PMID- 24251983
OWN - NLM
STAT- MEDLINE
DCOM- 20140929
LR  - 20240410
IS  - 1469-7580 (Electronic)
IS  - 0021-8782 (Print)
IS  - 0021-8782 (Linking)
VI  - 224
IP  - 2
DP  - 2014 Feb
TI  - Osteoblast-osteocyte transformation. A SEM densitometric analysis of endosteal 
      apposition in rabbit femur.
PG  - 132-41
LID - 10.1111/joa.12138 [doi]
AB  - Transformation of osteoblasts into osteocytes is marked by changes in volume and 
      cell shape. The reduction of volume and the entrapment process are correlated 
      with the synthesis activity of the cell which decreases consequently. This 
      transformation process has been extensively investigated by transmission electron 
      microscopy (TEM) but no data have yet been published regarding 
      osteoblast-osteocyte dynamic histomorphometry. Scanning electron microscope (SEM) 
      densitometric analysis was carried out to determine the osteoblast and open 
      osteocyte lacunae density in corresponding areas of a rabbit femur endosteal 
      surface. The lining cell density was 4900.1 +/- 30.03 n mm(-2), the one of open 
      osteocyte lacunae 72.89 +/- 22.55 n mm(-2). This corresponds to an index of 
      entrapment of one cell every 67.23 osteoblasts (approximated by defect). The 
      entrapment sequence begins with flattening of the osteoblast and spreading of 
      equatorial processes. At first these are covered by the new apposed matrix and 
      then also the whole cellular body of the osteocyte undergoing entrapment. The 
      dorsal aspect of the cell membrane suggests that closure of the osteocyte lacuna 
      may be partially carried out by the same osteoblast-osteocyte which developed a 
      dorsal secretory territory. A significant proportion of the endosteal surface was 
      analysed by SEM, without observing any evidence of osteoblast mitotic figures. 
      This indicates that recruitment of the pool of osteogenic cells in cortical bone 
      lamellar systems occurs prior to the entrapment process. No further additions 
      occurred once osteoblasts were positioned on the bone surface and began lamellar 
      apposition. The number of active osteoblasts on the endosteal surface exceeded 
      that of the cells which become incorporated as osteocytes (whose number was 
      indicated by the number of osteocyte lacunae). Therefore such a balance must be 
      equilibrated by the osteoblasts' transformation in resting lining cells or by 
      apoptosis. The current work characterised osteoblast shape changes throughout the 
      entrapment process, allowing approximate calculation of an osteoblast entrapment 
      index in the rabbit endosteal cortex.
CI  - (c) 2013 Anatomical Society.
FAU - Pazzaglia, Ugo E
AU  - Pazzaglia UE
AD  - Department of Medical and Surgical Specialties, Radiological Sciences and Public 
      Health, University of Brescia, Brescia, Italy.
FAU - Congiu, Terenzio
AU  - Congiu T
FAU - Sibilia, Valeria
AU  - Sibilia V
FAU - Quacci, Daniela
AU  - Quacci D
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20131120
PL  - England
TA  - J Anat
JT  - Journal of anatomy
JID - 0137162
SB  - IM
MH  - Animals
MH  - Cell Growth Processes
MH  - Densitometry
MH  - Femur/*cytology/growth & development
MH  - Male
MH  - Osteoblasts/*ultrastructure
MH  - Osteocytes/*ultrastructure
MH  - Rabbits
MH  - Reference Values
PMC - PMC3969057
OTO - NOTNLM
OT  - osteoblast
OT  - osteocyte
OT  - osteocyte entrapment
EDAT- 2013/11/21 06:00
MHDA- 2014/09/30 06:00
PMCR- 2016/02/01
CRDT- 2013/11/21 06:00
PHST- 2013/10/14 00:00 [accepted]
PHST- 2013/11/21 06:00 [entrez]
PHST- 2013/11/21 06:00 [pubmed]
PHST- 2014/09/30 06:00 [medline]
PHST- 2016/02/01 00:00 [pmc-release]
AID - 10.1111/joa.12138 [doi]
PST - ppublish
SO  - J Anat. 2014 Feb;224(2):132-41. doi: 10.1111/joa.12138. Epub 2013 Nov 20.