[Effect of ventricle injection of Nogo-A antibody on neuronal regeneration following hypoxic-ischemic brain damage in the neonatal rat].
OBJECTIVE
Nogo-A antibody IN-1 can neutralize Nogo-A, a neurite growth inhibitory protein, promoting axonal regeneration following lesions of the central nervous system (CNS) in adult rats. This study aimed to examine the effect of ventricle injection of Nogo-A antibody on neuronal regeneration in neonatal rats following hypoxic-ischemic brain damage (HIBD).


METHODS
A model of neonatal HIBD was prepared by the ligation of the left common carotid artery, followed by 8% hypoxia exposure. Forty HIBD rats were randomly given a ventricle injection of 10 microL Nogo-A antibody IN-1 (IN-1 group) or 10 microL artificial cerebrospinal fluid (artificial CSF group) (n=20 each). Another 20 neonatal rats were sham-operated, without hypoxia-ischemia, and were used as the controls. The levels of Nogo-A and GAP-43 protein in the brain were measured by immunohistochemistry.


RESULTS
The number of immunohistory positive cells of Nogo-A in the brain in the IN-1 group (28.61+/-1.70) was obviously less than that in the artificial CSF (39.52 +/-1.40) and the sham-operated groups (32.78 +/- 1.87) (both P < 0.01). There were significant differences in the Nogo-A protein expression between the artificial CSF and the sham-operated groups (P < 0.01). The GAP-43 protein expression in the IN-1 group (31.14 +/- 1.88) was noticeably higher than that in the artificial CSF group (27.73 +/- 1.43 ) (P < 0.01). Both the IN-1 and the artificial CSF groups showed lower GAP-43 protein levels than the sham-operated groups (33.64 +/- 1.24) (both P < 0.01).


CONCLUSIONS
Nogo-A antibody can reduce the expression of Nogo-A protein in the brain and thus promote neuronal regeneration in neonatal rats following HIBD. An increased GAP-43 protein expression in the brain after Nogo-A antibody administration shows an enhanced neuronal regeneration in the neonatal rats following HIBD.
Zhou
Xiao-Guang
XG
Department of Neonatology, Second Hospital of Guangzhou Medical College, Guangzhou 510260, China. gzzhouxg@163.net
Liu
Ren-Hong
RH
Xiong
Ai-Hua
AH
D000818:Animals; D000831:Animals, Newborn; D000906:Antibodies / Q000008:administration & dosage*; D001923:Brain Chemistry; D005260:Female; D019922:GAP-43 Protein / Q000032:analysis; D020925:Hypoxia-Ischemia, Brain / Q000378:metabolism / Q000503:physiopathology / Q000628:therapy*; D007150:Immunohistochemistry; D007276:Injections, Intraventricular; D008297:Male; D009185:Myelin Proteins / Q000032:analysis / Q000037:antagonists & inhibitors* / Q000276:immunology; D009416:Nerve Regeneration; D000070798:Nogo Proteins; D051381:Rats; D017207:Rats, Sprague-Dawley
D000906:Antibodies; D019922:GAP-43 Protein; D009185:Myelin Proteins; D000070798:Nogo Proteins; C000603197:Rtn4 protein, rat