Objective: To investigate whether hyperbaric oxygen therapy(HBOT) can improve the peripheral neuropathy in streptozotocin-induced diabetic rats, and to study its possible mechanisms. Method: The diabetic rat model was induced by injection intraperitonally of streptozotocin. Rats were randomly divided into two groups:①HBOT group(n=31): inhale oxygen(concentration97%) in animal chamber 1h per day at the pressure of 0.15MPa for 1 to 20 days.②Diabetic control group(DM,n=32): 32 diabetic rats complicated peripheral neuropathy without any treatment.③Normal group(NC,n=20). At the 10th and 20th day of oxygenation, the NCV, latency and wave amplitude of tibial nerve and sural nerve of rats right-behind limbs were measured in the three groups using the electromyograph and the arterial blood was collected from bilateral femoral artery and serum levels of IGF, NGF, NO and MMP-1 were measured. Result: Before treatment,the NCV of diabetic rats was slower than normal rats. At 10 days after HBOT, the NCV of tibial nerve and sural nerve of the right-behind limbs of treatment group was faster significantly than DM group(P0.05), but they were still slower than normal group. The serum levels of NGF and NO increased slightly but without statistical meaning. At 20 days after oxygenation, NCV of the tibial nerve and sural nerve increased significantly than DM group timely and treatment group 10-days before, but there was no significant difference of the NCV between HBOT group and normal group at this time. The abnormal ultrastructure of DM group was improved in treatment group, like the decreasing of axon,and denaturation and incrassation of myelin, and the number of Schwann cell increased significantly than DM group.The levels of NGF,IGF-1 and NO in HBO group were higher than DM group, and its MMP-1 level decreased significantly compared with DM group and baseline.Conclusion:The hyperbaric oxygen therapy improves the peripheral neuropathy in STZ-diabetic rats, its mechanism may be related to induce the synthesis of NGF,IGF-1 and NO, and inhibiting the MMP-1.

Objective To investigate whether hyperbaric oxygen therapy(HBOT) could improve diabetic cardiomyopathy in streptozocin(STZ)-induced diabetic rats.Method Diabetes was induced in 62 SD rats by single intraperitoneal injection of 1.0% STZ.Diabetic cardiomyopathy was showed by electron micrographs.The HBOT group(n=30) was treated with HBO(0.15MPa for 1h) for 20 days and insulin.The diabetic control group(n=32) was treated with insulin only.The normal control group(n=20) undertook abdominal injection of saline.The rats in 2 groups were killed at the 5th,10th and 20th day of the course respectively,their hearts were observed with HE staining and electron microscopy.Results Diabetic cardiomyophy in treatment group was better than that in diabetic control group after 20 days of treatment of HBO.Electron micrographs of ultrastructural observation on the cardiomyocytes showed well organized myofibrils with clear Z lines and normal mitochondria.Conclusions HBOT can improve diabetic cardiomyopathy in STZ-induced diabetic rats.

Aim: To investigate the effects of hyperbaric oxygen therapy (HBOT) on the serum and expression of transforming growth factor-beta 1(TGF-β1) with ultrastructure of kidney in diabetic rats. Methods: 1 The experime nt was conducted at the Animal Ward, Department of Pathology, Shanghai Municipal Fifth People's Hospital and Electron-microscope Room, Shanghai Medical University, Fudan University from October 2002 to March 2003. Ninety male healthy SD rats aged 2 months were selected. Twenty normal rats were retained randomly. Based on 55 mg/kg, other fasting rats were treated with 10 g/L streptozotocin solution with intraperitoneal injection as diabetes model overnight. Among the diabetes rats, there were 63 diabetic nephropathy rats with abnormal ultrastructure after 2-months progress observed with electron microscope. They were assigned randomly into 3 groups: model group (n=32), hyperbaric oxygen treatment group (n=31) and control group (n=20). The 20 rats in the control group were only treated with saline at the same volume with intraperitoneal injection, without intervention. The 32 rats in the model group were treated with regular insulin and deposulin once in the other morning to control glucose from 8 to 13 mmol/ L. The 31 cats in the hyperbaric oxygen treatment group were equally treated with insulin and deposulin to control glucose, entering animal chamber at the pressure of 0.15 MPa, sucking pure oxygen at the concentration of 95% for 1 hour, lasing for 20 days. 2 After being treated with hyperbaric oxygen for 10 and 20 days, respectively, femoral arterial blood and kidney were gained in batch, and then the rats were killed. Caudal vein glucose and body mass were detected with swift glucose apparatus. The femoral arterial blood was gained to detect the level of TGF-β1 of serum in rats of every group. At the same time, the pathological change of kidney was observed using HE staining and electron-microscope, and the TGF-β1 immunostaining in kidney was observed using DAB two-step method. 3 Comparison among groups was performed with t-test. Results: 1 During intervention in batch, 1 rat d ied in the hyperbaric oxygen treatment group, and 2 rats died in the model group. The level of TGF-β1 of serum was detected in 20 rats of control group, 30 rats in hyperbaric oxygen treatment group and 30 rats in model group. After being treated with hyperbaric oxygen for 10 days, 6 rats in the control group, 7 rats in the model group and 7 rats in the hyperbaric oxygen treatment group were killed. After being treated with hyperbaric oxygen for 20 days, 6 rats in the control group, 8 rats in the model group and 8 rats in the hyperbaric oxygen treatment group were killed. Corresponding indexes were detected, respectively. 2 Before treatment, the level of TGF-β1 of serum was significantly higher than that in the control group in diabetes rats (P < 0.05). Pathology mainly showed that glass-like substrate in renal glomerulus was ameliorated, sclerosis and the vessel reduced. Electron microscope observation indicated that vessel loop foot process in glomerular in the model group reduced, combined, arranged disorder, and the interstitial and matrix in the theca cells was deposition and fibrosis. 3 After being treated for 10 days, the level of TGF-β 1 of serum in rats of hyperbaric oxygen treatment group was lower significantly than that in the model group (P < 0.05). The ultrastructure of kidney was improved primarily, but the changes were insignificantly. 4 After being treated for 20 days, the abnormal pathological glomerular in hyperbaric oxygen treatment group lightened, and the ultrastructure improved significantly as compared with the diabetes group, but it was similar to the control group; The level of TGF-β1 of serum was lower significantly than that in the model group (P < 0.01), while the difference was insignificant as compared with control group (P > 0.05). Immunohistochemical method showed that TGF-β1 staining in the interstitial of glomerulus and renal tubule decreased significantly. Conclusion: The hyperbaric oxygen therapy can improve the kidney lesion in diabetes rats, and its mechanism can be related to inhibition of circulating TGF-β1 and expression in kidney.

目的:研究高压氧治疗是否可改善链脲佐菌素(streptozocin,STZ)糖尿病大鼠的周围神经病变并探讨其机制.方法:SD大鼠83只,用STZ制造糖尿病模型成功60 d、肌电图和电镜证实有周围神经病变后,随机分为3组:①高压氧组(n=31):每天接受0.15 MPa、高压氧1 h,连续20 d.②糖尿病对照组(n=32):不做治疗.③正常对照组(n=20):腹腔注射生理盐水的无糖尿病的正常STZ大鼠.分别在疗程5,10,20 d时测定右后肢胫神经、腓神经的传导速度(nerve conduction velocity,NCV)和H反射后处死治疗组及同期对照组大鼠,取坐骨神经进行苏木精-伊红染色病理学观察,同时进行电镜观察.结果:治疗前糖尿病大鼠的胫神经(28.56±6.99)mm/s、腓神经(28.92±7.37)mm/s的NCV明显低于正常组[分别为(48.29±8.04)mm/s,(51.93±8.50)mm/s],而H反射的潜伏期延长,波幅变小.高压氧治疗10d后,治疗组后肢胫神经(45.17±9.80)mm/s和腓神经的传导速度(43.81±7.05)mm/s明显高于同期糖尿病对照组,但低于正常对照组;治疗组H反射的潜伏期(7.27±0.76)ms较糖尿病对照组(7.49±1.26)ms缩短,波幅增大[(1.09±0.39)mV,(0.57±0.30)mV,P＜0.05];病理学变化不明显,但电镜观察显示治疗组的许旺细胞数较糖尿病对照组增多,髓鞘结构有所改善;氧疗20 d后,治疗组后肢胫神经[(46.56±9.72),(36.75±4.29)mm/s]和腓神经[(44.43±11.23),(30.74±6.03)mm/s]的传导速度明显高于糖尿病对照组(P＜0.01),而与正常对照组间无明显差异[分别为(56.6±9.72)mm/s和(45.07±4.08)mm/s,P＞0.05],H反射的潜伏期(7.01±1.14)ms较糖尿病对照组(7.74±0.86)ms进一步缩短(P＜0.05),但波幅变化不明显;病理观察显示此时神经髓鞘和神经纤维结构明显好转;电镜下也观察到许旺细胞增生、有髓神经结构好转、轴突增大等改变.结论:高压氧可改善STZ糖尿病大鼠周围神经病变.

Purpose In order to investigate whether hyperbaric oxygen therapy (HBOT) could improve the peripheral neuropathy in streptozocin (STZ)-induced diabetic rats and its influence on transforming growth factor-β1 (TGF-β1). Methods Diabetic animal model was induced by injection intraperitonally of STZ,and blood glucose were controlled using injection of regular insulin and protamine zine insulin.After 2 months of diabetes onset,the neuropathy was diagnosed through observing the ultrastructure under electron-microscope,and rats were divided randomized into three groups:① Hyperbaric oxygen treatment (HBOT) group(n=31):inhale oxygen (concentration 97%) in animal chamber 1 hour per day at the pressure of 0.15 MPa for 1 to 20 days.② Diabetic model (DM,n=32) group:diabetic rats diagnosed neurepathy without any treatment.③ Normal control (NC,n=20) group:rats were injected normal solution intraperitonally and with normal blood glucose.At the 10 th and 20 th day of oxygenation,the rats in three groups were killed randomized after measuring the nerve conducting velocity(NCV),and the arterial blood were collected from bilateral femoral artery,and the nerve of hind-limb was taken immediately.The glucose levels of nail vein were measured using glucometer before death,and the serum TGF-β1 levels were measured using EIA method.At the same time,the pathological change of nerve tissue was observed using HE staining,and the TGF-β1 immunostaining in peripheral nerve was observed using DAB two-step method.The ultrastructure of them was also observed under electron-microscope. Results Except 1 rat died of anaethesation,30 rats completed the oxygenation in HBOT group.In DM group, excluded 2 died of hypoglycemic coma,data of 30 rats were collected.After 10 days treatment,the serum TGF-β1 levels in HBOT group decreased slightly but significantly than DC group,and they were still higher than NC group.But no obvious neural pathological change was observed in HBOT group,and the improvement of nerve ultrastructure was discovered,like the improvement of myelination and neuraxon and the increasing number of Schwann cells. At 20th day after oxygenation,serum TGF-β1 levels[(121.68±20.01)ng/mL] decreased significantly than that of DM group [(154.71±18.79) ng/mL].There was no significant difference between treatment group and NC group[(125.4±38.38) ng/mL].The improvement of nerve ultrastructure was observed in oxygenation rats but not in DM rats,and the immunostaining of TGF-β1 in nerve axon and compartments beside it was reduced obviously in HBOT group. Conclusions Hyperbaric oxygen therapy improved the peripheral neuropathy in STZ-diabetic rats,and its mechanism may be related to inhibiting the circulation TGF-β1 and its expression in nerve tissue.

目的:检测经高压氧治疗(HBOT)的有糖尿病性心肌病变的STZ(链脲佐菌素)大鼠血浆细胞因子水平,探讨高压氧治疗糖尿病性心肌病变的作用机理.方法:STZ糖尿病大鼠造模成功3个月、电镜证实有糖尿病性心肌病变后,随机分为三组:(1)HBOT组(n=30):每天接受0.15MPa、HBOT 1h,连续20d.(2)糖尿病对照组(n=32):不做治疗.(3)正常对照组(n=20):腹腔注射生理盐水的无糖尿病的正常大鼠.分别在疗程5d、10d、20d后处死三组大鼠,测定三组大鼠血清NGF、IGF-1、TGF-β、NO和MMP-1水平.结果:HBO治疗10d后,HBOT组心肌病变明显好于同期糖尿病对照组,低于正常对照组;血清NGF、NO水平稍有增高,但与对照组间无显著差异.HBOT 20d后,血清NGF和NO水平显著高于糖尿病对照组(均P＜0.01),治疗组血IGF-1水平显著高于DM组(P=0.00084),但仍低于正常对照组(P=0.00153);血清MMP-1、TGF-β水平较糖尿病组明显降低(P＜0.05).结论:HBOT改善STZ大鼠糖尿病性心肌病变的机理可能与促进NGF、IGF-1合成和血清NO增加、抑制MMP-1和TGF-β有关.