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Y C LEE

Publications and source records attributed to Y C LEE.

36 records · Page 2Linked to original sources
PubMed1954

Cellular mechanisms of protein metabolism in the nephron. I. The structural aspects of proteinuria; tubular absorption, droplet formation, and the disposal of proteins.

When proteins pass the glomerular filter they are in part directly absorbed by the epithelial cells of the proximal convolution of the nephron with no apparent alteration of the cytological pattern. If the capacity of the tubule cells to thus absorb protein from the tubule fluid is exceeded either by the amount or the nature of the protein the accessory mechanism of droplet formation occurs. This accessory mechanism is an intracellular process in which cytoplasmic elements, the mitochondria with their enzymes, and the absorbed protein combine to form droplets. As the droplets form and then disappear from the renal cells their evolution presents a constantly changing picture depending on the varying nature of their protein and cytoplasmic content. The droplet is therefore not a cytological structure of fixed characteristics (hyaline droplet) but a locus of metabolic activity and varied structural aspect.

Kidney↗
PubMed1954

Cellular mechanisms of protein metabolism in the nephron. II. The histochemical characteristics of protein absorption droplets.

Histochemical methods show not only the presence of absorbed protein in the cellular droplet, but also the general identity of its constituent substances with those of the mitochondrial rodlets. Both contain considerable amounts of phospholipid and probably some PNA. The reactivity of the cytoplasmic constituents in droplet and in rodlet are different, however, since in the droplet these substances stain more intensely. As judged by variations observed in this intensity during the evolution of the droplet, these constituents and the absorbed protein vary in their proportions and amount. The droplet would appear to be a highly active center of protein metabolism.

Cytoplasm↗
PubMed1954

Cellular mechanisms of protein metabolism in the nephron. III. The histochemical characteristics of amino acid droplets.

1. The cells of the proximal convolutions of the rat can be filled with fine droplets by the administration of certain amino acids in non-toxic dosage. 2. These minute droplets resemble in their Gram positivity and in their phospholipid and PNA content on biochemical analysis (3) the larger droplets that form in the cells of the proximal convolution during the absorption of certain proteins. 3. The positive or negative reaction to 3 specific histochemical procedures of the fine droplets forming after administration of 7 amino acids gave such a high positive correlation with theoretical assumption as to warrant the following inferences: (a) that the methods are specific under the conditions of the experiment; (b) that the droplets contain a higher concentration of the administered amino acid than the general cytoplasm of the cells which contain them. 4. The mitochondrial rodlets of epithelium of the proximal convolution contain sulfhydryl in high concentration, a finding which correlates well with their enzymatic activity.

Amino Acids↗