[The effects of an NGF isolated and purified from venom of Naja naja atra on GAP-43 in spinal cord dorsal horn of cats subjected to partial rhizotomy].
OBJECTIVE
To investigate the effects of a nerve growth factor (NGF) isolated and purified from the venom of Naja naja atra on GAP-43 in spinal cord dorsal horn of cats subjected to partial rhizotomy.


METHODS
A total of 45 adult male cats were subjected to unilateral rhizotomy of L1-L5 and L7-S2 dorsal roots, with the intact L6 as spared dorsal root. Then the cats were equally divided into the NGF low-dosage group (1 microg/kg), NGF high-dosage group (2 microg/kg), normal saline control group, and were allowed to survive 3 days, 6 days, 12 days respectively. Immunohistochemical technique was used to detect GAP-43 of L6 segments of spinal cord.


RESULTS
After the operation, GAP-43 positive products were mainly distributed in the nerve terminals of spinal cord I, II, III. Expression of GAP-43 positive products was detected at 3 days and 6 days after the operation; the nerve terminals of regeneration increased and reached the highest level on the 12th day; there was significant difference between the control group and the treatment groups; the regeneration level of the NGF-high-dosage group was significantly (P < 0.01) higher than that of the other groups.


CONCLUSIONS
NGF can effectively induce the synthesis of neuronal structural protein in the process of recovery of spinal cord damage and enhance the spared root's collateral sprouting; the density of positive nerve terminals is related with NGF dosage.
Chen
Li-Hua
LH
Department of Medical Cosmesis, School of Clinical Medicine, Dali College, Dali 671000, China.
Wang
Yan
Y
Li
Guang-Yue
GY
Li
Hai-Yan
HY
D000818:Animals; D002415:Cats; D004546:Elapid Venoms / Q000737:chemistry*; D019922:GAP-43 Protein / Q000096:biosynthesis* / Q000235:genetics; D008297:Male; D009414:Nerve Growth Factors / Q000302:isolation & purification / Q000494:pharmacology*; D009473:Neuronal Plasticity; D020671:Posterior Horn Cells / Q000378:metabolism*; D011897:Random Allocation; D013116:Spinal Cord / Q000378:metabolism*
D004546:Elapid Venoms; D019922:GAP-43 Protein; D009414:Nerve Growth Factors