title: Changes in muscle mRNAs for hexokinase, phosphofructokinase-1 and glycogen synthase in acute and persistent hypoglycemia induced by tolbutamide in chickens.
abstract: To elucidate the specificity of glucose metabolism in chicken skeletal muscle, changes in mRNA levels of hexokinase I (HKI), hexokinase II (HKII), phosphofructokinase-1 (PFK-1) and glycogen synthase (GS) were characterized in acute and persistent hypoglycemia induced by tolbutamide administration. In acute hypoglycemia, induced by a single dose of tolbutamide (100 mg/kg body mass), HKII, PFK-1 and GS mRNA levels remained unchanged; however, levels of HKI mRNA and glucose transporter 1 (GLUT1) were significantly increased 4 h after administration. In persistent hypoglycemia, induced by sequential administration of tolbutamide (100 mg/kg body mass) 3 times a day for 5 days, GS mRNA was significantly increased at day 5, while HKI, HKII and PFK-1 mRNA levels remained unchanged. These results suggest that HKI is responsible for glucose transport into skeletal muscle in acute hypoglycemia and that glucose preferentially enters the glycogenic pathway before the glycolytic pathway in persistently hypoglycemic chickens.
authors.affiliation: Animal Nutrition, Division of Life Sciences, Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Seki
authors.forename: Kan
authors.initials: K
authors.lastname: Sato
authors.forename: Yukio
authors.initials: Y
authors.lastname: Akiba
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002645:Chickens; D018076:DNA, Complementary / Q000378:metabolism; D006006:Glycogen Synthase / Q000235:genetics / Q000378:metabolism*; D006593:Hexokinase / Q000235:genetics / Q000378:metabolism*; D007003:Hypoglycemia / Q000139:chemically induced / Q000378:metabolism*; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000737:chemistry / Q000201:enzymology / Q000378:metabolism*; D010732:Phosphofructokinase-1 / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014044:Tolbutamide / Q000494:pharmacology*
chemical_list: D018076:DNA, Complementary; D012333:RNA, Messenger; D014044:Tolbutamide; D006006:Glycogen Synthase; D006593:Hexokinase; D010732:Phosphofructokinase-1