The action of topical basic fibroblast growth factor in facial nerve regeneration.
OBJECTIVE
To analyze the influence of the topical use of basic fibroblast growth factor (bFGF) in the regeneration of the facial nerve in rats.


METHODS
Experimental study.


METHODS
Twenty-eight Wistar adult male rats underwent complete section of the facial nerve trunk, followed by end-to-end anastomosis with epineural sutures. An osmotic minipump equipped with a delivery catheter was implanted subcutaneously near the neural anastomosis. During the subsequent 14 days, 14 animals received a solution containing 25 microg/ml of bFGF, 250 UI/ml of sodium heparin, and 1,000 microg/ml of human albumin diluted in Ringer lactate, and 14 animals received a control solution of the same components without bFGF. To evaluate facial nerve regeneration, the number of myelinated fibers evident on histologic sections was counted on the 14th (7 experimental and 8 control animals) and the 28th days (7 experimental and 6 control animals) after surgery, and the facial movements of vibrissae and the blink reflex were evaluated on alternate days until the 28th day.


RESULTS
On histologic evaluation, the number of myelinated fibers was similar between groups on the 14th day and greater in the group that received bFGF on the 28th day. Behavioral evaluation showed that the animals of the bFGF group presented better functional results between the 6th and 16th days for the blink test and the 14th to the 16th days for vibrissae movements.


CONCLUSIONS
This study showed that the regeneration of the facial nerve occurred earlier and resulted in significantly more myelinated nerve fibers in the animals that received topical bFGF.
Toledo
Ronaldo N
RN
Department of Otorhinolaryngology-Head and Neck Surgery, Federal University of São Paulo, Rua dos Otonis 700, São Paulo, Brazil. rntoledo@uol.com.br
Borin
Andrei
A
Cruz
Oswaldo L M
OL
Ho
Paulo L
PL
Testa
José R G
JR
Fukuda
Yotaka
Y
D000279:Administration, Cutaneous; D000818:Animals; D001767:Blinking / Q000187:drug effects; D002452:Cell Count; D020220:Facial Nerve Injuries / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D016222:Fibroblast Growth Factor 2 / Q000008:administration & dosage*; D008297:Male; D009413:Nerve Fibers, Myelinated / Q000187:drug effects* / Q000473:pathology; D009416:Nerve Regeneration / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D020127:Recovery of Function / Q000187:drug effects*; D018709:Statistics, Nonparametric; D014738:Vibrissae / Q000187:drug effects
D016222:Fibroblast Growth Factor 2