Search PubMed⌕ Search

Biomedical subjects

K Kino

Publications and source records attributed to K Kino.

At least 163 records · Page 9Linked to original sources
PubMed1986

The effect of single essential amino acid deprivation on chick growth and nitrogen and energy balances at ad libitum- and equalized-food intakes.

Diets completely devoid of single essential amino acids were fed to chicks from Day 14 to Day 24 after hatching to investigate the effect on chick growth and nitrogen and energy balances under ad libitum- and equalized-feeding conditions. The effects were different depending upon the amino acid omitted from the diet and were significantly associated with voluntary food intake. Among the essential amino acids, lysine and histidine had the least effect and methionine plus cystine had the severest effect. With equalized-food intake, body weight loss and the reduction in nitrogen balance were diminished by about 44 and 29%, respectively, and the differences in energy utilization disappeared. The possible factors that may explain the nutritional specificity of amino acids are discussed.

Amino Acids, Essential↗
PubMed1986

Improvement of body weight and nitrogen balance of chicks fed histidine-free or lysine-free diets with supplementation of graded levels of sulfur-containing amino acids.

To demonstrate the nutritional specificity of essential amino acids, body weight change and nitrogen balance were compared in chicks equalized-fed a histidine-free or lysine-free diet with 0, 20, 40, 60, 80, or 100% requirement of sulfur-containing amino acids (SAA). With an increase of SAA level up to 40% of its requirement, body weight and nitrogen balance increased irrespective of complete deficiency of histidine or lysine. Above 40% of the SAA requirement, these parameters reached plateaus. The intersection points of the two regression lines at which the responses of body weight change and nitrogen balance altered were 49.8 and 52.1% in the chicks fed the histidine-free diet and 44.7 and 32.6% in the chicks fed the lysine-free diet, respectively. These values are quite agreeable with the estimate of the nutritional score of the amino acid mixtures in an earlier report (Kino and Okumura, 1986). It was demonstrated that the effect of essential amino acid deficiency does not always directly associate with the percentage deficit relative to its requirement, and there exists nutritional specificity of essential amino acids.

Amino Acids, Sulfur↗
PubMed1982

Kinetic aspects of hemoglobin.haptoglobin-receptor interaction in rat liver plasma membranes, isolated liver cells, and liver cells in primary culture.

125I-Hemoglobin.haptoglobin injected intravenously into rats was incorporated into liver parenchymal cells as evidenced by a cell separation technique. A mixture of freshly isolated liver parenchymal and nonparenchymal cells failed to internalize and degrade the 125I-hemoglobin.haptoglobin added, although it retained the ability to bind the molecule. The liver parenchymal cells in primary culture also lacked the ability to degrade 125I-hemoglobin.haptoglobin, although they bound the molecule more extensively as compared with the freshly isolated liver cells. It was confirmed that the 125I-hemoglobin.haptoglobin which was bound to the freshly isolated liver parenchymal cells localized on the outer surface of liver plasma membranes. Scatchard plots revealed the existence of two binding sites for 125I-hemoglobin-haptoglobin on the isolated liver plasma membrane: an apparent high affinity binding site (Kd = 1.3 X 10(-7) M) and an apparent low affinity binding site (Kd = 4.0 X 10(-6) M) at 37 degrees C. In contrast, freshly isolated liver parenchymal cells had only an apparent low affinity binding site (Kd = 1.4 X 10(-6) M) at 37 degrees C. Impairment of the apparent high affinity binding site during the isolation procedure with collagenase seemed to be related to loss of the ability to internalize and degrade the 125I-hemoglobin.haptoglobin molecules into the freshly isolated liver parenchymal cells or liver parenchymal cells in primary culture.

Animals↗
PubMed1981

Catabolism of globin-haptoglobin in liver cells after intravenous administration of hemoglobin-haptoglobin to rats.

The intracellular site of uptake and degradation of globin-haptoglobin, the protein moiety of hemoglobin-haptoglobin, in rat liver cells was investigated in vivo. Hemoglobin-haptoglobin, administered intravenously to rats, is cleared from circulation and incorporated exclusively into liver parenchymal cells through the receptor specific for the molecule (Kino, K., Tsunoo, H., Higa, Y., Takami, M., Hamaguchi, H., and Nakajima, H. (1980) J. Biol. Chem. 255, 9616-9620). Intrahepatocellular distribution of radioactivity was determined after intravenous administration of (125I-hemoglobin)-haptoglobin or hemoglobin-(125I-haptoglobin) to rats. The 125I-labeled hemoglobin-haptoglobin was incorporated first in organelles of low density (density range, 1.05-1.07 g/ml) recovered in Golgi subfractions of the liver cells in a substantially intact form. The organelles progressively acquired a higher density, presumably through fusion with primary lysosomes. In the resulting organelles of high density (density range, 1.07-1.15 g/ml), which are probably secondary lysosomes, hemoglobin-haptoglobin first dissociated symmetrically to yield two 82,000-dalton subunits by a limited proteolysis, and further digestion of the constituent polypeptide chains seemed to proceed thereafter in the organelles during the transport process across the cells.

Animals↗
PubMed1980

Hemoglobin-haptoglobin receptor in rat liver plasma membrane.

The presence of a receptor specific for the hemoglobin . haptoglobin complex is demonstrated in rat liver plasma membranes. Hemoglobin . haptoglobin complex, administered intravenously to rats, was cleared from the circulation at a constant rate with exclusive incorporation of the molecule into hepatocytes. This incorporation was unaffected by the simultaneous injection of asialoglycoprotein or heme . hemopexin complex. In vitro experiments with isolated liver plasma membranes indicated the absence of competitive binding of these molecules to the membrane and suggested that this receptor might recognize an altered conformation of the haptoglobin moiety of the complex resulting from the binding with hemoglobin. These observations suggest that the mechanism of recognition and binding of hemoglobin . haptoglobin complex by the receptor is different from that of the asialoglycoprotein receptor or heme . hemopexin receptor.

Animals↗