PMID- 10831935
OWN - NLM
STAT- MEDLINE
DCOM- 20000630
LR  - 20190905
IS  - 8756-3282 (Print)
IS  - 1873-2763 (Linking)
VI  - 26
IP  - 6
DP  - 2000 Jun
TI  - Expression of neurotrophins and their receptors (TRK) during fracture healing.
PG  - 625-33
AB  - To clarify the roles of neurotrophins and their receptors in bone formation, 
      expression of neurotrophins and their receptors (TRK) in a model of mouse 
      fracture healing was investigated. A total of 120 male ICR mice were studied. The 
      right eighth rib of 70 mice was fractured. For sham operation as a control, the 
      right eighth rib of 50 mice was similarly exposed but not fractured. Localization 
      of TRKA, TRKB, and TRKC in a rectangular region of the rib together with 
      surrounding soft tissues was investigated by immunostaining. Localizations of 
      nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and 
      neurotrophin-3 (NT-3) at the fracture callus were also investigated by 
      immunostaining, and their mitochondrial RNA (mRNA) expressions were investigated 
      by reverse transcriptase-polymerase chain reaction (RT-PCR). As a result, we 
      observed two types of neurotrophin receptors in the bone forming area: 
      immunostaining by anti-TRKA was observed in almost all bone forming cells, and 
      staining with anti-TRKC was observed in osteoblast-like cells and hypertrophic 
      chondrocytes, but no staining was observed with anti-TRKB. On the other hand, 
      localization of NGF was observed in almost all bone forming cells, localization 
      of BDNF was observed in osteoblast-like cells, and localization of NT-3 was 
      observed in osteoblast-like cells and hypertrophic chondrocytes at the fracture 
      callus. Expression levels of the mRNA of three neurotrophins in the fractured rib 
      were increased during the process of healing, especially those of NGF and NT-3, 
      which peaked at 2 days after the fracture. The level of BDNF mRNA increased 
      gradually over 8 days. These findings show that neurotrophins and their receptors 
      were expressed in bone forming cells, and suggest that they are involved in the 
      regulation of bone formation as an autocrine and paracrine factor in vivo.
FAU - Asaumi, K
AU  - Asaumi K
AD  - Department of Biochemistry and Molecular Dentistry, Okayama University Dental 
      School, Okayama, Japan.
FAU - Nakanishi, T
AU  - Nakanishi T
FAU - Asahara, H
AU  - Asahara H
FAU - Inoue, H
AU  - Inoue H
FAU - Takigawa, M
AU  - Takigawa M
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Bone
JT  - Bone
JID - 8504048
RN  - 0 (DNA Primers)
RN  - 0 (Nerve Growth Factors)
RN  - 0 (RNA, Messenger)
RN  - 0 (Receptors, Nerve Growth Factor)
SB  - IM
MH  - Animals
MH  - Base Sequence
MH  - DNA Primers
MH  - Fracture Healing/*genetics
MH  - Male
MH  - Mice
MH  - Mice, Inbred C57BL
MH  - Nerve Growth Factors/*genetics
MH  - RNA, Messenger/genetics
MH  - Receptors, Nerve Growth Factor/*genetics
MH  - Reverse Transcriptase Polymerase Chain Reaction
EDAT- 2000/06/01 09:00
MHDA- 2000/07/08 11:00
CRDT- 2000/06/01 09:00
PHST- 2000/06/01 09:00 [pubmed]
PHST- 2000/07/08 11:00 [medline]
PHST- 2000/06/01 09:00 [entrez]
AID - S8756-3282(00)00281-7 [pii]
AID - 10.1016/s8756-3282(00)00281-7 [doi]
PST - ppublish
SO  - Bone. 2000 Jun;26(6):625-33. doi: 10.1016/s8756-3282(00)00281-7.