The major objective of the proposed study is to investigate the role of prostaglandins (PGs) and cyclic AMP (cAMP) in cytodifferentiation utilizing chondrogenesis as an in vitro model system. Both cAMP and PGs have been implicated as internal and external regulatory factors, respectively, in chondrogenesis, however, the basis for the proposed regulatory influence of these factors is still unknown. The proposed study will employ high density tissue culture of cells from chick limb buds as a model system for chondrogenesis. In this system, chondrogenesis proceeds through an orderly sequence of morphological and biochemical events, which have been well characterized by previous investigations and which mark specific temporal changes which accompany the expression of the mature phenotype. The study will have three major objectives: 1. To determine the distribution and activation characteristics of cAMP-dependent protein kinase during chondrogenesis and effects of PGs on activation of this enzyme in intact limb cells. 2. To determinme the distribution of endogenous substrate proteins phosphorylated during chondrogenesis and the effects of PGs on protein phosphorylation. 3. To determine the type and relative amounts of PGs synthesized by limb bud cells during chondrogenesis. The study will provide important, new information regarding the possible role of PGs and cAMP in limb chondrogenesis which should broaden our understanding of a variety of skeletal defects which occur during embryogenesis.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Research Project (R01)
Project #
1R01HD019017-01A1
Application #
3316169
Study Section
Human Embryology and Development Subcommittee 2 (HED)
Project Start
1986-08-01
Project End
1989-07-31
Budget Start
1986-08-01
Budget End
1987-07-31
Support Year
1
Fiscal Year
1986
Total Cost
Indirect Cost
Name
Wake Forest University Health Sciences
Department
Type
Schools of Medicine
DUNS #
041418799
City
Winston-Salem
State
NC
Country
United States
Zip Code
27106
Biddulph, D M; Dozier, M M; Capehart, A A (2000) Inhibition of prostaglandin synthesis reduces cyclic AMP levels and inhibits chondrogenesis in cultured chick limb mesenchyme. Methods Cell Sci 22:16-Sep
Capehart, A A; Biddulph, D M (1991) Development of PTH-responsive adenylate cyclase activity during chondrogenesis in cultured mesenchyme from chick limb buds. Calcif Tissue Int 48:400-6
Capehart, A A; Biddulph, D M (1991) Effects of a putative prostaglandin E2 antagonist, AH6809, on chondrogenesis in serum-free cultures of chick limb mesenchyme. J Cell Physiol 147:403-11
Biddulph, D M; Capehart, A A; Beasley, T C (1991) Comparative effects of cytosine arabinoside and a prostaglandin E2 antagonist, AH6809, on chondrogenesis in serum-free cultures of chick limb mesenchyme. Exp Cell Res 196:131-3
Capehart, A A; Biddulph, D M; Dozier, M M et al. (1990) Responsiveness of adenylate cyclase to PGE2 and forskolin in isolated cells from micromass cultures of chick limb mesenchyme during chondrogenesis. Prostaglandins 39:167-78
Biddulph, D M; Dozier, M M (1989) Phorbol esters inhibit chondrogenesis in limb mesenchyme by mechanisms independent of PGE2 or cyclic AMP1. Exp Cell Res 185:541-5
Biddulph, D M; Sawyer, L M; Dozier, M M (1988) Chondrogenesis in chick limb mesenchyme in vitro derived from distal limb bud tips: changes in cyclic AMP and in prostaglandin responsiveness. J Cell Physiol 136:81-7
Biddulph, D M; Dozier, M M; Julian, N C et al. (1988) Inhibition of chondrogenesis by retinoic acid in limb mesenchymal cells in vitro: effects on PGE2 and cyclic AMP concentrations. Cell Differ Dev 25:65-75