title: Neuronal differentiation of PC12 cells induced by sciatic nerve and optic nerve conditioned medium.
abstract: BACKGROUND
  Previous work has shown that optic nerve and sciatic nerve conditional medium had neurotrophic activity on neurons. In order to find if the optic nerve conditioned media (CM) had a similar activity to make PC12 cells differentiate as sciatic nerve CM did, we explored the neurotrophic activity in optic nerve CM in the same in vitro system and compared the neurotrophin expression levels in optic and sciatic nerves under both conditions.
  
  
  METHODS
  PC12 cells were used to examine the effects of neurotrophins secreted by the sciatic nerve and optic nerve. RT-PCR and real-time QPCR showed that the sciatic nerve and optic nerve produced a range of neurotrophins including nerve growth factor (NGF), brain derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3).
  
  
  RESULTS
  The effects of sciatic nerve and optic nerve CM on neurite outgrowth were tested against a range of neurotrophins, and they had different neuritogenic activities. Only NGF and sciatic nerve CM had obvious neuritogenic activities, although the concentration of NGF in the sciatic nerve CM was very low.
  
  
  CONCLUSIONS
  Our experiment showed that sciatic nerve CM had a higher neurotrophic activity on PC12 cells than optic nerve CM. These results suggested that peripheral nervous system (PNS) and central nervous system (CNS) had different expression levels of neurotrophin, which may in part explain the lack of ability to regenerate the CNS.
authors.affiliation: Department of Orthopedics and Traumatology, Peking University People's Hospital, Beijing 100044, China.
authors.forename: Chan
authors.initials: C
authors.lastname: DU
authors.forename: De-mei
authors.initials: DM
authors.lastname: Yang
authors.forename: Pei-xun
authors.initials: PX
authors.lastname: Zhang
authors.forename: Lei
authors.initials: L
authors.lastname: Deng
authors.forename: Bao-guo
authors.initials: BG
authors.lastname: Jiang
mesh_terms: D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects*; D017077:Culture Media, Conditioned / Q000378:metabolism / Q000494:pharmacology*; D020932:Nerve Growth Factor / Q000235:genetics / Q000494:pharmacology; D020933:Neurotrophin 3 / Q000235:genetics / Q000494:pharmacology; D009900:Optic Nerve / Q000378:metabolism*; D016716:PC12 Cells / Q000166:cytology* / Q000187:drug effects*; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012584:Sciatic Nerve / Q000378:metabolism*
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D017077:Culture Media, Conditioned; D020933:Neurotrophin 3; D020932:Nerve Growth Factor