Objective To explore effects of several immunosuppressants on cytokine expressions after repair for a sciatic nerve injury in a rat model. Methods The sciatic nerves of 42 rats were cut and suturedend to end. After operation, the rats were divided into 6 groups. Group A(n=9) was served as a control with no medicines given. Group B (n=9) was given methylprednisolone 20 mg/(kg·d) for 2 days. Groups C(n=9) and D(n=3) were given FK506 1 mg/(kg·d) for 2 weeks and 4 weeks respectively, and were given the same doses of methylprednisolone as Group B. Groups E and F were given CsA 2 mg/(kg·d) for 2 weeks and 4 weeks respectively, and were given the same doses of methylprednisolone as Group B. The sciaticnerves were sampled at 1, 2 and 4 weeks postoperatively. And immuneohistochemistry stainings of interleukin 1β(IL-1β)， tumor necrosis factor α(TNF-α), interferon γ(IFN-γ) and macrophage migration inhibitory factor(MIF) were performed. The staining results were compared and analyzed. Results The expression peaks of IL-1β and IFN-γ were found at the 1st week postoperatively in Group A. Then, the expression decreased rapidly at the 2nd week and disappeared at the 4th week. As for TNF-α and MIF, they were only found to have a low expression until the 1st week in Group A. In groups C-F, the expression peaks of IL-1β, TNF-α and IFN-γ were found at the 2nd week, while the expression peak of MIF was still at the 1st week, and the expression of all the cytokines extended to the 4th week. The expressions of these cytokines in Group B were just between the expression levels of Group A and Groups C-F. Conclusion Immunosuppressants can delay the expression peaks and significantly extend the expression time of IL-1β, TNF-α, IFN-γ and MIF after repair for a sciatic nerve injury in a rat model.
OBJECTIVE: To study the effect of subcutaneous implant of peripheral nerve allograft on sciatic nerve regeneration in rats. METHODS: Out of 30 male Wistar rats, 6 were donors and 24 were divided randomly into 2 groups. In experimental group (group A, n = 12), a 15 mm segment of sciatic nerve harvested from donors was separately inserted into subcutaneous compartment on the right thigh; two weeks later, the segment of sciatic nerve in subcutaneous compartment was removed and transplanted into a 10 mm sciatic nerve defect of left, which was made immediately. In the control group (group B, n = 12), a 10 mm sciatic nerve defect was made and immediately repaired in situ on the left thigh. The regeneration of sciatic nerve was examined histologically (after 2, 4, 8, and 14 weeks) and electrophysiologically (after 14 weeks of operation). RESULTS: After 2 weeks of operation, the inflammatory reaction was a little ber in group A than in group B. After 4 weeks, the intensity of the inflammatory reaction was similar between two groups; some collagen fibers proliferated. After 8 weeks, the inflammatory reaction ended and the collagen fibers proliferated obviously. After 14 weeks of operation, the structure of epineurium was in integrity and there was no obvious difference in perineurium and endonurium between two groups. A large number of myelinated nerve fibers and a small number of unmyelinated nerve fibers regenerated. The structure of myelin sheath was in integrity. The number and size of regenerated axon had no significant difference between two groups(P gt; 0.05). The conduction velocity, the peak value and the latent period of motor nerve were no significant difference between two groups (P gt; 0.05). CONCLUSION: The allograft of sciatic nerve inserted into subcutaneous compartment can promote nerve regeneration.
Objective To study the effects of the periosteum，synovium andcartilage tissues on the gene expressions of proteoglycan, collagen Ⅱ, andnuclear factor kappa B (NF-κB) and to investigate the different effects of these tissues on cartilage regeneration. Methods In 20 New Zealand white rabbits, 20 cartilage explants were taken from the knee joints in each rabbit, the sizeof which was 4 mm×4 mm×4 mm. All the cartilages were divided into the following 4 groups and cultured for 7 days: Group A, with 5 pieces (2 mm×2 mm) of the synovium of theknee joints in each dish; Group B, with 5 pieces (2 mm×2 mm) of the periosteum ineach dish; Group C, with 5 pieces (2 mm×2 mm×2 mm) of the cartilage in each dish; and Group D, with no addition of other tissues (control group). RNA was extracted from the cells of the cartilage explants (4 mm×4 mm×4 mm) in all the dishes. Thegene expressions of proteoglycan, collagen Ⅱ and NF-κB were defected by a reversetranscription-polymerase chain reaction (RT-PCR).Results In group A, the gene expression of proteoglycan was significantly decreased. The relative density of this gene expression had a significant difference when compared with that in group D (1.09±0.21 vs. 1.25±0.25, Plt;0.05); the gene expressions of collagen Ⅱ and NF-κB were also decreased, but they had no significant differences when compared with those in group D (Pgt;0.05). In groupB, the gene expressions of proteoglycan, collagen Ⅱ, and NF-κB were significantly increased. The relative densities of these gene expressions were 1.60±0.26, 1.57±0.24, and 4.20±2.22, respectively, which had significant differences when compared with those in group D (Plt;0.05). In group C, the relative density of the gene expression of collagen Ⅱ was 1.43±0.28, which had a significant difference when compared with that in group D (Plt;0.05), but therelative densities of the gene expressions of proteoglycan and NF-κB had no significant differences when compared with those in group D (Pgt;0.05). Conclusion The results indicate that the periosteum can up-regulate the gene expressions of proteoglycan, collagen Ⅱ and NF-κB. The NF-κB is likely to be an important nuclear transcription factor related to cartilage regeneration. The results also suggest that the periosteum maybe better in facilitating the cartilage repair and regeneration in clinical practice.
On the basis of laboratory research of the reinnervation of poralyysed musele by implanting muscle bundies with neurovascular pedicle ( NVMBI),this method was applied clinically to trcat paralysed musele on extremities and trunks with quite satisfactory result.Detail description of preoperative exammation,operation design,surgical procedure and potoperative management were presented。the mechanism and reason of the good result were dscussed. The anatomical characteristics of the NVMBI we...
Objective To study an effect of the peripheral nerve allograft with subcutaneous preservation at different times on the sciatic nerve regenerationin rats. Methods Fifty-five Wistar rats were used in this experiment, which were randomly divided into the following 5 groups: the experimental groups (Groups A, B, C, 10 rats), the control group (Group D, 10 rats), and the donorgroup (Group E, 15 rats). In the experimental groups, a 15-mm segment of the sciatic nerve harvested from the donors was separately inserted into the subcutaneous compartment on the left thigh after the 1week (Group A), 2-week (Group B), and 3week (Group C) preservation; the segment of the sciatic nerve in the subcutaneous compartment was removed and transplanted into a 10-mm defect of theright sciatic nerve, which was made immediately. In Group D, a 10-mm sciatic nerve defect was made and immediately repaired in situ on the right thigh. The function of the sciatic nerve was evaluated by the sciatic functional index (SFI) at 2, 4, 6, 8, 10 and 12 weeks after operation. The histological and electrophysiological examinations were performed at 12 weeks after operation. Results After operation, SFI decreased gradually at 12 weeks afteroperation, SFI inGroups A and D was at the minimal level and had a significant difference compared with that in Groups B and C (Plt;0.05).There was no significant difference between Group A and Group D. A large number of the myelinated nerve fibers and a small number of the unmyelinated nerve fibers were regenerated in Groups A and D. The number and the structure of the regenerated nerve were similar to the normal ones. The number and the size of the regenerated axon had a significant difference compared with those in Groups B and C (Plt;0.05). There was no significant difference between Group A and Group D. The conduction velocity and the latent period of the motor nerve had significant differences between Groups A and D and Groups B and C (Plt;0.05), and there was no significant difference betweenGroupA and Group D. Conclusion The nerve allograft with a 1-weeksubcutaneous preservation can promote nerve regeneration better.
Objective To discuss peripheral nerve regeneration under immunosuppression. Methods Current research trends about relationship between peripheral nerve injury and immunoreaction, the experimental result of nerve regeneration after using various immunosuppressors, and the clinical findings after human allogenous hand transplantation were extensively reviewed. Results Peripheral nerve regeneration was accelerated under immunosuppression. Conclusion Peripheral nerve injury may induce immunoreaction, which inhibit nerve regeneration and function recovery.
OBJECTIVE: To review the role of thyroid hormone in the peripheral nerve regeneration. METHODS: The recent literatures of experimental study and clinical application on the role of thyroid hormone in nerve regeneration were reviewed. The researches on expression, isoform and changes of thyroid hormones in rat sciatic nerve in normal or injury were summarized. The effect of thyroid hormone on local rat sciatic nerve was studied, too. RESULTS: Nuclear thyroid hormone receptors expressed in numerous nuclei of sciatic nerve during a limited period of development extending from the third week of embryonic life to the end of the second postnatal week and after injury of adult sciatic nerve. A single and local administration of thyroid hormone at the level of the transected sciatic nerve produced a lasting effect on peripheral nerve regeneration. CONCLUSION: The beneficial effects of thyroid hormones upon injured peripheral nerve may have considerable therapeutic potential.
ObjectiveTo develop and modify a rat model of partial liver transplantation with hepatic arterialization and to investigate the postoperative histopathologic changes of the grafts. MethodsModified twocuff technique was applied to establish a rat model of partial liver transplantation, and the donor’s celiac artery was anastomosed with the recipient’s right renal artery. The biopsy of the grafts was performed on the day 1,2,4 and 7 after transplantation. Results85.4% of the recipients had survived for one week.Nuclear mitoses were seen on the postoperative day 2 by microscopy, while on the day 4 they were found occasionally. Two nucleus cells were seen on the day 4 and 7. Conclusion The stability of the model is improved by modifying the technique. Liver acupuncture biopsy is a simple, safe and feasible way to be applied in the research of postoperative problems of liver transplantation. Reconstruction of hepatic artery is possible to enhance the regeneration of liver grafts.
This article reported the implantation of the greater auricular nerve into the cervicoshoulder skin flap in rabbits. The progress following implantation of the nerve was continuously observed. According to the time elapsed from the nervesbeing implanted, the experimental animals were divided into 4 groups, 4 animalsin each group, in the order of 1, 2, 4 and 6 months groups, respectively, and the normal skin and the cervicoshoulder skin flaps without nerve implantation were used as control. The electron microscope was the method used to observed theprogress. The results showed that in the 2nd month the unmyelinated fibers first appeared, then the myelinated in the 4th month. The caliber of the axons, the thickness of the myelin sheath and the ratio of MF/UF increased with time. In the 4th month, the number of the regenerating nerve fibers (unmyelinated fibers predominant) had achieved the highest level and significantly exceeded that of thenormal skin. But at the 6 months. the MF/UF ratio was still for lower than normal.
Objective To investigate the velvet antler polypeptide (VAP) on sciatic nerve regeneration in rats through local administration and VAP-PLGA compound membrane. Methods The 3, 15 mg/g of VAP-PLGA compound membranewere prepared by compounding VAP and PLGA, respectively. Seventy-two Wistar rats, male or female, aged 3-6 months and weighing (250 ± 50) g, were selected to make the model of sciatic nerve section. Then, all rats were randomized into 4 groups (n=18): group A in which nothing was given after anatomosis, group B in which 1 mL of VAP at the concentration of 10 mg/L was injected into the gastrocnemius muscle medial for every other day, group C in which 3 mg/g of VAP-PLGA compound membrane was given to the nerve anastomotic stoma and group D in which 15 mg/g of VAP-PLGA compound membrane was given to the nerve anastomotic stoma. The sciatic adhesion degree observation, electrophysiological examination, immunohistochemical staining and hemi-quantity calculation and horseradish peroxidase (HRP) retrograde tracing were conducted 2, 4 and 6 weeks after operation, respectively. Results All rats survived to the end of the experiment, without foot ulcer or neuroma. Severer nervous adherence was observed in group A, mild adherence in group B, and no adherence in groups C and D 2, 4 and 6 weeks after operation, respectively. The recovery rate of the evoked potential of triceps surae in groups B, C and D was better than that in group A (P lt; 0.01), group D was superior to groups B and C (P lt; 0.05) at each time point. No significant difference between group B and group C (P gt; 0.05) 2, 4 weeks after operation was detected, but group C was superior to group B (P lt; 0.05) 6 weeksafter operation. For the regenerative fiber axon and the expression of myelin sheath TGF-β1 and IGF antigen, the staining intensity in groups B, C and D was higher than that in group A at each time point (P lt; 0.05), and there were significant differences between group D and groups B and C 6 weeks after operation (P lt; 0.05), but no difference between groups B and C (P gt; 0.05). The HRP retrograde tracing showed that the myelinated nerve fiber stained by HRP gradually increased as time passed by and myelinated nerve fiber stained by HRP in groups B, C and D was much more than that in group A, and group D was superior to the other groups. No significant difference between group B and group C was detected. Conclusion To apply VAP through either local administration or VAP-PLGA compound membrane around the attached site of nerve anastomosis is capable of promoting nerve regeneration, which has an obvious dose-effect relationship with the dose of VAP. Meanwhile, VAP-PLGA compound membrane can prevent the nerve adhesion.