Jun-ichi Okumura

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By using three nonviral transfection methods, i.e., microparticle bombardment, lipofection and electroporation, the transfection efficiency and the expression intensity of a lacZ reporter gene were compared in developing chicken embryos in ovo. Of the three transfection methods employed, electroporation conferred the strongest expression of the bacterial(More)
1. Energy cost of whole-body protein synthesis was measured in vivo in chicks by comparing the changes in protein synthesis and heat production after the administration of cycloheximide, an inhibitor of protein synthesis. 2. Incorporation of phenylalanine into whole-body protein fraction was promptly inhibited after the intravenous injection of(More)
To investigate the effect of nitric oxide (NO) on food intake in the chicken, L-NG-nitro-arginine methyl ester HCl (L-NNA), an inhibitor of NO synthase, was applied. When i.p. administered, L-NNA significantly inhibited the food intake of broiler chickens in a dose response manner. Food ingestion was also depressed by the i.c.v. injection of L-NNA in a dose(More)
The relationship between nutritional status and insulin-like growth factor binding protein-2 (IGFBP-2) gene expression in chickens was studied. Chickens (6 wk old) were food deprived for 2 d and then refed. IGFBP-2 mRNA in the brain was significantly decreased by food deprivation and levels did not increase when birds were refed for 24 h. Gizzard and(More)
Glucagon-like peptide-1 (GLP-1), structurally similar to glucagon, is synthesized from a larger precursor, preproglucagon, and has been postulated to be a novel incretin. Recently, it was reported that central administration of GLP-1 decreased food intake in rats. The amino acid sequences of GLP-1 are identical in all mammals, and chicken GLP-1 exhibits a(More)
We investigated the influence of refeeding food-deprived chicks with either protein, carbohydrate, fat or combinations thereof on the rates of liver and muscle protein synthesis. After 2 d of food-deprivation, chicks were given individual or mixed protein, carbohydrate and fat. At 30 min after refeeding, the protein fractional synthesis rate (K(s)) was(More)
1. The effect of L-carnitine supplemented into experimental diets with varying dietary protein concentrations (50, 200 and 400 g/kg) on body weight gain and plasma insulin-like growth factor-I (IGF-I) concentration in chicks was examined. 2. Dietary L-carnitine supplementation provided 0, 200, 500 and 1000 mg/kg. Chicks were given the diet ad libitum for 10(More)
1. We examined the influence of refeeding after 2 d of fasting on plasma insulin-like growth factor-I (IGF-I) concentration and hepatic IGF-I gene expression in chickens at 6 weeks of age. 2. Hepatic IGF-I mRNA was measured by ribonuclease protection assay and plasma IGF-I concentration was determined by radioimmunoassay. 3. Plasma IGF-I concentration(More)
In order to attain foreign gene expression in vivo in the testis of living mice, chloramphenicol acetyltransferase (CAT), firefly luciferase and bacterial lacZ reporter genes were transfected by microparticle bombardment and electroporation. The results showed that CAT reporter gene was expressed in a dose-dependent fashion. The X-gal staining showed that(More)
The importance of egg albumen content in whole-body protein synthesis was investigated in developing chicken embryos by using lines genetically selected for high and low albumen contents and by removing albumen from eggs before incubation. 2. Whole-body protein synthesis was estimated by injecting L-[15N]-phenylalanine intravenously on day 12 of incubation.(More)