Bone growth in children and adolescent animals occurs by endochondral ossification in cartilaginous growth plates at the ends of long bones. In any given growth plate, chondrocytes occur in a characteristic spatial organization that also is a representation of the temporal progression of individual chondrocytic differentiation. A unique aspect of the differentiation process of the growth plate chondrocyte is the translation of this differentiation into growth. This research focuses on understanding the biology of growth plate cartilage in relationship to growth. The long-term objective of this research is to understand the multiple control mechanisms involved in regulating the rate and extent of long bone growth from embryonic patterning, to interactions of chondrocytes with their matrix to initiate/cease specific gene expression, to systemic hormonal controls, to local paracrine, autocrine and biomechanical controls over growth plate activity. The specific objective of this proposal is to understand control mechanisms, acting at the level of the chondrocyte, that are responsible for coordinated long bone growth in multiple growth plates within the person/animal at one point in time, and in one growth plate over time. This objective is extended to include understanding of perturbations of normal growth with the intent of understanding the possibilities and limitations of intervention procedures for the correction of abnormalities of long bone growth. Using a variety of in situ based microscopical, stereological, and experimental techniques, the four Specific Aims of our current proposal are: 1. To test the hypothesis that variables associated with cell cycle parameters of chondrocytes within the proliferative zone are significant determinants of the variability in rate of growth of different growth plates. 2. To test the hypothesis that overall growth is controlled by volume changes translated into appropriate cellular shape changes during hypertrophy. 3. To test the hypothesis that control points for the regulation of growth occur at specific transition points. 4. To test the hypothesis the alterations of rate of growth achieved by externally mediated perturbations are controlled at the level of the hypertrophic chondrocyte.

Agency
National Institute of Health (NIH)
Institute
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Type
Research Project (R01)
Project #
5R01AR035155-10
Application #
2079017
Study Section
Orthopedics and Musculoskeletal Study Section (ORTH)
Project Start
1985-07-01
Project End
1998-02-28
Budget Start
1995-03-01
Budget End
1996-02-29
Support Year
10
Fiscal Year
1995
Total Cost
Indirect Cost
Name
University of Wisconsin Madison
Department
Biology
Type
Schools of Veterinary Medicine
DUNS #
161202122
City
Madison
State
WI
Country
United States
Zip Code
53715
Sansone, Jason M; Wilsman, Norman J; Leiferman, Ellen M et al. (2009) The effect of periosteal resection on tibial growth velocity measured by microtransducer technology in lambs. J Pediatr Orthop 29:61-7
Sansone, Jason M; Wilsman, Norman J; Leiferman, Ellen M et al. (2009) The effect of fluoroquinolone antibiotics on growing cartilage in the lamb model. J Pediatr Orthop 29:189-95
Wilsman, Norman J; Bernardini, Elizabeth S; Leiferman, Ellen et al. (2008) Age and pattern of the onset of differential growth among growth plates in rats. J Orthop Res 26:1457-65
Grover, Joel P; Vanderby, Ray; Leiferman, Ellen M et al. (2007) Mechanical behavior of the lamb growth plate in response to asymmetrical loading: a model for Blount disease. J Pediatr Orthop 27:485-92
Noonan, Kenneth J; Farnum, Cornelia E; Leiferman, Ellen M et al. (2004) Growing pains: are they due to increased growth during recumbency as documented in a lamb model? J Pediatr Orthop 24:726-31
Farnum, Cornelia E; Lee, Andrea O; O'Hara, Kathleen et al. (2003) Effect of short-term fasting on bone elongation rates: an analysis of catch-up growth in young male rats. Pediatr Res 53:33-41
Farnum, C E; Nixon, A; Lee, A O et al. (2000) Quantitative three-dimensional analysis of chondrocytic kinetic responses to short-term stapling of the rat proximal tibial growth plate. Cells Tissues Organs 167:247-58
Bailon-Plaza, A; Lee, A O; Veson, E C et al. (1999) BMP-5 deficiency alters chondrocytic activity in the mouse proximal tibial growth plate. Bone 24:211-6
Wilsman, N J; Farnum, C E; Leiferman, E M et al. (1996) Differential growth by growth plates as a function of multiple parameters of chondrocytic kinetics. J Orthop Res 14:927-36
Wilsman, N J; Farnum, C E; Green, E M et al. (1996) Cell cycle analysis of proliferative zone chondrocytes in growth plates elongating at different rates. J Orthop Res 14:562-72

Showing the most recent 10 out of 15 publications