Pre-degenerated peripheral nerve extracts applied to the proximal stump of transected sciatic nerve enhance both regeneration and autotomic behavior in rats.
BACKGROUND
Peripheral nerve regeneration after traumatic injury and standard repair with a nerve autograft is often incomplete and results in neuropathic pain. Peripheral nerve extracts applied to the proximal nerve stump by means of autologous, dead-ended connective tissue chambers (deCTC) are known to accelerate the rate of axon regeneration. This study tested if such extracts would influence autotomy, which is a behavioral measure of neuropathic pain in animal models.


METHODS
The study was performed on Wistar rats. DeCTCs, filled with postmicrosomal fraction obtained from 7-day-predegenerated nerves (7D group) or fibrin (F group), were implanted into transected sciatic nerve. In the control group (C), sciatic nerve was transected and its distal part was removed. The self-mutilation behavior in rats was assessed daily for seven weeks after sciatic nerve transection. The onset as well as intensity of autotomy was measured. The progress of regeneration was assessed under light microscopy and histochemistry.


RESULTS
The earliest onset and greatest severity of autotomy were found in the 7D group. Regeneration progress was also highest in this group. In the F group, we found weaker regeneration and less autotomy. The control group showed no regeneration, but more autotomy than the F group.


CONCLUSIONS
Intensified autotomy may be the price paid for enhanced peripheral nerve regeneration after application of growth-promoting substances.
Lewin-Kowalik
Joanna
J
Department of Physiology, Silesian Medical University, Katowice, Poland. fzjkatpl@infomed.slam.katowice.pl
Marcol
Wiesław
W
Larysz-Brysz
Magdalena
M
Wolwender
Katarzyna
K
Pietrucha-Dutczak
Marita
M
Górka
Dariusz
D
D000818:Animals; D001522:Behavior, Animal; D003714:Denervation; D005337:Fibrin / Q000378:metabolism; D008297:Male; D009416:Nerve Regeneration / Q000502:physiology*; D010146:Pain / Q000503:physiopathology; D010525:Peripheral Nerves / Q000737:chemistry* / Q000166:cytology / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012584:Sciatic Nerve / Q000166:cytology / Q000293:injuries / Q000502:physiology*; D012652:Self Mutilation; D014020:Tissue Extracts / Q000737:chemistry* / Q000378:metabolism; D019737:Transplants
D014020:Tissue Extracts; D005337:Fibrin