An immunohistochemical study of epithelial cells in the posterior lobe and pars tuberalis of the human adult pituitary gland

Summary Pituitary glands were examined using reference staining (hematoxylin and eosin, periodic acid-Schiff and alcian blue) and the peroxidase-labeled antibody method, for 1) invading anterior cells in the posterior lobe, 2) intermediate colloid forming follicles, and 3) pars tuberalis cells.The results showed: 1) that the majority of cases possessed invading anterior cells of various amount. Most of these cells were positive for ACTH^1–18, ACTH^17–39 and -MSH. However, on a few occasions, scattered GH, PRL, FSH, FSH, LH and even TSH cells were also present. 2) Colloid forming follicular cells were mostly ACTH cells, but also contained occasional other hormone-secreting cells. Hormone negative cells were correlated with salivary type epithelium. Well established acinic type salivary glands and ciliated epithelium were negative for any hormones immunohistochemically. 3) Pars tuberalis cells were predominantly gonadotrophs but also included TSH and ACTH cells. Some cells appeared to contain both FSH and LH. When these cells underwent squamous metaplasia, they seemed to lose their hormone secreting activity.Part of this study was supported by a Grant-in-Aid for Cancer Research from the Ministry of Education, Science and Culture, Japan     

Thermal denaturation of cytochromes c of horse cow, and Candida krusei in aqueous guanidine hydrochloride.

Thermal denaturation of cytochromes c of horse, cow, and Candida krusei in aqueous guanidine hydrochloride in the neutral pH region was studied by means of absorption and optical rotation measurements. The values of standard free energy change upon denaturation were estimated over the temperature range from 3 to 51 degrees C. Large differences in the heat capacity of the native and denatured states amounting to several kcal/mol-deg were obtained for all three kinds of cytochromes c. These lead to a change in the sign of both the enthalpy and entropy change of denaturation, with maximum stability of the native state at 12 degrees C for horse and bovine cytochromes c and at 9 degrees C for Candida krusei.     

Origin of hydrogen atoms in the fatty acids synthesized with yeast fatty acid synthetase.

The mechanism of hydrogen incorporation into fatty acids was investigated with an enzyme preparation from baker's yeast. Fatty acids synthesized from malonyl-CoA and acetyl-CoA in the presence of D2O or stereospecifically deuterium-labeled NADPH were isolated and analyzed by mass chromatography to examine the localization of deuterium atoms in the molecule. The following results were obtained: 1. Hydrogen atoms from water were found on the even-numbered methylene carbon atoms (2-hydrogen atoms per carbon atom). The second hydrogen atom was incorporated as the result of hydrogen exchange phenomenon between the methylene group of malonyl CoA and water. 2. HB hydrogen of NADPH was used for beta-ketoacyl reductase. 3. HB hydrogen of NADPH was also used for enoyl reductase. 4. Hydrogen atoms from HB position of NADPH were found on the odd-numbered methylene carbon atoms (2-hydrogen atoms per carbon atom).     

Cerulenin resistance in a cerulenin-producing fungus. Isolation of cerulenin insensitive fatty acid synthetase

Cerulenin, an antifungal antibiotic isolated from a culture filtrate of Cephalosporium caerulens, is a potent inhibitor of fatty acid synthetase systems. This antibiotic specifically blocks the activity of β-ketoacyl thioester synthetase (condensing enzyme). The mechanism of the resistance of C. caerulens to cerulenin was investigated. The rate of growth in medium containing up to 100 gmg/ml cerulenin was as rapid as that in cerulenin-free medium. At a cerulenin concentration of 300 μg/ml, the rate of growth was still more than half that of the control. The addition of cerulenin (200 μg/ml) to a culture of growing cells has almost no effect on the incorporation of [${}^{14}\text{C}$]acetate into cellular lipids. Fatty acid synthetase was purified from C. caerulens to homogeneity. Properties of this fatty acid synthetase were almost the same as those of yeast fatty acid synthetase except for the sensitivity to cerulenin. C. caerulens synthetase is much less sensitive to cerulenin than fatty acid synthetases from other sources. These findings suggested that the insensitivity of C. caerulens fatty acid synthetase plays an important role in the cerulenin resistance of this fungus.     

A specific concanavalin A-mediated binding of bovine serum α-mannosidase to cultured human skin fibroblasts

A specific elevation of cell-associated α-mannosidase was observed in human skin fibroblasts cultured with concanavalin A for 12–72 hours. There was a latency of several hours before the increase of the enzyme activity occurred. When the cells were washed with α-methylmannoside, α-mannosidase activity was not increased. Other lysosomal enzymes including β-mannosidase showed a slight decrease in activity. It was concluded that the elevation of this enzyme activity was the result of a specific binding to the cell surface mediated by concanavalin A.     

Effect of auxin and other hormones on the metabolic response to wounding in sweet potato roots

In roots of sweet potato (Ipomoea batatas Lam. cv. Kokei 14),the metabolic response to wounding was remarkable only in theproximal side. We assumed that the polarity resulted from apolar movement of indole-3-acetic acid (IAA) produced in thecut surface (8). As the metabolic response was slight in thedistal side, the effect of IAA and the other plant hormoneson the development of various enzyme activities was examinedin this side. Increases in activities of L-phenylalanine ammonia-lyase,acid invertase, NADPHa₂ : cytochrome c oxidoreductase, peroxidase,cytochrome c : O₂ oxidoreductase and o-diphenol oxidase, whichdeveloped in response to wounding, were stimulated by the treatmentwith IAA. Gibberellic acid had a stimulative effect on the developmentof only acid invertase activity. Abscisic acid and kinetin hadlittle effect. The results strongly support our hypothesis thatIAA plays an important role in the metabolic response to wounding. (Received September 29, 1979; )     

Electrophoresis of mutant proteins in inherited diseases

The electrophoretic approaches for detection of mutant proteins in inherited diseases are briefly reviewed and discussed. Mutation of a protein, known to be associated with a specific inherited disease, is detected by immunoblotting, immunoprecipitation or enzyme staining, combined with various electrophoretic techniques. Some instrumental and technological devices for two-dimensional electrophoresis have been reported for the screening of mutant proteins in diseases of currently unknown etiology.     

Flow cytometric analysis of lipid droplet formation in cells of the human monocytic cell line, U937.

Active uptake of a free fatty acid, oleate, and its incorporation into triacylglycerol and phospholipid in the human monocytic cell line, U937, was identified using 14C-labelled oleate. Excess triacylglycerol accumulates in the form of lipid droplets in the cytoplasm. The extent of lipid droplet formation in each cell can be assessed in the absence of any staining by 90 degrees light scatter intensity, one of the basic parameters of flow cytometry.     

Establishment and characterization of new cell lines from human renal cell carcinoma

We have characterized seven human renal cell carcinoma cell lines established from primary sites of five patients between 1987 and 1989. Two lines, OUR-20P and OUR-20S, were derived from the OUR-20 cells by cloning with a dilution method 3 months after the primary culture. These three cell lines were tumorigenic in athymic nude mice when inoculated subcutaneously. Examined by a dye uptake method, OUR-20 was highly sensitive to interferon-alpha (IFN-alpha); OUR-20P, OUR-20S and OUR-30 showed slight sensitivities, while the other three cell lines were insensitive. All seven cell lines have been maintained for more than 2 years and over 50 passages in vitro. Cytogenetic analyses performed 1.5 to 3 years after the starts of primary cultures indicated that all seven cell lines, which exhibited different morphologies in phase-contrast micrographs, were aneuploid with modal chromosome numbers 41 to 89.