title: A study of growth regulators of renal cortical tubular cells in the rabbit liver.
abstract: Two growth regulators, a growth stimulator for cultured renal tubular cells and a growth inhibitor, were observed in this study in rabbit liver homogenate after a unilateral nephrectomy. These regulators appeared in the liver on the third day after this nephrectomy, decreased on the seventh day, and disappeared by the fourteenth day. The growth stimulatory activity, termed a tubular cell growth factor (TuCGF), was a heat- and acid stable 15 to 20 KDa protein. The additive effects of TuCGF on the epidermal growth factor (EGF), the insulin-like growth factor-I (IGF-I), and the fibroblast growth factor (FGF) were observed; the results suggest that TuCGF differs from EGF, IGF-I, or FGF. In contrast, the growth inhibitory activity, termed a tubular cell growth inhibitor (TuCGI), was a heat- and acid-labile protein with a molecular weight of about 150 to 200 KDa. This factor potently inhibited the DNA synthesis of tubular cells in the presence of insulin and EGF. These results suggest that TuCGI is not identical with transforming growth factor-beta (TGF-beta). The regulation of these activities by target cell density is also discussed.
authors.affiliation: Department of Urology, Nagasaki University School of Medicine, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kanda
authors.forename: K
authors.initials: K
authors.lastname: Nomata
authors.forename: P K
authors.initials: PK
authors.lastname: Saha
authors.forename: N
authors.initials: N
authors.lastname: Nishimura
authors.forename: J
authors.initials: J
authors.lastname: Yamada
authors.forename: H
authors.initials: H
authors.lastname: Kanetake
authors.forename: Y
authors.initials: Y
authors.lastname: Saito
mesh_terms: D000818:Animals; D002455:Cell Division; D006131:Growth Inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D006133:Growth Substances / Q000302:isolation & purification / Q000378:metabolism*; D006984:Hypertrophy; D007668:Kidney / Q000473:pathology; D007684:Kidney Tubules / Q000166:cytology*; D008099:Liver / Q000378:metabolism*; D008297:Male; D011817:Rabbits
chemical_list: D006131:Growth Inhibitors; D006133:Growth Substances