Shoichi Suemori

Partial purification and characterization of hepatocyte proliferation stimulatory factor from liver of pats treated with D-galactosamine

The partial purification and characterization of a hepatocyte proliferation stimulatory factor (HPSF) isolated from the liver of D-galactosamine-treated rats are described. The HPSF was a heat-labile, acid-stable and trypsin-sensitive protein. The partially purified HPSF stimulated DNA synthesis and increased the labeling index of parenchymal hepatocytes at 5 micrograms/ml and maximally at 50 micrograms/ml. The effect of HPSF in stimulating DNA synthesis was synergistic with that of insulin plus epidermal growth factor (EGF). The HPSF was scarcely detected in normal rat liver. The results obtained indicate that this HPSF is distinct from insulin, multiplication-stimulating activity (MSA), EGF and other hepatocyte growth factors previously reported, and suggest a plausible role for HPSF in the regeneration of liver tissue following hepatotoxic damage.

Effect of glucagon on galactose tolerance test in regenerating rat liver.

著者らは,肝予備能検査の中でガラクトース負荷試験が肝重量と関係なく代謝機能を有する残存肝細胞数と密接な関連を有する事を報告した.また,再生肝のガラクトース代謝にglucose-6-phosphatase活性が影響を及ぼしている事を報告したが,本論文では諸酵素を活性化すると考えられるグルカゴンの再生肝に及ぼす効果を検討した.グルカゴン非投与再生肝では肝切3日後に血中ガラクトース半減期が最延長したが,グルカゴン投与再生肝では有意の短縮を認めた.肝切3日後のグルカゴン投与再生肝と非投与再生肝におけるglucose-6-phosphatase活性と血中乳酸値について検討しグルカゴン投与再生肝においてglucose-6-phosphatase活性の上昇と血中乳酸値の低下を認めた.従ってグルカゴンは部分肝切除後の肝予備能の低下を防ぎ,肝細胞の有する代謝機能を保護することが示唆された.