The effect of insulin-like growth factor-I and human growth hormone on periodontal ligament fibroblast morphology, growth pattern, DNA synthesis, and receptor binding.
Repopulation of the detached root surface by cells from the periodontal ligament (PDL) is a prerequisite for new attachment formation. Stimulation of PDL-cell growth may therefore serve as an essential method to enhance formation of new attachment. Studies have demonstrated that insulin-like growth factor-I (IGF-I) has a mitogenic effect on fibroblasts originating from various connective tissues and cell-lines. Further, human growth hormone (hGH) is known to regulate the plasma concentration of IGF-I and to mediate cellular biological effects. In the present study we examined the effect of IGF-I and hGH on morphology, growth pattern, and DNA synthesis. The expression of IGF-I and hGH receptors on the surface of cultured PDL fibroblasts is also described. A primary fibroblastic cell line was established from rat PDL tissue, and blind, photographic recordings of morphology and growth pattern, as well as incorporation of [3H]thymidine in cellular DNA, was carried out in the presence and absence of IGF-I and hGH. The presence of specific membrane receptors was investigated by binding of [125I]IGF-I and [125I]hGH. The analysis of photographs showed that IGF-I and hGH had no effect on morphology and growth pattern. Incorporation of 3H-thymidine, however, was increased in a dose-dependent manner by IGF-I, whereas hGH alone or in combination with IGF-I produced no dose-dependent response. Maximum effect (% of control) on DNA synthesis was 176% for IGF-I and 91% for hGH.(ABSTRACT TRUNCATED AT 250 WORDS)
Blom
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Holmstrup
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Dabelsteen
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D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D048429:Cell Size / Q000187:drug effects; D003599:Cytoskeleton / Q000737:chemistry; D004247:DNA / Q000096:biosynthesis* / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000737:chemistry / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D013006:Growth Hormone / Q000008:administration & dosage / Q000494:pharmacology*; D007334:Insulin-Like Growth Factor I / Q000008:administration & dosage / Q000494:pharmacology*; D007457:Iodine Radioisotopes; D010513:Periodontal Ligament / Q000737:chemistry / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D017526:Receptor, IGF Type 1 / Q000187:drug effects* / Q000378:metabolism; D011986:Receptors, Somatotropin / Q000187:drug effects* / Q000378:metabolism; D013936:Thymidine / Q000378:metabolism; D014316:Tritium
D007457:Iodine Radioisotopes; D011986:Receptors, Somatotropin; D014316:Tritium; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone; D004247:DNA; D017526:Receptor, IGF Type 1; D013936:Thymidine