitability.

[New Trains of Thoughts About Acupuncture Analgesia-Acupuncture Analgesia Feb Involve Multi-dimensional Regulation of Pain]

With the development of pain study, researchers gradually recognized that pain is composed of three main dimensions, namely "sensory-discriminative" "affective-motivational" and "cognitive-evaluative" which influence each other and are also independent from each other. Pain study has shifted away from focusing on the single mode of nociception to the multi-dimensional mode of sensory-affection-cognition. It is held early in traditional Chinese medicine that "when there is a stoppage, there is a pain" and a worsening disease Feb induce depression, which has already shown a multi-dimensional recognition about pain. Acupuncture therapy has been considered to be an effective adjuvant approach for relieving pain. In the present paper, the authors introduced applicability of acupuncture analgesia by modulating the abovementioned multi-dimensions of pain from the following 4 aspects:1) multi-dimensions of pain and related brain regions; 2) recognitions of traditional Chinese medicine about pain; 3) development of researches on acupuncture analgesia, including a) balancing activities of endogenous analgesic and algogenic substances, and triggering intracellular mitogen-activated protein kinase (MAPK) signaling to reduce algesia, b) improving psychological symptoms of patients with depression, anxiety, insomnia, etc., c) modulating functional activities of some common brain regions (as hippocampus, anterior cingutate, frontal lobe of cerebral cortex, etc.) sharing both pain information and learning-memory processing. Hence, the authors hold that if the clinical study and application and experimental researches conducted on the underlying mechanisms of acupuncture analgesia extend towards the multi-dimensions of pain, a series of new concepts or thoughts will be brought out, thereby possibly opening a bright applicable prospect for acupuncture analgesia.

Electroacupuncture treatment partly promotes the recovery time of postoperative ileus by activating the vagus nerve but not regulating local inflammation

Postoperative ileus (POI) after abdominal surgery significantly lowers the life quality of patients and increase hospital costs. However, few treatment strategies have successfully shortened the duration of POI. Electroacupuncture (EA) is a modern way of administering acupuncture and widely used in various gastrointestinal (GI) diseases in the world. Here, we studied the effect of EA on POI and its underlying mechanisms. Intestinal manipulation resulted in significant delays of GI transit, colonic transit and gastric emptying. Surgery also up-regulated c-fos in nucleus of the solitary tract (NTS) and induced inflammation response in the small intestine. Further, operation and inhale anesthesia inhibited NTS neuron excitation duration for the whole observation time. EA administered at ST36 indeed shortened the recovery time of GI and colonic transit, and significantly increased the gastric emptying. EA also significantly activated the NTS neurons after operation. However, there was no anti-inflammation effect of EA during the whole experiment. Finally, atropine blocked the regulatory effect of EA on GI function, when it was injected after surgery, but not before surgery. Thus, the regulatory effect of EA on POI was mainly mediated by exciting NTS neurons to improve the GI tract transit function but not by activating cholinergic anti-inflammatory pathway.

[Suggestions for standardized management of nomenclature and classification of neonatal diseases]

Nomenclature and classification of diseases are not only related to clinical diagnosis and treatment, but also involved in the fields such as management and exchange of medical information, medical expense payments, and medical insurance payment. In order to standardize clinical physicians' diagnostic and treatment activities, medical records, and the first page of medical records, this article elaborates on the basic principles and methods for nomenclature and classification of diseases with reference to international nomenclature of diseases and international classification of diseases. Meanwhile, in view of the problems in clinical practice, this article proposes the classification of neonatal diseases, the basic procedure and writing rules in the diagnosis of neonatal diseases, and death diagnosis principles.

Effect of systemic injection of heterogenous and homogenous opioids on peripheral cellular immune response in rats with bone cancer pain: A comparative study

Exogenous and endogenous opioids have been shown to modulate the immune system. Morphine-induced immunosuppression has been investigated extensively. However, the immune-regulating function of endogenous opioid peptides is unclear. The present study aimed to evaluate the difference in effects on cellular immune function between recombinant rat β-endorphin (β-EP; 50 µg/kg) and plant source morphine (10 mg/kg) via intraperitoneal injection treatment in a rat model of bone cancer pain. Walker 256 cells were injected into a tibial cavity injection to establish the bone cancer pain model. The paw withdrawal thresholds and body weights were measured prior to surgery, at 6 days after surgery, and following 1, 3,6 and 8 treatments. The spleen cells were harvested for detection of T cell proliferation, natural killer (NK) cell cytotoxicity, and the relative quantities of T cell subtypes (CD3⁺, CD4⁺ and CD8⁺ cells). Plasma levels of interleukin-2 (IL-2) were also determined. It was found that single or multiple treatments with β-EP (a homogenous opioid peptide) and morphine (a heterogenous opioid) had good analgesic effects on bone cancer pain, while the analgesia provided by morphine was stronger than that of β-EP. Treatment with β-EP 3, 6 and 8 times increased the body weight gain in the rat model of bone cancer pain, while morphine treatment had on effect on it. With regard to immunomodulatory functions, β-EP treatment increased T cell proliferation and NK cell cytotoxicity, and increased the relative quantities of T cell subtypes, but no effect on T cell secretion. However, morphine treatment decreased T cell proliferation and the levels of T cell subtypes. These data indicate that opioids from different sources have different effects on cellular immune function in vivo. A small dose of homogenous opioid peptide exhibited positive effects (analgesia and immune enhancement) on cancer pain. These results provide experimental evidence supporting the exploitation of human opioids for the treatment of cancer pain.

[Effect of Transcutaneous Electrical Acupoint Stimulation on Post-surgical Gastrointestinal Function, Autonomic Nerve Activities and Plasma Brain-gut Peptide Levels in Patients Undergoing Gastrointestinal Surgery]

OBJECTIVE

To observe the effect of transcutaneous electrical acupoint stimulation (TEAS) on ileus-postope-rative gastrointestinal functions and plasma ghrelin, motilin, and gastrin contents, and heart rate variability (HRV) in patients undergoing gastrointestinal surgery, so as to explore the interaction of vagus-brain-gut peptide.

METHODS

A total of 58 patients undergoing elective gastrointestinal surgery were randomly assigned to TEAS (n=29) and sham-TEAS group (n=29, patients had no subjective sensation to 1 mA TEAS, thus, being considered to be sham-TEAS). TEAS (2 Hz/100 Hz, 6-8 mA for LI 4-PC 6, 12-18 mA for ST 36-SP 6) was applied to bilateral Hegu (LI 4)-Neiguan (PC 6) from 30 min pre-operation to the end of the operation and to bilateral LI 4-PC 6 and Zusanli (ST 36)-Sanyinjiao (SP 6) for 30 minutes twice daily in 3 consecutive post-operative days. ECGs of 12 leads were recorded to analyze different parameters of HRV from 2 days before and 4 days after surgery. Plasma ghrelin, motilin and gastrin contents were assayed by radioimmunoassay, and the patients' first bowel sound, first independent walk, first flatus, first solid food-intake and first defecation were recorded to evaluate the recovery state of gastrointestinal motility.

RESULTS

Postoperative gastrointestinal motility:compared with the sham-TEAS group, the first bowel sound and the first defecation after surgery appeared apparently earlier in the TEAS group (P<0.05), but no significant differences were found between the two groups at the time of the first independent walk, first flatus and the first solid food-intake in patients undergoing gastrointestinal surgery. Plasma brain-gut peptides:the plasma ghrelin and motilin contents 4 days post-surgery were significant increased in the TEAS group than in the sham-TEAS group (P<0.05). No significant difference was found between the two groups in plasma gastrin contents (P>0.05). HRV domains:in comparison with pre-surgery, the levels of low frequency (LF) and high frequency (HF) of frequency domain (FD) and root mean square of successive differences (rMSSD) of the time domain (TD) of HRV 4 days after surgery were significantly decreased in the sham-TEAS group (P<0.05), but no significant changes were found in both FD and TD domains of the TEAS group 4 days after surgery (P>0.05). Compared with the sham-TEAS group, the HF and rMSSD levels were significantly increased in the TEAS group 4 days after the surgery (P<0.05). No significant differences were found between the two groups in the levels of very low frequency, LF and LF/HF levels of FD, and standard deviation of NN (beat-to-beat) intervals, the standard deviation of the average NN intervals and the proportion of NN 50 (the number of pairs of successive NNs that differ by more than 50 ms) divided by total number of NNs of TD.

CONCLUSIONS

TEAS can promote gastrointestinal activities (i.e., reducing the time spending of first bowel sound and the first defecation) in gastrointestinal surgery patients, which may be related to its effects in up-regulating ghrelin and motilin contents and parasympathetic activity.

Changes in amplitude-integrated electroencephalograms in piglets during selective mild head cooling after hypoxia-ischemia

BACKGROUND

Amplitude-integrated electroencephalogram (aEEG) is a simplified, alternative means of monitoring cerebral function and may be more useful clinically in some situations than conventional EEG. The aim of this study is to evaluate newborn piglets as an animal model to examine the effect of selective mild head cooling (HC) on aEEG after hypoxia-ischemia (HI).

METHODS

Thirty-four piglets were randomly allocated to the following treatment groups: normothermic control group (NC, n = 7), selective HC control group (HC, n = 9), normothermic HI group (NHI, n = 9), and selective HC HI group (SHC-HI, n = 9). HI was induced by temporary occlusion of both carotid arteries and simultaneous reduction of the concentration of inspired oxygen to 6% for 30 minutes. Mild hypothermia (35°C) was induced after HI using a HC cap and was maintained for 24 hours. Changes in aEEG were monitored for 6 days after these treatments and the incidence of abnormalities analyzed. Physiological parameters were also measured during this period.

RESULTS

In the two HI groups, animals exhibited severely abnormal aEEGs [continuous low voltage (CLV), burst-suppression, or flat tracing (FT)] 20 minutes after the beginning of HI. At 2 hours, the aEEG returned to normal in most of these animals. From 12 hours to 6 days, all animals in the NHI group exhibited severely abnormal aEEGs. Fewer animals in the SHC-HI group exhibited severe abnormal aEEGs during this time period, and four out of nine (44.4%) animals had continuous normal voltage (CNV) at 6 days.

CONCLUSIONS

Selective mild HC decreases the incidence of severe abnormal aEEGs at late times after HI in newborn piglets.

[Effect of mild and strong manual acupuncture stimulation of "Huantiao" (GB 30) on mechanical pain thresholds and extracellular signal-regulated kinase protein expression in spinal dorsal horns in rats with neuropathic mirror-image pain]

OBJECTIVE

To observe the effect of different intensities of manual acupuncture (MA) stimulation on mechanical pain thresholds (PTs) and the expression of phosphorylated extracellular signal-regulated kinases (p-ERK) in lumbar spinal dorsal horn regions in rats with neuropathic mirror-image pain, so as to explore its mechanisms underlying analgesia.

METHODS

Forty male SD rats were equally and randomly divided into control, spinal nerve ligation (SNL) model, mild MA-stimulation, and strong MA-stimulation groups. Neuropathological pain model was established by ligature of the spinal nerve (L 5). Three days after the SNL, bilateral "Huantiao" (GB 30) were stimulated by rotating the thin (0.22 mm x 13 mm) or thick (0.3 mm x 13 mm) filiform needles at a frequencies of 60 times/min or 180 times/min and at an angle of 180 degrees or 360 degrees for 2 min for rats in the mild and strong MA-stimulation groups, respectively, followed by remaining the needle in place for 30 min. The mechanical PTs were measured before and after SNL. The expression of p-ERK protein in bilateral dorsal horn regions of the lumbar spinal cord (L4- L 6) was detected by Western blot.

RESULTS

In comparison with the control group, the mechanical PTs were significantly decreased beginning from the 3rd day on after SNL on the affected side and from the 7th day on after SNL on the healthy hindpaw (P < 0.05), simultaneously, p-ERK protein expression levels of dorsal horn regions on both sides of the spinal cord were considerably up-regulated on the 12th day (P < 0.05). Compared with the model group, the PTs of the affected hindpaw and the healthy hindpaw were significantly increased on the 7th and 12th day in the strong MA-stimulation group (P < 0.05, P < 0.01), whereas pERK expression levels in the bilateral spinal dorsal horn regions were obviously down-regulated in the strong MA-stimulation group (P < 0.05). No significant differences were found between the model and mild MA-stimulation groups in the PTs of bilateral hindpaws and p-ERK expression levels of the bilateral spinal dorsal horn regions (P > 0.05) except the PTs of the healthy hindpaw on 7th day (P < 0.05).

CONCLUSION

Strong MA-stimulation can alleviate neuropathic mirror-image pain in SNL rats, which is closely related to its effect in down-regulating the expression of p-ERK in the bilateral spinal dorsal horn regions.

[Primary dysmenorrhea treated with staging acupoint catgut embedment therapy: a randomized controlled trial]

OBJECTIVE

To observe the short-term and long-term efficacies on primary dysmenorrhea treated with staging acupoint embedment therapy.

METHODS

Seventy cases of primary dysmenorrhea were randomized into an embedment therapy group and a fenbid group, 35 cases in each one. In the embedment therapy group, the embedment therapy was applied twice during the menstrual cycle, one treatment 3 days before menstruation and one treatment during the 12th-14th days of menstruation, respectively. Guanyuan (CV 4), Zigong (EX-CA 1), Diji (SP 8) and Ciliao (BL 32) were the main acupoints in the treatment 3 days before menstruation. Shenshu (BL 23), Ganshu (BL 18) and Pishu (BL 20) were the main acupoints in the treatment during menstruation. In the fenbid group, fenbid was prescribed for oral administration, 0.3 g each time, twice a day, starting 3 days before menstruation till pain was relieved. The treatment of one menstrual cycle was one session. The continuous treatment of 3 menstrual cycles was required. The short-term and long-term efficacies were evaluated at the end of the 3rd cycle and in 3 months after the treatment terminal. The dysmenorrhea score was used to evaluate the efficacy. Visual analogue scale (VAS) and SF-36 were for the assessment of pain degree and life quality.

RESULTS

(1) The total effective rate was 91.4% (32/35) in the embedment therapy group after the 3 menstrual cycles, which was better than 74.3% (26/35) in the fenbid group (P < 0.01). In the follow-up stage, the total effective rate was 91.4% (32/35) in the embedment therapy group, which was better than 40.0% (14/35) in the fenbid group (P < 0.01). (2) The differences were not significant in dysmenorrhea score and VAS score after the 1st and 2nd menstrual cycle treatments between the two groups (all P > 0.05). In the 3rd menstrual cycle and the follow-up stage, the dysmenorrhea score and VAS score were reduced obviously in the embedment therapy group as compared with those in the fenbid group (P < 0.05, P < 0.01). The rebound effect occurred in the follow-up stage in the fenbid group. (3) In the 3rd menstrual cycle and the follow-up stage, the improvement in the total score of life quality of the embedment therapy group was superior apparently to the fenbid group (P < 0.05, P < 0. 01).

CONCLUSION

The staging acupoint embedment therapy achieves the superior short-term and long-term efficacies as compared with the oral administration of fenbid in the treatment of primary dysmenorrhea. As the symptoms of dysmenorrhea and pain are relieved, the life quality is improved.

[Changes in MLS-BAEP in newborn piglets with hypoxic-ischemic brain damage during selective moderate head cooling therapy]

OBJECTIVE

To study the effect of selective moderate head cooling therapy on maximum length sequences brainstem auditory evoked potential (MLS-BAEP) in newborn piglets with hypoxic-ischemic brain damage.

METHODS

Sixteen newborn piglets aged 5-7 day old were randomly divided into three groups: normothermic control (n=4), HI (n=6) and mild hypothermia-treated (n=6). HI was induced through temporary occlusion of both carotid arteries, followed by mechanical ventilation with low concentration of oxygen (FiO2=0.06) for 30 minutes. Mild hypothermia was induced by equipment via circulating water. MLS-BAER was recorded before HI and at 12 hours, 24 hours, 36 hours, 48 hours, 60 hours, 72 hours, 4 days, 7 days, 10 days, 13 days and 15 days after HI.

RESULTS

Compared with the normothermic control group, all latencies and intervals tended to increase significantly at 72 hours in the HI group and reached peak values on day 7. From day 10, all latencies and intervals tended to decrease, but apart from wave I latency, still differed significantly from those of the normothermic control group. MLS-BAER variables did not reach normal values until day 15. Ⅲ latency, Ⅰ-Ⅲ interval and Ⅰ-Ⅴ interval were significantly reduced in the hypothermia-treated group between 60 and 7 days after HI compared with the HI group (P<0.05). V latency and Ⅲ-Ⅴ interval in the hypothermia-treated group were also reduced compared with the HI group between 72 hours and 7 days after HI (P<0.05).

CONCLUSIONS

Both peripheral and central auditory systems are disturbed by HI, which shows as a significant increase in MLS-BAER variables (all latencies and intervals) in newborn piglets. Involvement in central brainstem auditory system reaches a peak on day 7 after injury. MLS-BAER variables still cannot reach to normal values until day 15. Selective moderate head cooling therapy can significantly reduce brainstem damage induced by HI.

[Controlled observation of the efficacy between floating acupuncture at Tianying point and warm-needling therapy for supraspinous ligament injury]

OBJECTIVE

To compare the efficacy difference in the treatment of supraspinous ligament injury between floating acupuncture at Tianying point and the conventional warm needling therapy.

METHODS

Ninety patients were randomized into a floating acupuncture group and a warm needling group, 45 cases in each one. In the floating acupuncture group, the floating needling technique was adopted at Tianying point. In the warm needling group, the conventional warm needling therapy was applied at Tianying point as the chief point in the prescription. The treatment was given 3 times a week and 6 treatments made one session. The visual analogue scale (VAS) was adopted for pain comparison before and after treatment of the patients in two groups and the efficacy in two groups were assessed.

RESULTS

The curative and remarkably effective rate was 81.8% (36/44) in the floating acupuncture group and the total effective rate was 95.5% (42/44), which were superior to 44.2% (19/43) and 79.1% (34/43) in the warm needling group separately (P < 0.01, P < 0.05). VAS score was lower as compared with that before treatment of the patients in two groups (both P < 0.01) and the score in the floating acupuncture group was lower than that in the warm needling group after treatment (P < 0.01). Thirty-six cases were cured and remarkably effective in the floating acupuncture group after treatment, in which 28 cases were cured and remarkably effective in 3 treatments, accounting for 77.8 (28/36), which was apparently higher than 26.3 (5/19) in the warm-needling group (P < 0.01).

CONCLUSION

The floating acupuncture at Tianying point achieves the quick and definite efficacy on supraspinous ligament injury and presents the apparent analgesic effect. The efficacy is superior to the conventional warm-needling therapy.

[Effects of the renal blood flow at different levels by transcutaneous electrical acupoint stimulation combined general anesthesia induced controlled hypotension]

OBJECTIVE

To observe the intervention of transcutaneous electrical acupoint stimulation (TEAS) on the renal blood flow at different levels of mean arterial pressure (MAP) in controlled hypotension.

METHODS

Forty-two male beagle dogs were randomly divided into seven groups, i. e., the general anesthesia group, the 50% controlled group, the 40% controlled group, the 30% controlled group, the 50% experimental group, the 40% experimental group, and the 30% experimental group, 6 in each group. Beagles in the general anesthesia group were not treated with controlled hypotension, and the target MAP was achieved in those of the rest groups and maintained for 60 min. In the experimental groups, TEAS was applied to bilateral Hegu (LI4), Zusanli (ST36), Sanyinjiao (SP6), and Quchi (LI11) at 2/100 Hz with the stimulation strength of (4 +/- 1) mA starting from the stability of their physiological conditions to 60 min of maintaining the target MAP level. The changes of the renal blood flow were monitored at different time points using laser Doppler.

RESULTS

From starting pressure control to the target MAP level, the renal blood flow was significantly lower in the 30% controlled group than in the general anesthesia group and the basic level of the same group (P < 0.05), while there was no obvious change in the 30% experimental group. In maintaining the blood pressure, the renal blood flow was significantly lower in the 50% controlled group, the 40% controlled group, the 30% controlled group, and the 30% experimental group than in the general anesthesia group (P < 0.05), while there was no obvious change in the 50% experimental group or the 40% experimental group. By the end of blood pressure recovery, the renal blood flow restored to the basic level in the 50% controlled group, the 50% experimental group, and the 40% experimental group (P > 0.05), while it was not restored to the basic level in the 40% controlled group, the 30% controlled group, and the 30% experimental group (P < 0.05).

CONCLUSION

TEAS combined general anesthesia in controlled hypotension could effectively improve the renal blood flow, thus protecting the kidney.

[Effects of transcutaneous electrical acupoint stimulation combined with general anesthesia for controlled hypotension on heart function and oxidation resistance of myocardium]

OBJECTIVE

To investigate the intervention effect of transcutaneous electrical acupoint sitmulation (TEAS) on heart under limiting level of controlled hypotension.

METHODS

Eighteen male Beagles were randomly divided into a general anesthesia group, a control group and an experimental group, 6 dogs in each group. All animals were applied with general anesthesia, and the animals of the control group and the experimental group were administered with combination of isoflurane and sodium nitroprusside (SNP) for controlled hypotension to 30% mean arterial pressure (30% MAP) of base line for 60 min. In the experimental group, TEAS (2 Hz/100 Hz, 6-8 mA) was applied to "Hegu" (LI4), "Zusanli" (ST 36), "Sanyinjiao" (SP 6) and "Quchi" (LI 11) from the beginning of physiological conditions stability to the end of maintained low MAP for 60 min. Creatine kinase isoenzymes MB (CK-MB) and lactate dehydrogenase (LDH) activity were detected at the base line and 2 h, 24 h, 48 h, 72 h after operation. Total superoxide dismutase (T-SOD) and malondialdehyde (MDA) in myocardium were observed at 72 h after operation.

RESULTS

The peak of LDH arrived at 24 h after operation and then restored in 3 groups. Compared with basal level, the activity of LDH in controlled group at 72 h after operation was significantly increased (P < 0.05), and in the other two groups no obvious change (P > 0.05). The activity of CK-MB arrived to peak from 2 h to 24 h after operation, and then came back gradually in 3 groups. Compared with postoperative 72 h of the same group, the control group at 48 h significantly increased (P < 0.05), while the other two groups had no statistically significant difference (P > 0.05). The content of MDA at 72 h after operation in controlled group was higher significantly than that in the general anesthesia group and the experimental group (both P < 0.05).

CONCLUSION

TEAS combined with anesthesia for controlled hypotension can elevate myocardial effect of anti-oxide free radical, reduce the postoperative release of LDH and CK-MB, so as to produce myocardial protection.

Cerebral palsy in children: movements and postures during early infancy, dependent on preterm vs. full term birth

BACKGROUND

A deviant motor behaviour at age 3 to 5 months is predictive of cerebral palsy (CP). Particular features of the early motor repertoire even proved predictive of the degree of functional limitations as classified on the Gross Motor Function Classification System (GMFCS) in children with CP, born preterm.

AIMS

We aimed to determine whether an association between the early motor repertoire and the GMFCS also holds true for children born at term.

STUDY DESIGN

Longitudinal study.

SUBJECTS

79 infants (60 boys and 19 girls; 47 infants born at term; video recorded for the assessment of movements and posture at age 9 to 20 weeks postterm age) who developed CP.

OUTCOME MEASURES

The GMFCS was applied at age 2 to 5 years.

RESULTS

Motor optimality at age 3 to 5 months showed a significant correlation with functional mobility and activity limitation as classified on the GMFCS at age 2 to 5 years in both children born at term (Spearman rho=-0.66, p<0.001) and born preterm (rho=-0.37, p<0.05). Infants born preterm were more likely to show normal movement patterns than infants born at term. A normal posture and an abnormal, jerky (yet not monotonous) movement character resulted in better levels of function and mobility. With the exception of one, none of the infants showed fidgety movements. A cramped-synchronised movement character, repetitive opening and closing of the mouth, and abnormal finger postures characterised children who would show a poor self-mobility later.

CONCLUSIONS

Assessing the quality of motor performance at 9 to 20 weeks postterm age (irrespective of the gestational age) improves our ability to predict later functional limitations in children with CP.

[Effects of transcutaneous electrical acupoint stimulation combined general anesthesia in controlled hypotension at different levels on the liver blood flow ]

OBJECTIVE To observe the changes of the liver blood flow in controlled hypotension by transcutaneous electrical acupoint stimulation (TEAS) combined general anesthesia, thus clarifying the mechanism of liver protection effect in acupuncture anesthesia combined with drugs.

METHODS

Forty-two male beagles were randomly divided into seven groups, i.e. , the general anesthesia group, the 50% control group, the 50% experiment group, the 40% control group, the 40% experiment group, the 30% control group, and the 30% experiment group, 6 in each group. Beagles in the latter six groups were administered with isoflurane inhalation and intravenous dripping of sodium nitroprusside (SNP) for controlled hypotension. The mean arterial pressure (MAP) was lowered to 50%, 40%, and 30% basic MAP and lasted for 60 min. Beagles in the general anesthesia group was not treated with controlled hypotension. In the experiment groups, TEAS was applied to bilateral Hegu (LI4), Zusanli (ST36), Sanyinjiao (SP6), and Quchi (LI11) at 2/100 Hz with the stimulation strength of 4 +/- 1 mA. The TEAS started from the stability of physiological conditions to 60 min after maintaining the target MAP. The changes of blood flow of the liver tissue surface at corresponding time points were monitored by laser Doppler blood flow meter.

RESULTS

Between the beginning of hypotension and the maintaining stage of target low blood pressure, the liver blood flow of the 50% control group was significantly lower than the level of the general anesthesia group and the basic level at corresponding time points (P < 0.05). It was significantly reduced in the 50% experiment group only at 30-60 min of maintenance. Besides, in the early period of maintenance (10-30 min), it was significantly higher in the 50% experiment group than in the 50% control group at the same time points (P < 0.05). In this stage, there was no obvious increase in the liver blood flow in the 40% and 30% experiment groups. In the recovery phase of blood pressure (20-30 min), the liver blood flow of the 40% experiment group had been restored to the level of the 40% control group and the basic level, while it had not been restored in the general anesthesia group. In this stage, the similar changing tendency of the liver blood flow occurred in the 50% and 30% experiment groups and the 50% and 30% control groups.

CONCLUSIONS

Line to a high level of controlled hypotension (50%), TEAS liver protective effect was obviously embodied in the early step-down phase and the maintenance phase. Line-induced hypotension to a lower level (40%), TEAS liver protective effect was obviously embodied in the recovery phase.

Changes in gastric blood flow in dogs undergoing transcutaneous electrical acupoint stimulation combined with general anesthesia for controlled hypotension

AIM: To observe the changes in gastric blood flow in dogs undergoing controlled hypotension by transcutaneous electrical acupoint stimulation (TEAS) combined with general anesthesia, so as to clarify the mechanism of gastro-protective effect of acupuncture-drug compound anesthesia.

METHODS: Fifty-four male beagles were randomly and equally divided into nine groups: simple anesthesia group, 60% control group, 60% experiment group, 50% control group, 50% experiment group, 40% control group, 40% experiment group, 30% control group, and 30% experiment group. General anesthesia was induced in all dogs by isofluane inhalation. Controlled hypotension was achieved in all the groups except for the simple anesthesia group to lower the mean arterial pressure (MAP) to 60%, 50%, 40%, and 30% of basic MAP and maintain at that level for 60 min. TEAS was applied in the experimental groups. The changes in gastric blood flow at various time points were monitored using a laser Doppler blood flow meter.

RESULTS: At the time of target blood pressure level of controlled hypotension (T0), the levels of gastric blood flow in all control groups were significantly lower than baseline level (all P < 0.05), while the 60% (P = 0.316) and 50% (P = 0.539) experiment groups showed no significant decrease in gastric blood flow. After maintaining target blood pressure level for 10 min (T1), except for the 50% experiment group (P = 0.089 vs baseline level, P = 0.140 vs simple anesthesia group, P < 0.05 vs control groups), the levels of gastric blood flow in other pressure-controlling groups were significantly lower than baseline levels and those in the general anesthesia group at the same time points (all P < 0.05). At the stage of blood pressure recovery, the levels of gastric blood flow in the 50% (P = 0.174), 30% (P = 0.071) and 40% (P = 0.084) experiment groups had returned to baseline level, while this did not occur in the control groups.

CONCLUSION: Gastro-protective effect of TEAS is apparent in case of mild blood pressure control (50% MAP) but is not obvious in case of strong blood pressure control (30% MAP) . TEAS can promote the rapid recovery of gastric blood flow at the stage of blood pressure recovery.

Effects of hypothermia on brain injury induced by status epilepticus

We investigated the neuroprotective efficacy of hypothermia after status epilepticus (SE) in immature rats. In addition, the expression levels of NMDAR1 and c-Jun were measured to establish a possible signaling mechanism for hypothermia-induced neuroprotection. Pilocarpine-treated rats were randomly divided into 2 groups: group D (diazepam) and group DH (diazepam plus hypothermia). Compared to the control (group NS) rats, Pilocarpine-induced SE significantly enhanced the expression of NMDAR1 and c-Jun in the hippocampus, and also significantly increased the numbers of necrotic and apoptotic pyramidal neurons. The DH group exhibited significantly fewer necrotic and apoptotic hippocampal pyramidal neurons and reduced NMDAR1 expression than group D. In contrast, early expression of c-Jun was significantly higher in the hippocampi of hypothermia-treated rats than in the hippocampi of group D, while late c-Jun expression was significantly lesser than group D. Our results show mild post-ictal hypothermia partially rescues neuronal cell death in the hippocampus following SE. We further suggest that elevated NMDAR1 expression exacerbates SE-induced neuronal death in pilocarpine-treated rats, while early c-Jun overexpression, concomitant with hypothermia, suppresses subsequent neuronal death.

[Effect of pre-electroacupuncture at "Zusanli" (ST 36) on DA and 5-HT contents and their ratio in hypothalamus and striatum in exercise rats]

OBJECTIVE

To observe anti-fatigue effect and mechanisms of pre-electroacupuncture (EA) at "Zusanli" (ST 36) in rats undergoing acute treadmill running.

METHODS

Fifty male SD rats were randomly divided into three groups: a quiet group (group Q, n = 10), a model group (group M, n = 20) and an EA preconditioning group (group EAP, n = 20). After adaptation for undergoing treadmill running, all the rats in group M and group EAP were trained on acute treadmill running. Besides, EA with continuous waves, 2 Hz in frequency and 2 mA in intensity was applied at bilateral "Zusanli" (ST 36) for 30 min, which was applied once daily for continuous 6 days before treadmill running for the rats in Group EAP. Plasma lactate contents were measured immediately and 3 hours after treadmill running, respectively. Changes of dopamine (DA) and serotonin (5-HT) contents obtained immediately and 3 hours after treadmill running, respectively, in hypothalamus and striatum, were detected and compared, and DA/5-HT ratios were calculated.

RESULTS

Compared with group Q, the levels of blood lactate and hypothalamic 5-HT tented to increase in rats of group M, and the contents of hypothalamic DA increased significantly (P < 0.01), while the contents of striatal DA and 5-HT in group M decreased significantly (both P < 0.01) at 3 h after treadmill running. Immediately after treadmill running, the contents of DA and 5-HT increased significantly in hypothalamus (both P < 0.01), but decreased significantly in striatum (both P < 0.01) in group EAP, compared with those in group M. Moreover, EA pretreatment markedly decreased the levels of blood lactate (P < 0.05) and hypothalamic 5-HT (P < 0.01), and obviously elevated the ratio of DA/5-HT in the hypothalamus (P < 0.01) at 3 h after treadmill running.

CONCLUSION

Preventive EA at "Zusanli" (ST 36) can accelerate recovery from fatigue, which may be related to its reducing accumulation of blood lactate, elevating DA/ 5-HT ratio in the hypothalamus of the rats undergoing treadmill running.

[Effects of transcutaneous electrical acupoint stimulation combined with general anesthesia on changes of gastric dynamics in controlled hypotension dogs]

OBJECTIVE

To observe the effect of transcutaneous electrical acupoint stimulation (TEAS) combined with general anesthesia on gastric dynamics in controlled hypotension dogs, so as to provide experimental evidence for compound acupuncture anesthesia.

METHODS

Eighteen male beagle dogs were randomly divided into general anesthesia group (GA group, n = 6), general anesthesia + controlled hypotension group (GA + OHT group, n = 6) and general anesthesia combined with TEAS + controlled hypotension group (TEAS group, n = 6). The latter two groups were administered with the same anesthetics [isofluane inhalation and intravenous sodium nitroprusside (SNP)] for inducing controlled hypotension (being the 40% of the baseline level). Beagles of the GA group were not treated with controlled hypotension (the initial concentration of SNP = 1 microg/kg x min(-1), and with an increase rate of 1 microg/kg x min(-1) until the controlled hypotension phase). In the TEAS group, TEAS [2 Hz/100 Hz, (4 +/- 1) mA]was applied to "Quchi" (LI 11) , "Zusanli" (ST 36), "Hegu" (LI 4), and "Sanyinjiao" (SP 6) from the beginning of the stable physiological condition phase to the end of the controlled-low mean arterial pressure (MAP) phase. Electrogastrogram (EGG) was recorded, and serum gastrin (GAS) and motilin (MTL) contents were detected by enzyme-linked immunosorbent assay.

RESULTS

Compared with the basic level, the amplitude value of EGG at 60 mm after controlled hypotension in the GA + CHT group was significantly lower (P < 0.05), while the amplitude level of EGG of the TEAS group at the time-point of MAP recovery was significantly higher than those of the GA and GA + CHT groups (P < 0.05). No significant changes were found among the 3 groups in the frequency levels of EGG. At the time-points of MAP recovery and 2 h after MAP recovery, serum MTL and GAS levels in the TEAS group were close to their basic level (P > 0.05), and serum GAS level at the time-point of 2 h after MAP recovery in the TEAS group was considerably higher than those in the GA and GA + CHT groups (P < 0.05). Twenty-four, 48 and 72 h after MAP recovery, serum GAS levels in the TEAS group were moderately (24 h and 48 h ) and significantly (72 h) higher than that of the basic level. No significant differences were found between the GA and GA + CHT groups in serum MTL and GAS levels at the time-points of 2, 24, 48 and 72 h after MAP recovery (P > 0.05).

CONCLUSION

TEAS combining with general anesthesia for controlled hypotension can improve the amplitude of EGG, and serum MTL and GAS contents, favoring the recovery of gastric dynamics and the functional protection of stomach.

[Cardiac protective effects of transcutaneous electrical acupoint stimulation combined with general anesthesia for controlled hypotension]

OBJECTIVE

To explore the protective effect and the mechanism of controlled hypotension induced by transcutaneous electrical acupoint stimulation (TEAS) combined with general anesthesia.

METHODS

Sixteen male Beagles were randomly divided into a group of controlled hypotension induced by simple general anesthesia (control group) and a group of controlled hypotension induced by TEAS combined with general anesthesia (observation group). All the animals were administered with combination of Isoflurane and Sodium Nitroprusside (SNP) for controlled hypotension without TEAS until the arterial pressure was lowered to 30% basic mean arterial pressure (MAP) for 60 min. In the observation group, TEAS (2 Hz/100 Hz, 3-5 mA) was applied to "Hegu" (LI 4) "Zusanli" (ST 36), "Sanyinjiao" (SP 6) and "Quchi" (LI 11) from the beginning of physiological conditions stability to the end of maintained low MAP for 60 min, but there was no TEAS in control group. The changes of MAP, the left intraventricular pressure (LIVP), T wave and ST-T segment of II lead electrocardiogram (ECG) were monitored with the physiological signal acquisition system, and myocardial apoptosis was detected by TUNEL method.

RESULTS

All the animals could maintain stable required low blood pressure. At one hour after cease of controlled hypotension, MAP of (109.56 +/- 6.14) mmHg returned to the basic level in the observation group, while MAP of (84.91 +/- 6.36) mmHg was still lower than its basic MAP of (111.02 +/- 4.15) mmHg in the control group (P < 0.05), showing significant difference in MAP between the two groups (P < 0.05). -dp/dtmax of (3156.32 +/- 332.82) mmHg/s showed significant lower than its basic value of (4585.33 +/- 638.55) mmHg/s when blood pressure increased for 1 h in the control group (P < 0.05), but there was no difference in the observation group. When the objective low MAP maintaining for 60 min the ST segment was decreased significantly in the control group (P < 0.05), but there was no difference in the observation group. The numbers of positive apoptosis cardiocytes in the observation group were (24.67 +/- 2.45) cells/mm2, which were significantly fewer than (37.89 +/- 1.90) cells/mm2 in the control group (P < 0. 05).

CONCLUSIONS

TEAS combined with general anesthesia for controlled hypotension can significantly shorten restoration time of MAP, help to improve myocardial ischemia and the cardiac functional recovery and reduce myocardial apoptosis so as to produce myocardial protection.

[Effect of electroacupuncture at "Zusanli" (ST 36) and "Sanyinjiao" (SP 6) on collagen-induced arthritis and secretory function of knee-joint synoviocytes in rats]

OBJECTIVE

To observe the effect of electroacupuncture (EA) of "Zusanli" (ST 36) and "Sanyinjiao" (SP 6) on collagen-induced arthritis (CIA) and its underlying mechanism in regulating the secretory function of knee-joint synovial cells in CIA rats.

METHODS

Thirty-six Wistar rats were equally randomized into control, model and EA groups. CIA model (rheumatoid arthritis) was duplicated by intradermal injection of Bovine type II collagen into the back of the anesthetized rats. EA (2 Hz, 2 mA) was applied to "Zusanli" (ST 36) and "Sanyinjiao" (SP 6) for 30 min, once a day for 30 days. The paw volume was measured by using a Plethysmometer and hot water tail-flick tests (50 degrees C) were conducted for detecting the rats' pain threshold (PT) before and after the treatment. The contents of PGE2, IL-1beta and TNF-alpha in supernatant of the cultured joint synoviocytes were detected by enzyme linked immunosorbent assay (ELISA).

RESULTS

In comparison with control group, the swelled paw volume, the declined PT, PGE2, TNF-alpha and IL-1beta contents in knee-joint synoviocyte supernatant were significantly higher in model group (P < 0.05). Compared with model group, PT increased obviously (P < 0.05); paw volume, supernatant PGE2, TNF-alpha and IL-1beta contents decreased obviously (P < 0.05) in EA group.

CONCLUSION

EA of ST 36 and SP 6 has a pronounced therapeutic effect in relieving knee joint pain and inflammation in CIA rats, which may be related to its effect in regulating the secretory function of the knee-joint synoviocytes.

[Value of maximum length sequences brainstem auditory evoked potential in neonatal asphyxia]

OBJECTIVE

To study the value of a new technique, maximum length sequences brainstem auditory evoked potential (MLS BAEP), in the assessment of the severity of brain damage following asphyxia in term neonates.

METHODS

One hundred and three neonates with perinatal asphyxia and 26 normal term neonates were eligible for the study. Conventional and MLS BAEP examinations were performed within three days after birth. Of the 103 neonates with asphyxia, 17 did not suffer from HIE, 37 had mild HIE, 31 had moderate HIE, and 18 had severe HIE. The latencies and amplitudes of waves I, III and V, and the inter-peak intervals of I-III, III-V, and I-V were analyzed.

RESULTS

The latencies of wave V and the inter-peak intervals of I-III, III-V and I-V prolonged gradually with the more severe HIE in both the MLS and the conventional BAEP (P<0.05 or 0.01). The differences among groups were more significant with the increasing repetition rate of click in the MLS BAEP. Compared with the normal controls, conventional BAEP did not show prolonged intervals of I-III and III-V in the mild HIE subgroup, and a prolonged inter-peak interval of III-V in the moderate HIE subgroup, while the MLS BAEP showed significantly prolonged inter-peak intervals of I-III and III-V in the three HIE subgroups and the differences were more and more significant as an increase in the repetition rate of click from 91 to 910 times/seconds.

CONCLUSIONS

MLS BAEP is more sensitive and valuable than the conventional one in detecting hypoxic-ischemic brain damage following asphyxia by increasing the repetition rate of click. MLS BAEP provides a new measurement in quantity to assess the severity of HIE in neonates with perinatal asphyxia.

[Neurodevelopmental outcome of preterm infants discharged from NICU at 1 year of age and the effects of intervention compliance on neurodevelopmental outcome]

OBJECTIVE

To investigate the neurodevelopmental outcome of preterm infants who were discharged from neonatal intensive care unit (NICU) at 1 year of age and the impact factors contributing to the neurodevelopmental outcome and to study whether early intervention can improve the neurodevelopmental outcome in preterm infants.

METHODS

Early intervention guidance and follow-up visits were performed after the preterm infants discharged from NICU. The infants received the infant development test of Child Development Centre of China (CDCC) for neurological development at 1 year of age. The neurodevelopmental outcome was evaluated based on mental development index (MDI) and physical development index (PDI). MDI and PDI > 85 was defined as normal, MDI or PDI between 70 and 85 as critical and MDI or PDI < 70 as abnormal. Social-domestic and clinical factors related to neurological development were analyzed by ANOVA or chi-square test. Potential high risk factors were analyzed with logistic regression. To investigate the effects of intervention compliance on neurological development, the infants were classified into two groups according to different intervention compliances. The good compliance group included infants who received a through familial intervention for more than 4 days weekly (30 minutes daily) and consulted with physicians more than 5 times in 1 year. The infants who did not receive the interventions as the good compliance group served as the bad compliance group.

RESULTS

This study consisted of 210 infants, with a mean gestational age of 33.2 +/- 2.6 weeks and a mean birth weight of 1923.3 +/- 558.8 g. Normal, critical and abnormal neurological development occurred in 123 cases (58.6%), 61 cases (29.0%) and 26 cases (12.4%) respectively. Eighteen infants (8.6%) had mental lag and 9 (4.3%) had cerebral palsy (CP). The MDI and PDI scores of the good compliance group (111 cases) were 97.15 +/- 17.38 and 94.23 +/- 18.55 respectively, which were markedly higher than those of the bad compliance group (89.87 +/-18.92 and 87.20 +/-19.12; P < 0.05). The incidence of CP (3/111, 2.7%) in the good compliance group was lower than that of the bad compliance group (5/99, 6.1%) although there were no statistical differences. Parents' education level, multiple birth, serious intracranial hemorrhage and apnea were risk factors for adverse neurodevelopmental outcome.

CONCLUSIONS

Preterm infants discharged from NICU are a high risk group of neurodevelopmental disablement. Early intervention can improve the neurodevelopmental outcome of perterm infants at high risk.

[Mild hypothermia attenuates neuronal apoptosis after cerebral hypoxia-ischemia in neonatal rats]

OBJECTIVE

To investigate the effects of mild hypothermia on sequential events of neuronal apoptosis following hypoxic-ischemic brain damage (HIBD) in neonatal rats.

METHODS

A model of HIBD was prepared by ligating the left common carotid artery in 7-day-old rats, followed by 8% hypoxia exposure. HIBD rats were randomly assigned into a hypothermia group (rectal temperature = 33 centi-degrees) and a normothermia group (rectal temperature = 36 centi-degrees). TUNEL, Haematoxylin and Eosin, and Nissl staining were used to detect neuronal apoptosis. Western blotting, RT-PCR and enzyme activity measurement were used to evaluate the changes of plasma and mitochondrial cytochrome c (Cyt c), caspase-3 mRNA expression and caspase-3 enzyme activity, respectively.

RESULTS

The number of apoptotic cells in the ipsilateral hemisphere of the hypothermia group was significantly reduced compared with that of the normothermia group at 72 hrs post-HI (6.4 +/- 1.7% vs 25.3 +/- 1.5%) (P < 0.01). Analysis of Western blotting showed that Cyt c levels increased in the cytosolic fraction, but decreased significantly in the mitochondrial fraction in the ipsilateral hemisphere of the hypothermia group at 24, 48 and 72 hrs of HI insult compared with the normothermia group (P < 0.05). Caspase-3 mRNA increased significantly after 24 hrs post-HI in the normothermia group, and this change became more pronounced with time. Mild hypothermia treatment decreased significantly caspase-3 mRNA expression at 24, 48 and 72 hrs post-HI (P < 0.05). Caspase-3 activity gradually increased 2 hrs after HI insult and peaked at 24 hrs in the normothermia group. Mild hypothermia treatment resulted in a significant reduction in caspase-3 activity in the ipsilateral hemisphere, with an optimal effect produced at 24 hrs post-HI (2.42 +/- 0.5 RFU vs 34.7 +/- 3.2 RFU; P < 0.01).

CONCLUSIONS

Mild hypothermia treatment attenuates neuronal apoptosis following HIBD, possibly through a reduction in Cyt c release from mitochondria and an inhibition of caspase-3 mRNA expression and its enzyme activity.

[Effects of inhaled nitric oxide on lung function in ventilated premature piglets]

OBJECTIVE

To investigate the efficacy of nitric oxide (NO) inhalation on lung function and modulation of inflammation in ventilated premature piglets.

METHODS

Premature piglets were obtained at gestation of 101-103 days (89% of full term) with a mean body weight of 870 g. All animals were subjected to mechanical ventilation (PEEP 4-6 cmH2O, Vt 6-8 mL/kg, RR 40-60/min) and randomized into 4 group (n=8 each): Ventilation control, NO inhalation (5-10 ppm), Surfactant (100 mg/kg) or NO plus surfactant. Before and during the ventilation blood gas and lung mechanics were monitored. At the end of the experiment, the lung samples were taken for measuring the NF-kappaB activity, wet/dry weight ratio and histopathology, and the results were compared with those from 10 non-ventilated premature piglets.

RESULTS

The oxygenation index was significantly lower in the NO+surfactant-treated group compared with that of the Control group (2.3 +/- 1.9 vs 9.5 +/- 7.5, P < 0.05). The alveolar aeration in the lungs was similar among the treatment groups. Both NO and NO+surfactant treatments significantly improved the ventilation index. The NO-treated and the Non-ventilated groups had a significantly lower NF-kappaB activity and wet/dry lung weight ratio compared with the Control group. Neither methemoglobin and NO2 levels nor inflammatory lung injury was significantly increased in the NO and combined with surfactant-treated groups.

CONCLUSIONS

Early treatment with NO alone or combined with surfactant can improve oxygenation and ventilation efficacy without obvious adverse effects on immature lungs of premature piglets. The beneficial effects of NO may be due to the suppression of NF-kappaB activity.

Cholinergic neurotransmission in the preBötzinger Complex modulates excitability of inspiratory neurons and regulates respiratory rhythm

We investigated whether there is endogenous acetylcholine (ACh) release in the preBötzinger Complex (preBötC), a medullary region hypothesized to contain neurons generating respiratory rhythm, and how endogenous ACh modulates preBötCneuronal function and regulates respiratory pattern. Using a medullary slice preparation from neonatal rat, we recorded spontaneous respiratory-related rhythm from the hypoglossal nerve roots (XIIn) and patch-clamped preBötC inspiratory neurons. Unilateral microinjection of physostigmine, an acetylcholinesterase inhibitor, into the preBötC increased the frequency of respiratory-related rhythmic activity from XIIn to 116+/-13% (mean+/-S.D.) of control. Ipsilateral physostigmine injection into the hypoglossal nucleus (XII nucleus) induced tonic activity, increased the amplitude and duration of the integrated inspiratory bursts of XIIn to 122+/-17% and 117+/-22% of control respectively; but did not alter frequency. In preBötC inspiratory neurons, bath application of physostigmine (10 microM) induced an inward current of 6.3+/-10.6 pA, increased the membrane noise, decreased the amplitude of phasic inspiratory drive current to 79+/-16% of control, increased the frequency of spontaneous excitatory postsynaptic currents to 163+/-103% and decreased the whole cell input resistance to 73+/-22% of control without affecting the threshold for generation of action potentials. Bath application of physostigmine concurrently induced tonic activity, increased the frequency, amplitude and duration of inspiratory bursts of XIIn motor output. Bath application of 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP, 2 microM), a M3 muscarinic acetylcholine receptor (mAChR) selective antagonist, increased the input resistance of preBötC inspiratory neurons to 116+/-9% of control and blocked all of the effects of physostigmine except for the increase in respiratory frequency. Dihydro-beta-erythroidine (DH-beta-E; 0.2 microM), an alpha4beta2 nicotinic receptor (nAChR) selective antagonist, blocked all the effects of physostigmine except for the increase in inspiratory burst amplitude. In the presence of both 4-DAMP and DH-beta-E, physostigmine induced opposite effects, i.e. a decrease in frequency and amplitude of XIIn rhythmic activity. These results suggest that there is cholinergic neurotransmission in the preBötC which regulates respiratory frequency, and in XII nucleus which regulates tonic activity, and the amplitude and duration of inspiratory bursts of XIIn in neonatal rats. Physiologically relevant levels of ACh release, via mAChRs antagonized by 4-DAMP and nAChRs antagonized by DH-beta-E, modulate the excitability of inspiratory neurons and excitatory neurotransmission in the preBötC, consequently regulating respiratory rhythm.

One-third of term babies after perinatal hypoxia-ischaemia have transient hearing impairment: dynamic change in hearing threshold during the neonatal period

AIM

To examine the process of change in hearing threshold during the neonatal period after perinatal hypoxia-ischaemia.

METHODS

The threshold of brainstem auditory evoked responses (BAER) was measured serially during the first month after birth in 92 term babies who suffered hypoxia-ischaemia.

RESULTS

The mean BAER threshold in these babies was significantly increased on day 1 (ANOVA p < 0.001). The elevated threshold decreased progressively on days 3 and 5, but was still significantly higher than that in normal controls (p < 0.01). The elevation continuously decreased more slowly on days 10 and 15, and to a near normal level on day 30. Threshold elevation was seen in 31.7% of the babies on day 1, and 34.5% during the first three days. The rate of elevation decreased progressively thereafter. On day 30, 10.6% of the subjects still had increased thresholds. Moderate to severe elevation occurred mainly during the first week and severe elevation occurred predominately on day 1. Threshold elevation starting after days 3-5 is likely to be due to middle-ear disorders. As a whole, during the first month, 44.6% (41/92) of the babies studied had threshold elevation. BAER threshold was correlated weakly with the stage of hypoxic-ischaemic encephalopathy on days 1 and 3. The threshold was significantly higher in babies with severe encephalopathy than in those with mild or moderate encephalopathy during the first 3 d of life.

CONCLUSION

Hearing threshold is elevated in about one-third of term babies after hypoxia-ischaemia. The elevated threshold decreases progressively after birth, and returns to normal by one month in most babies. The threshold correlates weakly with the severity of encephalopathy.

Insulin-like growth factor (IGF)-1 suppresses oligodendrocyte caspase-3 activation and increases glial proliferation after ischemia in near-term fetal sheep

Insulin-like growth factor (IGF-1) markedly increases myelination and glial numbers in white matter after ischemia in near-term fetal sheep; however, it is unclear whether this is due to reduced cell loss or increased secondary proliferation. Brain injury was induced in near-term fetal sheep by 30 minutes of bilateral carotid artery occlusion. Ninety minutes after the occlusion, fetuses were given, intracerebroventricularly, either a single dose of IGF-1 (either 3 or 30 micro g), or 3 micro g followed by 3 micro g over 24 hours (3 + 3 micro g). White matter was assessed 4 days after reperfusion. Three micrograms, but not 30 micro g of IGF-1 prevented loss of oligodendrocytes and myelin basic protein density (P < 0.001) compared to the vehicle-treated ischemia controls. No additional effect was observed in the 3 + 3 micro g group. IGF-1 treatment was associated with reduced caspase-3 activation and increased glial proliferation in a similar dose-dependent manner. Caspase-3 was only expressed in oligodendrocytes that showed apoptotic morphology. Proliferating cell nuclear antigen co-localized with both oligodendrocytes and astrocytes and microglia. Thus, increased oligodendrocyte numbers after IGF-1 treatment is partly due to suppression of apoptosis, and partly to increased proliferation. In contrast, the increase in reactive glia was related only to proliferation. Speculatively, reactive glia may partly mediate IGF-1 white matter protection.

RT-PCR reveals muscarinic acetylcholine receptor mRNA in the pre-Bötzinger complex

Muscarinic receptors mediate the postsynaptic excitatory effects of acetylcholine (ACh) on inspiratory neurons in the pre-Bötzinger complex (pre-BötC), the hypothesized site for respiratory rhythm generation. Because pharmacological tools for identifying the subtypes of the muscarinic receptors that underlie these effects are limited, we probed for mRNA for these receptors in the pre-BötC. We used RT-PCR to determine the expression of muscarinic receptor subtypes in tissue punches of the pre-BötC taken from rat medullary slices. Cholinergic receptor subtype M(2) and M(3) mRNAs were observed in the first round of PCR amplification. All five subtypes, M(1)-M(5), were observed in the second round of amplification. Our results suggest that the majority of muscarinic receptor subtypes in the pre-BötC are M(2) and M(3), with minor expression of M(1), M(4), and M(5).