Identification of adequate vehicles to carry nerve regeneration inducers using tubulisation.
BACKGROUND
Axonal regeneration depends on many factors, such as the type of injury and repair, age, distance from the cell body and distance of the denervated muscle, loss of surrounding tissue and the type of injured nerve. Experimental models use tubulisation with a silicone tube to research regenerative factors and substances to induce regeneration. Agarose, collagen and DMEM (Dulbecco's modified Eagle's medium) can be used as vehicles. In this study, we compared the ability of these vehicles to induce rat sciatic nerve regeneration with the intent of finding the least active or inert substance. The experiment used 47 female Wistar rats, which were divided into four experimental groups (agarose 4%, agarose 0.4%, collagen, DMEM) and one normal control group. The right sciatic nerve was exposed, and an incision was made that created a 10 mm gap between the distal and proximal stumps. A silicone tube was grafted onto each stump, and the tubes were filled with the respective media. After 70 days, the sciatic nerve was removed. We evaluated the formation of a regeneration cable, nerve fibre growth, and the functional viability of the regenerated fibres.


RESULTS
Comparison among the three vehicles showed that 0.4% agarose gels had almost no effect on provoking the regeneration of peripheral nerves and that 4% agarose gels completely prevented fibre growth. The others substances were associated with profuse nerve fibre growth.


CONCLUSIONS
In the appropriate concentration, agarose gel may be an important vehicle for testing factors that induce regeneration without interfering with nerve growth.
Department of Neurosciences, School of Medicine of Ribeirão Preto, University of São Paulo, Brazil.
Adriana Helena
AH
do Nascimento-Elias
Bruno César
BC
Fresnesdas
Maria Cristina Lopes
MC
Schiavoni
Natália Fernanda Gaspar
NF
de Almeida
Ana Paula
AP
Santos
Jean
J
de Oliveira Ramos
Wilson Marques
WM
Junior
Amilton Antunes
AA
Barreira
D000818:Animals; D001369:Axons / Q000187:drug effects / Q000473:pathology; D003094:Collagen / Q000627:therapeutic use*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005260:Female; D009413:Nerve Fibers, Myelinated / Q000187:drug effects; D009416:Nerve Regeneration / Q000187:drug effects* / Q000502:physiology; D019736:Prostheses and Implants; D051381:Rats; D017208:Rats, Wistar; D012584:Sciatic Nerve / Q000187:drug effects / Q000473:pathology; D020426:Sciatic Neuropathy / Q000188:drug therapy / Q000473:pathology / Q000601:surgery*; D012685:Sepharose / Q000627:therapeutic use*; D012828:Silicones / Q000627:therapeutic use; D013997:Time Factors
D012828:Silicones; D003094:Collagen; D012685:Sepharose