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 develop a technique that can directly demonstrate collateral sprouting of intact nerve fibers at endtoside neurorrhaphy site. Methods Five Wistar adult rats were used in this study. The common peroneal nerves at one side were sectioned at the level of knee joint, and their distal ends were sutured to the tibial nerves after removal of a 1 mm-diameter window in the epineurium. Three months after the operation, the nerve segments at neurorrhaphy site and the normal tibial nerves at the contralateral site were harvested. The specimens were fixed in 10% formaldehyde and postfixed in 1% osmium tetroxide, thenmacerated in glycerol. Single fiber was teased out in pure glycerol under an operative microscope, then transferred to a slide and observed under light microscope. The nerve segments at neurorrhaphy site and distal peroneal nerves were alsoharvested for histological evaluation. Results At the neurorrhaphy site, small nerve fibers sprouted from a donor nerve fiber near node’s of Ranvier. While such phenomena were not found in normal tibial nerve. From the longitudinal sectionof neurorrhaphy site, bundles of nerve fibers ranged from tibial nerve to peroneal nerve were observed. Lots of regenerative nerve fibers emerged in distal peroneal nerve. Conclusion The phenomena of collateral sprouting at end-to-side neurorrhaphy site can be demonstrated directly by nerve fiber micro-tease technique.
Objective To reconstruct the blood supply of hepatic artery of therecipient rat by a modified arterial “sleeve” anastomoses. Methods SD-SD and SD-Wistar rats liver transplantation were performed in 30 and 50 cases, respectively. The donor splenic artery, left gastric artery, right gastric artery and gastroduodenal artery were ligated, meanwhile the proper hepatic arteries were reserved. The celiac trunk of donors and the stump of right kidney artery of recipient were anastomosed by using 8-0 suture with “sleeve” technique. Results Themean time of artery anastomoses was 4.00±1.31 min.The rate of success was 96.3％. The longest survival time in the model SD-SD(29 survived) was more than 2months. In SD-Wistar(48 survived), acute rejectiion was observed 3-5 days after operation andthe mean survival time of rat was 9 d. Conclusion The modifiedarterial “sleeve” anastomoses is an effective method to reconstruct blood supply of hepatic artery of rat recipient in rat liver transplantation.
Objective To investigate the effect ofestrogen on osteoarthritis in female rats.Methods Forty female rats were divided into four groups. In group Ⅰ, the rats were not given any treatment as a control. Ingroups Ⅱ, Ⅲ and Ⅳ, the rats received fixing left knee joint on extension position. Meanwhile, therats received ovariectomy in group Ⅲ; ovariectomy and diethylstilbestrol treatment in group Ⅳ, respectively. After 4 weeks, histological observation and serum BGP examination were done.Results In groups Ⅱ, Ⅲ andⅣ, the levels of serum BGP were 3.50±0.39, 5.72±0.64 and 3.95±0.44, respectively. The pathologic grades of cartilage and synovium were 10.83±4.35 and 4.21±2.03; 15.32±3.42 and 7.62±3.42; and 12.65±2.73 and 5.46±1.23, respectively. Conclusion Estrogen may play an important role in delaying the development of osteoarthritis.