The relationship between sural nerve morphometric findings and measures of peripheral nerve function in mild diabetic neuropathy.

The morphological findings in sural nerve biopsy specimens from 15 diabetic patients with mild neuropathy were compared with control biopsies from eight non-neuropathic, non-diabetic subjects, and correlations were sought with electrophysiological studies and quantitative sensory tests for vibration, thermal, and current perception thresholds. Myelinated fibre density was reduced compared with control biopsies (4042 +/- 2090 (+/- SD) vs 6800 +/- 1100 mm-2; p less than 0.01). A strong correlation existed between myelinated fibre density and sural sensory conduction velocity (r = 0.84, p less than 0.001), sural action potential amplitude (r = 0.74, p less than 0.001), peroneal motor conduction velocity (r = 0.58, p less than 0.02), and median sensory amplitude (r = 0.64, p less than 0.01) but there was no correlation between myelinated fibre density and any quantitative sensory test. We conclude that conventional electrophysiological tests in the lower limb are reliable surrogate measures for structural abnormalities in early diabetic neuropathy.     

A multicentre trial of the aldose-reductase inhibitor,tolrestat, in patients with symptomatic diabetic neuropathy

Summary The effects of the aldose-reductase inhibitor, tolrestat, on chronic symptomatic diabetic sensorimotor neuropathy were studied during a placebo-controlled, randomised, 52-week multicentre trial. Of the four tolrestat doses investigated, only the highest dose group, 200 mg once daily, showed subjective and objective benefit over baseline and placebo, and further analyses are confined to this group (n=112) and placebo (n=107). Painful and paraesthetic symptoms were analysed separately: improvement in paraesthetic symptoms were seen at one year (p=0.04), though painful symptoms improved on both placebo and active therapies. Significant improvement in both tibial and peroneal motor nerve conduction velocities were seen at 52 weeks. Tolrestat 200 mg once daily was significantly better than placebo in producing concordant improvements in both motor nerve conduction velocities and paraesthetic symptom scores at 24 weeks (p=0.01), 42 weeks (p=0.01) and 52 weeks (p=0.02). Long-term benefit [condordant improvement at 24 weeks maintained until 52 weeks] was seen in 28% of treated patients compared to 5% on placebo (p=0.001). It is concluded that some sustained improvement in symptomatic diabetic neuropathy may be obtained following aldose-reductase inhibition with tolrestat 200 mg once daily.Prepared by the authors for the North American tolrestat in neuropathy research group.     

糖尿病痛性周围神经病的临床及电生理特点分析

目的探讨糖尿病痛性周围神经病（PDPN）的临床和电生理特点。方法严格入选32例PDPN患者,病程〉1年,疼痛视觉模拟评分〉4,未伴有其他内科系统合并症,进行视觉模拟评分（VAS）并记录疼痛性质。电生理检测包括：常规神经传导速度（NCV）、定量感觉检测（温度觉）（QST-t）。结果PDPN往往有客观的感觉异常,但神经系统体征不典型,NCV检测可正常,而QST—t可有异常表现,本组NCV检测13例正常,其中11例QST-t异常;本组NCV异常率为59．4％,QST异常率为87．5％,QST＋NCV异常率为93．7％。VAS与QST的上下肢热痛觉（HP）呈正相关（t=0．595、P=0．009;t=0．784、P=0．004）,与胫神经的感觉神经传导速度（SCV）呈负相关（t=-0．554;P=0．032）;与其它电生理各项参数不相关,与空腹血糖、糖化血红蛋白、病程及疼痛病程不相关。结论PDPN以小纤维受累为主,QST可为早期PDPN提供客观的临床依据;疼痛程度与C类纤维及下肢胫神经感觉纤维病变有一定的相关性。     

Pattern of myelinated fibre loss in the sural nerve in neuropathy related to Type 1 (insulin-dependent) diabetes

Summary Sural nerve biopsies were obtained from 17 diabetic patients with neuropathy. All patients except three had both a symmetric distal sensory and autonomic polyneuropathy related to Type 1 (insulin-dependent) diabetes mellitus; 3 patients had a purely sensory polyneuropathy. Mean age was 34.5 years (range 18–53 years). The biopsies were compared with specimens from an age-matched control series. Myelinated fibre loss in the diabetic nerves was found to be nonuniform. Although patchy fibre loss has been considered to favour a vascular basis, an identical pattern of nonuniform loss was observed in a series of sural nerve biopsies from patients with Type I hereditary motor and sensory neuropathy, a subgroup within the spectrum of peroneal muscular atrophy, mainly of autosomal dominant inheritance, and a condition in which a vascular causation can be discounted. Possible reasons for nonuniform fibre loss other than vascular disease are discussed.     

The influence of isolated small nerve fibre dysfunction on microvascular control in patients with diabetes mellitus.

AIM: The aim of the study was to investigate the influence of isolated small nerve fibre dysfunction on microvascular skin blood flow and transcutaneous oxygen tension in patients with diabetes mellitus. METHODS: Small nerve fibre dysfunction was assessed by the measurement of thermal and pain perception thresholds. Patients with evidence of large fibre disturbances as evaluated by means of vibration perception threshold were excluded from the study. Microvascular blood flow was investigated with laser-Doppler-fluxmetry (LDF) following stimulation with acetylcholine and mild thermal injury. RESULTS: Diabetic patients with small nerve fibre injury showed a significantly reduced increase in the laser-Doppler-flux signal following the application of acetylcholine compared with patients without neuropathy or healthy control subjects (2.8 arbitrary units (AU) (1.3-5.5) vs. 7.2 AU (4.1-25.5); P = 0.007 and vs. 8.5 AU (3.0-17.0), P = 0.02, respectively). The increase in LDF following thermal injury was also diminished in patients with small nerve fibre dysfunction compared with patients without neuropathy or the control group (29.8 AU (17.2-46.5) vs. 51.2 AU (29.5-93.5); P = 0.02 and vs. 54.6 AU (39.7-97.7); P = 0.004, respectively). In addition, they showed a significantly reduced transcutaneous oxygen tension compared with the other groups (42.9 mmHg (41.6-55.5) vs. 56.1 mmHg (49.2-60.8); P = 0.04 and vs. 59.0 mmHg (54.6-80.3), P = 0.03, respectively). CONCLUSIONS: Our study confirms an association between small nerve fibre injury and skin microvascular dysfunction. It further underlines the concept of neurovascular disturbances in the pathogenesis of neurotrophic foot ulceration. Diabet. Med. 18, 489-494 (2001)     

A new minimally invasive technique to show nerve ischaemia in diabetic neuropathy

Aims/hypothesis. Experimental studies have shown that abnormalities of nerve microcirculation are important factors in the pathogenesis of diabetic neuropathy but there have been few clinical studies. We have applied microlightguide spectrophotometry to measure intravascular oxygen saturation (HbO₂%) and blood flow in human sural nerve. Methods. We studied ten patients with mild-moderate sensory motor diabetic neuropathy, nine patients without neuropathy and nine control subjects. We took 300 measurements of oxygen saturation under direct visual control through a 1.9 mm rigid endoscope over three regions of the nerve. Spectrophotometric measurements of nerve fluorescence were taken after an intravenous injection of sodium fluorescein and the rate of increase in nerve fluorescence (rise time) was used as an indicator of nerve blood flow. Results. Nerve oxygen saturation was reduced in patients with neuropathy compared with control subjects (67.1 ± 2.2 % vs 76.7 ± 2.1 %, p = 0.006). Fluorescein rise time was prolonged in patients with neuropathy compared with the control group (48.5 ± 7.0 s vs 14.0 ± 3.1 s, p = 0.001) suggesting impaired nerve blood flow. There was a correlation between rise time, nerve oxygen saturation, glycaemic control and sural nerve sensory conduction velocity (p < 0.01). Conclusion/interpretation. The combination of microlight-guide spectrophotometry and micro-endoscopy provides a valuable minimally invasive technique for clinical investigation of nerve microcirculation. We have shown reduced nerve oxygenation and impaired blood flow in diabetic neuropathy and these findings strongly support a central role of microvascular disease in the pathogenesis of diabetic neuropathy. [Diabetologia (1999) 42: 737–742] Received: 8 October 1998 and in revised form: 7 January 1999     

Clinical observations and experiments in diabetic neuropathy

Summary Diabetic neuropathies form a group of diverse conditions, which can be distinguished between those which recover (acute painful neuropathies, radiculopathies, mononeuropathies) and those which progress (sensory and autonomic neuropathies). These two main groups can be distinguished in several ways: sensory and autonomic neuropathies are classic diabetic complications progressing gradually in patients with long-standing diabetes who often have other specific complications, while the reversible neuropathies do not have these features. The latter are characterised by their occurrence at any stage of diabetes, often at diagnosis, they may be precipitated on starting insulin treatment, and they are more common in men; they can occur at any age, though more often in older patients, and are unrelated to other diabetic complications. The two groups of neuropathies also show differences in nerve structural abnormalities and with regard to distinctive blood flow responses. The underlying mechanisms responsible for these very different forms of neuropathy remain speculative, but evidence for an immunological basis for the development of severe symptomatic autonomic neuropathy is presented.This review was presented as the Camillo Golgi lecture at the EASD meeting in Copenhagen, September 1990     

加巴喷丁治疗糖尿病性神经痛的研究进展

糖尿病性神经痛是神经病理性疼痛的一个主要类型,患病人数多,治疗困难.加巴喷丁是一种新型的抗癫痫药物,目前被广泛应用十治疗糖尿病性神经痛,其镇痛机制尚未完全明确,对电压门控钙通道α2δ-1亚单位的调节作用可能是其主要作用机制.加巴喷丁治疗糖尿病神经性疼痛效果明确,不良反应轻微,是治疗糖尿病性神经痛较为理想的药物.     

Small fibre neuropathy: role in the diagnosis of diabetic sensorimotor polyneuropathy

Small fibres constitute 70–90% of peripheral nerve fibres and regulate several key functions such as tissue blood flow, temperature and pain perception as well as sweating, all of which are highly relevant to the clinical presentation and adverse outcomes associated with foot ulcerations in patients with diabetes. Recent studies demonstrated significant abnormalities in the small fibres in subjects with impaired glucose tolerance and diabetes, despite normal electrophysiology, suggesting that the earliest nerve fibre damage is to the small fibres. Unfortunately, guidelines and consensus statements focus on large fibres and continue to advocate electrophysiology as a diagnostic modality and as a primary end point for the assessment of therapeutic benefit. (In part, this reflects the difficulties in quantifying small fibre dysfunction and damage.) We have therefore critically assessed currently available techniques that measure small fibre dysfunction in diabetic neuropathy, using quantitative sensory and sudomotor testing. We have assessed the role of identifying structural damage by quantifying intraepidermal nerve fibre density in skin biopsies and corneal nerve morphology using corneal confocal microscopy. Finally, we propose a definition for diabetic neuropathy that incorporates small fibre damage. Copyright © 2011 John Wiley & Sons, Ltd.     

Effect of cilostazol on experimental diabetic neuropathy in the rat

Summary Two proposed mechanisms of diabetic neuropathy are microvascular ischaemia and a reduction in Na,K-ATPase activity. We evaluated the effect of cilostazol, a drug that is both a potent phosphodiesterase inhibitor that normalizes nerve Na,K-AT-Pase and a vasodilator, on nerve blood flow (NBF) to determine whether it would improve experimental diabetic neuropathy. We examined whether epineurally applied cilostazol acted as a vasodilator on the peripheral nerve of normal and diabetic rats, and whether feeding the rats a cilostazol-supplemented diet could improve diabetic neuropathy. Cilostazol increased nerve blood flow (NBF) in a dose-dependent fashion with an EC₅₀ of 10^–5.74 mol/l. Cilostazol also normalized NBF in experimental diabetic neuropathy with a 10^–4 mol/l local application on the sciatic nerve. In diabetic neuropathy, a cilostazol-supplemented diet improved both NBF and nerve conduction in a dose- and time-dependent fashion. Potential mechanisms of action of cilostazol on the nerve include its effect on NBF, Na, K-ATPase, and restoration of the thromboxane:prostacyclin ratio. Cilostazol may have potential in the treatment of diabetic neuropathy.Abbreviations EDN Experimental diabetic neuropathy - NBF nerve blood flow - STZ streptozotocin - NRC control rats receiving normal diet - NRH control rats receiving a high (0.1%) cilostazol diet - CSH STZ rats receiving high (0.1%) cilostazol diet - CSL STZ rats receiving low (0.03%) cilostazol diet - CV conduction velocity     

The skin hyperaemic response to local injection of substance P and capsaicin in diabetes mellitus.

Recent studies have demonstrated impaired skin hyperaemia to local injury in diabetes mellitus. In order to gain insight into the mechanisms of impaired hyperaemia, dose-response curves to intradermal substance P (25, 50, 100 pmol) and capsaicin (1.0, 2.5, 5.0 nmol) were examined before and after histamine blockade with chlorpheniramine, in 6 patients with uncomplicated Type 1 diabetes and 9 matched control subjects. Skin hyperaemia was measured indirectly as the peak laser Doppler flow in proximity to the area of hyperaemia. The response to the three doses of substance P was significantly lower in diabetic patients (0.37 +/- 0.12 (+/- SD), 0.51 +/- 0.12, 0.67 +/- 0.09 V) than in control subjects (0.57 +/- 0.15, 0.70 +/- 0.19, 0.84 +/- 0.21 V; p less than 0.01). In contrast there was no significant difference in skin hyperaemia to capsaicin between diabetic patients (0.41 +/- 0.07, 0.50 +/- 0.09, 0.59 +/- 0.09 V) and control subjects (0.41 +/- 0.06, 0.52 +/- 0.08, 0.63 +/- 0.07 V). Following chlorpheniramine, the response to capsaicin remained unaltered (0.39 +/- 0.07, 0.51 +/- 0.05, 0.60 +/- 0.07 in diabetic patients and 0.43 +/- 0.08, 0.50 +/- 0.10, 0.63 +/- 0.07 V in control subjects), but there was a significant reduction in hyperaemia to substance P in both patients (20.4 +/- 12.3% reduction, p less than 0.05) and control subjects (20.6 +/- 14.1% reduction, p less than 0.05). It is suggested that impaired skin hyperaemia may represent decreased vascular reactivity to locally released substance P from peripheral nerve fibres.     

神经生长因子改善实验性糖尿病大鼠的感觉神经功能

观察了链脲佐菌素糖尿病大鼠成模两个月后，投用神经生长因子（ＮＧＦ）对糖尿病神经病变的影响。结果显示，外源性注射ＮＧＦ１个月后，摇尾试验（一种鼠对热毒刺激的反应）热痛阈值明显恢复，坐骨神经的感觉神经传导速度有所改善。初步显示了ＮＧＦ对糖尿病感觉神经病变的治疗作用。     

The problem of autonomic neuropathy in diabetic pregnancy

The hazards of pregnancy for both the mother and the fetus in diabetic women with severe retinopathy and nephropathy are well reported. We wish to highlight a poorly recognized problem in the obstetric management of the diabetic mother, that of pregnancy in a patient with autonomic neuropathy. Two such cases are reported where the presence of autonomic neuropathy severely jeopardized the health of the mother, with the loss of the fetus in one, due to occurrence of severe and intractable vomiting. The presence of moderate to severe symptomatic diabetic autonomic neuropathy, particularly with evidence of gastroparesis, may be a relative contraindication to pregnancy.     

Exercise-induced conduction velocity increment: a marker of impaired peripheral nerve blood flow in diabetic neuropathy

Summary Severe microvascular disease exists at the stage of clinical diabetic neuropathy. A non-invasive test that will identify those diabetic subjects who will eventually develop neuropathy is essential for early intervention. Sural sensory conduction velocity was recorded (x 3) in 12 non-neuropathic diabetic subjects, 15 diabetic subjects with established neuropathy and 16 age-matched normal control subjects, before and after exercise to 80% age/sex predicted maximum heart rate. Fixed sural electrodes were used. Subcutaneous temperature was recorded by a needle thermocouple placed near the sural nerve. Sural sensory conduction velocity increased significantly after exercise in normal subjects (p<0.01, mean increase 5.07 m/s) and non-neuropathic diabetic subjects (p<0.02, mean increase 3.99 m/s) but not in neuropathic subjects (mean increase 0.99 m/s). Subcutaneous temperature rose significantly in normal subjects (p<0.01, mean increase 2.07°C) and non-neuropathic diabetic subjects (p<0.001, mean increase 2.52 °C) but not in neuropathic subjects (mean increase 0.15 °C). However, sural sensory conduction velocity increased by 1.2 m · s^–1. °C^–1 following direct warming of the limb in six neuropathic subjects which was comparable to that of normal and non-neuropathic subjects (1.49 and 1.48 m · s^–1. °C^–1). The impairment of exercise conduction increment in diabetic neuropathy suggests impaired nerve blood flow in diabetic neuropathy.     

Morphometry of endoneurial capillaries in diabetic sensory and autonomic neuropathy

Summary Nerve biopsies were obtained from 27 patients with diabetic neuropathy. All had a symmetric distal sensory and autonomic neuropathy or a purely sensory neuropathy. Mean age was 39.8 years (range 23–57 years). Two patients had Type 2 (non-insulin-dependent) diabetes mellitus and the remainder Type 1 (insulin-dependent) diabetes. Morphometric observations on endoneurial capillaries were compared with results from organ donor control cases and from patients with type 1 hereditary motor and sensory neuropathy. The area of the lumen of the capillaries did not differ between the three groups. The area occupied by the capillary endothelial cells in transverse section and the number of endothelial cell nuclei were increased both in the patients with diabetic neuropathy and hereditary motor and sensory neuropathy, as was the thickness of the surrounding basal laminal zone. Closure of endoneurial capillaries in diabetic neuropathy, reported in another study, was not confirmed. Capillary density and nearest-neighbour distances were similar in the diabetic and organ donor control cases. Capillary density was reduced in the patients with hereditary motor and sensory neuropathy, this being related to increased fascicular area consequent upon the presence of hypertrophic changes. The presence of thickening of the pericapillary basal laminal zone and endothelial cell hyperplasia both in diabetic and hereditary motor and sensory neuropathy, the latter being a neuropathy in which a vascular basis can be discounted, makes it difficult to use such changes as an argument favouring a vascular cause for diabetic neuropathy. There were differences in the basal laminal zone between the diabetic and hereditary motor and sensory neuropathy cases suggesting that the reduplicated basal lamina was more persistent in the diabetic patients.     

Autonomic nerve antibodies and autonomic nerve function in type 1 and type 2 diabetic patients

Complement-fixing adrenal medulla (CF-ADM), sympathetic ganglion (CF-SG), and vagal (CF-V) nerve antibodies were determined in diabetic patients. Among 74 patients with Type 1 diabetes, CF-ADM was detected in 7 (10%) cases, CF-SG in 14 (19%) cases, and CF-V in 8 (11%) cases. Among 38 patients with Type 2 diabetes, CF-ADM was detected in 5 (13%) cases, CF-SG in 4 (11%) cases, and CF-V in 6 (16%) cases. There were associations between autonomic nerve antibodies and autonomic nerve function. CF-ADM and/or CF-SG were significantly (P less than 0.002) less prevalent in Type 1 diabetic patients with autonomic neuropathy than in those without [5/44 (11%) vs. 14/30 (47%)] and, in agreement with this, the brake index, a sign of parasympathetic and sympathetic autonomic nerve function, was significantly (P less than 0.005) higher (more normal) in these patients (-0.56 +/- 0.13 vs. -1.04 +/- 0.12). In Type 2 diabetic patients, the E/I ratio, an index of parasympathetic nerve function, was significantly (P less than 0.03) lower (more abnormal) in those with CF-V than in those without (-1.81 +/- 0.17 vs. -1.20 +/- 0.11). In conclusion, the frequency of sympathetic nerve antibodies was decreased in Type 1 diabetic patients with autonomic neuropathy, while in Type 2 diabetic patients parasympathetic nerve antibodies were related to severe parasympathetic neuropathy.     

Prolonged preservation of nerve function in diabetic neuropathy in mice by herpes simplex virus-mediated gene transfer

Aims/hypothesis The aim of this study was to determine whether prolonged expression of neurotrophin-3 (NT-3) in mice, achieved by herpes simplex virus (HSV)-mediated gene transfer with gene expression under the control of an HSV latency promoter, can provide protection against the progression of diabetic neuropathy over a 6 month period. Materials and methods Mice with diabetes induced by streptozotocin were inoculated s.c. into both hind feet with a non-replicating HSV vector containing the coding sequence for NT-3 under the control of the HSV latency-associated promoter 2 (LAP2) elements or with a control vector. Nerve function was evaluated by electrophysiological and behavioural measures over the course of 6 months after the onset of diabetes. Results Animals inoculated with the NT-3-expressing vector, but not animals inoculated with control vector, showed preservation of sensory and motor nerve amplitude and conduction velocity measured electrophysiologically, small fibre sensory function assessed by withdrawal from heat, autonomic function measured by pilocarpine-induced sweating, skin innervation assessed by protein gene product 9.5 staining of axons, and density of calcitonin gene-related peptide terminals in the spinal cord measured by immunohistochemistry 5.5 months after vector inoculation. Conclusions/interpretation These results indicate that the continuous production of NT-3 by LAP2-driven expression of the transgene from an HSV vector over a 6 month period protects against progression of diabetic neuropathy in mice, and provide a proof-of-principle demonstration for the development of a novel therapy for preventing the progression of diabetic neuropathy.     

The potential of transdermal nitric oxide treatment for diabetic peripheral neuropathy and diabetic foot ulcers

The Center for Disease Control (CDC) estimates that 29 million Americans have diabetes, and 70% of diabetic patients develop diabetic peripheral neuropathy [1,2]. Up to 27% of the direct medical cost of diabetes may be attributed to DPN [3]. A 2013 article from the American Diabetes Association reported a $176 billion direct medical cost of diabetes in 2012 [4]. DPN patients often suffer from shooting and burning pain in their distal limbs and a severe loss of sensation. Diabetic foot ulcers, infections, and amputations may follow. Currently available treatments: tricyclic antidepressants, anticonvulsants such as gabapentin and pregabalin, serotonin and norepinephrine reuptake inhibitor, duloxetine, topical 5% lidocaine (applied to the most painful area) can manage painful symptoms but do not address the underlying pathologies of DPN and diabetic wound ulcers. A combination of pain-reducing medications can provide relief when individual medications fail, and opioids such as tramadol and oxycodone may be administered with these medications to reduce pain [5]. Due to the prevalence of diabetes, DPN, and diabetic foot ulcers, and because of the lack of available effective treatments to directly address the pathology contributing to these conditions, novel treatments are being sought. Our hypothesis is that a deficiency of nitric oxide synthase in diabetic patients leads to a lack of vascularization of the peripheral nerves, which causes DPN; and this could be treated with vasodilators such as nitric oxide. In this paper, the mechanisms of DPN are reviewed and analyzed to elucidate the potential of a transdermal nitric oxide application for the treatment of DPN and diabetic wound ulcers by increasing vasodilation.     

Near normoglycaemia improved nerve conduction and vibration sensation in diabetic neuropathy

Summary Twelve C-peptide deficient Type 1 (insulin-dependent) diabetic patients with abnormal peripheral nerve function were randomly assigned to continuation of conventional insulin therapy (CIT) or to continuous subcutaneous insulin infusion (CSII). There were no statistically significant differences at entry to the study between the two treatment groups in nerve function assessed by neurologic disability score, computer assisted sensation examination and measurements of amplitudes, distal latencies, F-wave latencies and somatosensory evoked potential latencies over the spine and conduction velocities of motor and sensory fibers of ulnar, median, peroneal, tibial, plantar and sural nerves. In addition, mean plasma glucose from 24 h profiles (12.5 vs 10.6 mmol/l, respectively) and HbA₁ (11.0 vs 11.6%, respectively) did not differ significantly between the two treatment groups at entry. Despite improved glycaemia from CSII in 5 patients (one dropped out of the study after 2 months) contrasted to CIT in 6 patients (5.3 vs 9.9 mmol/l, respectively, p=0.002) and HbA1 (8.5 vs 10.7%, respectively, p=0.002), there were no significant differences in measurements of peripheral nerve function after 4 months. After 8 months of improved glycaemia (4.4 vs 10.2 mmol/l, p=0.004) and improved HbA₁, (8.3 vs 10.5%, p=0.002), nerve conduction (p=0.03) and vibratory sensation threshold (p=0.002) were significantly better in patients treated with CSII than those who received CIT. The improvements in nerve function, although small, provide further evidence that some clinical endpoints of neuropathy are favorably influenced by improved control of glycaemia.     

周围神经减压术对糖尿病神经卡压大鼠细胞因子表达的影响

目的 探讨周围神经减压术对DPN大鼠模型脊髓背根神经节中细胞因子表达的影响.方法 50只SD大鼠以STZ诱导糖尿病模型.2周后,筛选造模成功的大鼠32只随机分为糖尿病对照组（DM组,n=8）、糖尿病神经卡压组（DPN组,n=12）及糖尿病神经卡压＋外周神经减压组（DPND组,n=12）.DM组不予任何干预,DPN及DPND组制作坐骨神经卡压模型.6周后,DPND组予神经减压术,DPN组予假神经减压手术.于神经卡压前后及减压手术前后不同时间（术前、术后2周、术后6周）分别以Von Frey单丝测定各组机械痛阈.术后6周,观察各组脊髓背根神经节病理,并通过酶联免疫法测定背根神经节中TNF-α、环氧酶2（COX-2）、VEGF及神经生长相关蛋白-43（GAP-43）的表达.结果 DPND组行神经减压术6周后机械痛阈较减压手术前及DPN组改善（P＜0.05）;脊髓背根神经节炎性反应及水肿现象轻于DPN组,且背根神经节中TNF-α及COX-2表达较DPN组降低,其中COX-2改变差异有统计学意义（P＜0.05）.DPND组VEGF及GAP-43的表达较DPN组有增高趋势,但差异无统计学意义. 结论 神经减压术可改善周围神经卡压造成的糖尿病大鼠机械痛阈升高现象,这可能与其调节脊髓背根神经节中相关细胞因子的表达有关.