title: Insulin and thyroid hormone stimulation of histotypic organogenesis and proteoglycan synthesis in seven-day chick embryo liver.
abstract: Livers from seven-day chick embryos were dissociated into single cells and the cells were allowed to aggregate in Dulbecco's Modified Eagle's Medium-12% foetal calf serum, 1-3H-glycosamine, 2-14C-glycine and hormones. Insulin, 10(-6)M, accelerated the rate of aggregation and resulted in larger aggregates than the controls, without added hormone . 3, 3', 5 Tri-iodo-thyronine, 10(-8)M, gave rise to slightly smaller aggregates than control aliquots. Incorporation of 2-14C-glycine and 1-3H-glucosamine was almost linear the first 36 hours whereupon incorporation reached a plateau at 48 hours. Insulin, 10(-6)M, enhanced 1-3H-glucosamine incorporation 54% and glycine incorporation to 42%. Tri-iodo-thyronine stimulated 1-3H-glucosamine 110% and glycine incorporation by 68%. When both insulin and tri-iodo-thyronine were added to the culture medium, glucosamine incorporation was augmented by 156% and glycine incorporation was stimulated by 77%. These findings are interpreted to indicate that synthesis of glycoproteins and proteo-glycosaminylglycans favours histogenesis or specific cell orientation and cell-cell interactions. Hormones had only a small effect on the incorporation of glycine and glycosamine into the soluble media components.
mesh_terms: D000818:Animals; D002642:Chick Embryo; D004305:Dose-Response Relationship, Drug; D005944:Glucosamine / Q000378:metabolism; D005998:Glycine / Q000378:metabolism; D007328:Insulin / Q000494:pharmacology*; D008099:Liver / Q000196:embryology*; D009024:Morphogenesis / Q000187:drug effects; D011509:Proteoglycans / Q000096:biosynthesis*; D014284:Triiodothyronine / Q000494:pharmacology*
chemical_list: D007328:Insulin; D011509:Proteoglycans; D014284:Triiodothyronine; D005944:Glucosamine; D005998:Glycine