Cytokines modulate contraction of periosteal explants from rabbit calvariae.
Periosteal explants obtained from rabbit calvariae are introduced as a model system to study contraction of soft connective tissue. Culturing of these explants resulted in a substantial time-dependent decrease of the surface area which coincided with a similar decrease in volume. A 75% reduction of the initial explant surface area was observed after a culture period of 72h in the presence of 10% serum. Also in the absence of serum contraction of explants was found, indicating that serum components were not essential. Following devitalization of the explants no contraction did occur. A strong inhibition of contraction was found following interference with the formation of microfilaments, microtubules or intracellular cyclic-AMP levels by using cytochalasin B, colchicine or dibutyryl-cAMP, respectively. These data indicated that viable cells and an intact cytoskeleton were a prerequisite for contraction to occur. A number of cytokines (EGF, aFGF, bFGF, IGF-1, PDGF, TGF-beta and IL-1alpha) was tested for their ability to influence contraction. IL-1alpha was shown to inhibit contraction from the 48h culture period on. Anti-IL-1alpha-serum completely abolished this effect. The IL-1alpha-inducible inhibition of contraction was also partially blocked by indomethacin. TGF-beta enhanced contraction dose-dependently during the 24-48h culture period, whereas TGF-1 and IL-1alpha, added to the cultures in combination, proved to antagonize each other. The other growth factors did neither influence contraction not the IL-1alpha-induced inhibition of contraction.
van der Zee
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Experimental Oral Biology Group, Department of Periodontology, Academic Centre for Dentistry Amsterdam, University of Amsterdam, The Netherlands.
Everts
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V
Beertsen
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D008841:Actin Cytoskeleton / Q000187:drug effects / Q000502:physiology; D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D003994:Bucladesine / Q000494:pharmacology; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology*; D003078:Colchicine / Q000494:pharmacology; D003094:Collagen / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D000242:Cyclic AMP / Q000378:metabolism; D003571:Cytochalasin B / Q000494:pharmacology; D016207:Cytokines / Q000378:metabolism* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions / Q000502:physiology; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D007213:Indomethacin / Q000494:pharmacology; D007375:Interleukin-1 / Q000037:antagonists & inhibitors; D046529:Microscopy, Electron, Transmission; D008870:Microtubules / Q000187:drug effects / Q000502:physiology; D008954:Models, Biological; D009924:Organ Culture Techniques; D010521:Periosteum / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D011817:Rabbits; D012886:Skull / Q000166:cytology / Q000502:physiology; D013997:Time Factors; D016212:Transforming Growth Factor beta / Q000494:pharmacology; D014945:Wound Healing / Q000187:drug effects / Q000502:physiology*
D000906:Antibodies; D016207:Cytokines; D007375:Interleukin-1; D016212:Transforming Growth Factor beta; D003571:Cytochalasin B; D003994:Bucladesine; D003094:Collagen; D000242:Cyclic AMP; D003078:Colchicine; D007213:Indomethacin