title: Use of a 3T3 cell growth factor assay for the delineation and characterization of humoral trophic factors involved in intestinal adaptation in the rat.
abstract: Indirect evidence has suggested that circulating trophic factors are involved in intestinal adaptation. A 3T3 fibroblast cell culture system was used to more directly delineate the presence of such factors. Rats were divided into four groups: C-unop, those undergoing no surgery; S, those in which a dorsal slit was made; C-op, those in which the peritoneum was incised; and R, those undergoing 80% intestinal resection. At the time of death at 24 h, 1 wk, and 2 wk postoperative, stimulation of DNA synthesis in the 3T3 cells was noted after incubation with platelet-free plasma from the C-op and R groups, and simultaneously an increase in ileal DNA specific activity occurred. Characterization of the plasma fraction with growth factor activity revealed it to have a molecular weight of greater than 6000 but less than 14,000. The factors were resistant to reduction with dithiothreitol, and were partially inactivated by heating to 60 degrees C. The use of a 3T3 cell growth factor assay system now makes it possible to further characterize circulating factors involved in intestinal adaptation.
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D001345:Autoradiography; D001681:Biological Assay / Q000379:methods; D002460:Cell Line; D004247:DNA / Q000096:biosynthesis; D003956:Dialysis; D005347:Fibroblasts; D006133:Growth Substances / Q000032:analysis*; D007082:Ileum / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000502:physiology* / Q000601:surgery; D008297:Male; D008970:Molecular Weight; D051381:Rats; D011919:Rats, Inbred Strains; D012588:Scintillation Counting; D013997:Time Factors
chemical_list: D006133:Growth Substances; D004247:DNA