The effects of decompression and exogenous NGF on compressed cerebral cortex.
Using a rat epidural bead implantation model, we found that compression alone could reduce the overall and individual layer thicknesses of cerebral cortex with no apparent cell death. The dendritic lengths and spine densities of layer II/III and V pyramidal neurons started to decrease within 3 days of compression. Decompression for 14 days resulted in near complete to partial recovery of the cortical thickness and of the dendritic lengths of layer II/III and V pyramidal neurons, depending on the duration of the preceding compression. The recoverability was better following short (3-day) than long (1- or 3-month) periods of compression. The loss of dendritic spines nevertheless persisted. An intraventricular infusion of NGF was performed after decompressing the lesions following 3 days of cortical compression, and this increased the recovery of the spines but not the dendritic length of the cortical pyramidal neurons, nor did it alter the recovery of the cortical thickness. NGF also promoted the increase of the dendritic spines, but not the dendritic length of the cortical pyramidal neurons of normal animals. In short, the data show that a few days of compression alone can cause permanent cortical damage. Exogenous NGF, if applied topically, may restore the dendritic spine density of cortical neurons subjected to compression.
Chen
Jeng-Rung
JR
Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei, Taiwan.
Wang
Yueh-Jan
YJ
Tseng
Guo-Fang
GF
D000818:Animals; D001930:Brain Injuries / Q000188:drug therapy* / Q000503:physiopathology / Q000601:surgery*; D048430:Cell Shape / Q000502:physiology; D002540:Cerebral Cortex / Q000187:drug effects* / Q000473:pathology / Q000601:surgery*; D019299:Decompression, Surgical; D049229:Dendritic Spines / Q000473:pathology; D004195:Disease Models, Animal; D004824:Epidural Space / Q000473:pathology / Q000503:physiopathology; D005260:Female; D009410:Nerve Degeneration / Q000473:pathology / Q000503:physiopathology / Q000628:therapy; D020932:Nerve Growth Factor / Q000494:pharmacology* / Q000627:therapeutic use; D011312:Pressure / Q000009:adverse effects; D017966:Pyramidal Cells / Q000187:drug effects / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D020127:Recovery of Function / Q000187:drug effects / Q000502:physiology; D013997:Time Factors
D020932:Nerve Growth Factor