Local application of anti-NGF blocks the collateral sprouting in rats following chronic constriction injury of the sciatic nerve.
Systemic administration of anti-nerve growth factor (NGF) antibodies can block nociceptive fiber sprouting into denervated adult rat skin. However, the effect of local application of anti-NGF on collateral sprouting in rats caused by chronic constriction injury (CCI) has not been well studied. We investigated the influence of local anti-NGF on collateral sprouting caused by CCI of the rat's sciatic nerve. Using a dye-labeled plasma extravasation technique, we can easily evaluate the extent of collateral sprouting by the clearly defined blue coloration area. Our results showed that local application of anti-NGF either in a high or low dose significantly prevented the spread of collateral sprouting from the saphenous nerve into the sciatic innervation territory. In contrast, distilled water did not show a significant block of the saphenous nerve collateral sprouting. Our study suggests that collateral sprouting is dependent on the local availability of NGF by the nearby intact cutaneous nerve fibers.
Ro
L S
LS
Department of Neurology, Chang Gung Memorial Hospital, Taipei, Taiwan, ROC.
Chen
S T
ST
Tang
L M
LM
Chang
H S
HS
D000818:Animals; D008297:Male; D009414:Nerve Growth Factors / Q000494:pharmacology*; D010147:Pain Measurement; D051381:Rats; D017207:Rats, Sprague-Dawley; D012584:Sciatic Nerve / Q000502:physiology*; D012867:Skin / Q000187:drug effects*; D013997:Time Factors
D009414:Nerve Growth Factors