OBJECTIVETo assess the effect of cyclosporine A (CsA) loaded in chitosan conduit on bridging the sciatic nerve defects in a rat model.

METHODSA 10 mm sciatic nerve defect was bridged using a chitosan conduit filled with 10 μl carrier-drug dilution (10 μg/L CsA). In control group, the conduit was filled with the same volume of carrier dilution alone. The regene-rated fibers were studied 4, 8 and 12 weeks after surgery.

RESULTSThe functional study confirmed faster recovery of the regenerated axons in treatment group than control group (P<0.05). There was statistically significant difference of the gastrocnemius muscle weight ratios between treatment and control groups (P<0.05). Morphometric indices of regenerated fibers showed that the number and diameter of the myelinated fibers in CsA-treated animals were significantly higher than those in control group. In immunohistochemistry, the location of reactions to S-100 in CsA group was clearly more positive than control group.

CONCLUSIONCsA loaded in a chitosan conduit results in improvement of functional recovery and quantitative morphometric indices of sciatic nerve. It is easily available without any complications compared with its systemic administration.

Animals ; Chitosan ; Cyclosporine ; administration & dosage ; pharmacology ; Immunohistochemistry ; Nerve Regeneration ; drug effects ; Rats ; Sciatic Nerve ; chemistry ; injuries

OBJECTIVETo evaluate the local effect of vascular endothelial growth factor (VEGF) on transected sciatic nerve regeneration.

METHODSSixty male white Wistar rats were divided into four experimental groups randomly (n equal to 15). In transected group the left sciatic nerve was transected and the stump was fixed to adjacent muscle. In treatment group the defect was bridged using a silicone graft filled with 10 microlitre VEGF. In silicone group the graft was filled with phosphate-buffered saline. In sham-operated group the sciatic nerve was exposed and manipulated. Each group was subdivided into three subgroups with five animals in each and nerve fibers were studied 4, 8 and 12 weeks after operation.

RESULTSBehavioral test, functional study of sciatic nerve, gastrocnemius muscle mass and morphometric indices confirmed a faster recovery of regenerated axons in VEGF group than in silicone group (P less than 0.05). In immunohistochemical assessment, reactions to S-100 in VEGF group were more positive than that in silicone group.

CONCLUSIONLocal administration of VEGF will improve functional recovery and morphometric indices of sciatic nerve.

Administration, Topical ; Animals ; Nerve Regeneration ; drug effects ; Rats ; Rats, Wistar ; Sciatic Nerve ; surgery ; Vascular Endothelial Growth Factor A

OBJECTIVEPresent study aimed at further comprehensive functional, histomorphometrical and immunohistochemical assessment of peripheral nerve regeneration using rat sciatic nerve transection model.

METHODSThe 10-mm rat sciatic nerve gap was created in rats. In control group nerve stumps were sutured to adjacent muscle and in treatment group the gap was bridged using an inside-out vein graft. In sham-operated group the nerve was manipulated and left intact. All animals underwent walking track analysis test 4, 8, and 12 weeks after surgery. Subsequently, muscle mass measurement was performed to assess reenervation, histological examination to observe the sciatic nerve regeneration morphologically and immunohistochemistry to detect Schwann cells using anti S-100. Results were analyzed using a factorial ANOVA with two between-subjects factors. Bonferroni test for pairwise comparisons was used to examine the effect of treatments.

RESULTSFunctional analysis of myelinated nerve fibers showed that nerve function improved significantly in the time course in treatment group. However, quantitative morphometrical analysis of myelinated nerve fibers showed that there was no significant difference between 8 and 12 weeks in treatment group. Muscle weight ratio was bigger and weight loss of the gastrocnemius muscle was ameliorated by inside-out vein grafting. The position of positive immunohistochemical reactions further implied that regenerated axons and Schwann cell-like cells existed after vein grafting was performed, and was accompanied by the process of myelination and structural recovery of regenerated nerves.

CONCLUSIONFunctional analysis of peripheral nerve repair is far more reliable than quantitative morphometrical analysis.

Animals ; Immunohistochemistry ; Male ; Nerve Regeneration ; Rats ; Recovery of Function ; S100 Proteins ; analysis ; Sciatic Nerve ; physiology ; surgery ; Veins ; transplantation

OBJECTIVETo assess local effect of celecoxib on nerve regeneration in a rat sciatic nerve transection model.

METHODSForty-five male healthy white Wistar rats were randomly divided into three experimental groups (n equal to 15 for each): sham-operation (SHAM), control (SIL) and celecoxib treated (SIL/CLX) groups. In SHAM group after anesthesia left sciatic nerve was exposed and after homeostasis muscle was sutured. In SIL group the left sciatic nerve was exposed in the same way and transected proximal to tibioperoneal bifurcation leaving a 10 mm gap. Proximal and distal stumps were each inserted into a silicone tube and filled with 10 microlitre phosphate buffered solution. In SIL/CLX group defect was bridged using a silicone tube filled with 10 microlitre celecoxib (0.1 g/L).

RESULTSFunctional study and gastrocnemius muscle mass confirmed faster and better recovery of regenerated axons in SIL/CLX than in SIL group (P less than 0.05). Morphometric indices of regenerated fibers showed number and diameter of the myelinated fibers in SIL/CLX were significantly greater than those in control group. In immunohistochemistry, location of reactions to S-100 in SIL/CLX was clearly more positive than that in SIL group.

CONCLUSIONResponse to local treatment of celecoxib demonstrates that it influences and improves functional recovery of peripheral nerve regeneration.

Animals ; Celecoxib ; Cyclooxygenase 2 Inhibitors ; pharmacology ; Male ; Nerve Regeneration ; drug effects ; Peripheral Nerves ; drug effects ; surgery ; Pyrazoles ; pharmacokinetics ; Random Allocation ; Rats ; Rats, Wistar ; Sciatic Nerve ; drug effects ; Silicones ; Sulfonamides ; pharmacokinetics