TY - JOUR
T1 - Determinants of spatial polarity in the growth plate
AU - Abad, Veronica
AU - Uyeda, Jennifer A.
AU - Temple, H. Thomas
AU - De Luca, Francesco
AU - Baron, Jeffrey
N1 - Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 1999
Y1 - 1999
N2 - Growth of long bonos occurs at the growth plate, a layer of cartilage that separates the epiphysis from the metaphysis. Growth plate exhibits spatial polarity. Proliferative chondrocytes undergo terminal differentiation when they approach the metaphyseal, but not the epiphyseal, border of the growth plate. The adjacent bone also exhibits spatial polarity. Metaphyseal, but not epiphyseal, blood vessels and bone cells invade the adjacent growth plate, remodeling it into bone. As a result, the metaphysis, but not the epiphysis, elongates over time. To determine whether cartilage polarity determines bone polarity and/or whether bone polarity determines cartilage polarity, rabbit distal ulnar growth plates were excised, inverted, and reimplanted in their original beds. Thus, cartilage polarity was inverted relative to bone polarity. Histological examination showed that the inverted cartilage polarity was maintained over time. In contrast, the polarity of the adjacent bone reversed after surgery, to match that of the cartilage. Blood vessel and bone cell invasion ceased in the metaphysis and arose in the epiphysis. Longitudinal bone growth (measured with weekly radiographs) occurred at the epiphyseal, not at the metaphyseal, surface of the growth plate. We conclude that the polarity of growth plate cartilage is determined by intrinsic factors. The cartilage polarity then determines the polarity of the adjacent bone and, consequently, the functional polarity of longitudinal bone growth.
AB - Growth of long bonos occurs at the growth plate, a layer of cartilage that separates the epiphysis from the metaphysis. Growth plate exhibits spatial polarity. Proliferative chondrocytes undergo terminal differentiation when they approach the metaphyseal, but not the epiphyseal, border of the growth plate. The adjacent bone also exhibits spatial polarity. Metaphyseal, but not epiphyseal, blood vessels and bone cells invade the adjacent growth plate, remodeling it into bone. As a result, the metaphysis, but not the epiphysis, elongates over time. To determine whether cartilage polarity determines bone polarity and/or whether bone polarity determines cartilage polarity, rabbit distal ulnar growth plates were excised, inverted, and reimplanted in their original beds. Thus, cartilage polarity was inverted relative to bone polarity. Histological examination showed that the inverted cartilage polarity was maintained over time. In contrast, the polarity of the adjacent bone reversed after surgery, to match that of the cartilage. Blood vessel and bone cell invasion ceased in the metaphysis and arose in the epiphysis. Longitudinal bone growth (measured with weekly radiographs) occurred at the epiphyseal, not at the metaphyseal, surface of the growth plate. We conclude that the polarity of growth plate cartilage is determined by intrinsic factors. The cartilage polarity then determines the polarity of the adjacent bone and, consequently, the functional polarity of longitudinal bone growth.
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U2 - 10.1210/endo.140.2.6513
DO - 10.1210/endo.140.2.6513
M3 - Article
C2 - 9927329
AN - SCOPUS:0032960895
VL - 140
SP - 958
EP - 962
JO - Endocrinology
JF - Endocrinology
SN - 0013-7227
IS - 2
ER -