title: Cholera toxin and dibutyryl cyclic-AMP stimulate the growth of epithelial cells derived from epithelial rests from porcine periodontal ligament.
abstract: The epithelial cells (E-cells) grew best at high (greater than 5 per cent) concentrations of fetal bovine serum (FBS). Growth could be obtained at low concentrations of dialysed FBS (DFBS) if the medium (alpha-MEM) was modified so that the levels of Ca2+ and K+ were reduced to 0.1 and 1.0 mM, respectively (beta-MEM). The addition of 0.5 per cent DFBS to the beta-MEM did not initiate good growth but was sufficiently supportive to enable the effects of various growth promoters to be tested. Cholera toxin and dibutyryl cyclic-3'5'-adenosine monophosphate (Bt2cAMP), which are known to increase intracellular cAMP levels, at concentrations of 1 ng/ml and 0.5 mM, respectively increased cell number. Cholera toxin caused the E-cells to be more flattened when viewed by phase-contrast; this appeared to be due to spread of the cells. No difference in cell-size distributions obtained between the trypsinized E-cells grown in the presence or absence of cholera toxin was observed. Epithelial proliferation that occurs in dental cysts could result from a rise in intracellular cAMP levels in epithelial cell rests.
mesh_terms: D000818:Animals; D003994:Bucladesine / Q000494:pharmacology*; D002452:Cell Count; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D002772:Cholera Toxin / Q000494:pharmacology*; D003470:Culture Media; D004847:Epithelial Cells; D004848:Epithelium / Q000187:drug effects; D008858:Microscopy, Phase-Contrast; D010513:Periodontal Ligament / Q000166:cytology / Q000187:drug effects*; D013552:Swine
chemical_list: D003470:Culture Media; D003994:Bucladesine; D002772:Cholera Toxin