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101.
Localization of arachidonate 12-lipoxygenase in parenchymal cells of porcine anterior pituitary 总被引:2,自引:0,他引:2
N Ueda A Hiroshima K Natsui F Shinjo T Yoshimoto S Yamamoto K Ii K Gerozissis F Dray 《The Journal of biological chemistry》1990,265(4):2311-2316
12-Lipoxygenases oxygenate arachidonic acid producing its 12S-hydroperoxy derivative and are well known as platelet and leukocyte enzymes. When a peroxidase-linked immunoassay of the enzyme according to the avidin-biotin method was applied to the cytosol fractions from various parts of porcine brain, a considerable amount of the enzyme was found in the anterior pituitary. The enzyme level (about 200 ng/mg cytosol protein) corresponded to about 6% of the enzyme content in porcine peripheral leukocytes. Posterior and intermediate lobes showed about one-tenth of the enzyme level of anterior pituitary. Other parts of porcine brain contained the 12-lipoxygenase in amounts below 7 ng/mg cytosol protein. The cytosol fraction (0.7 mg of protein) of anterior pituitary produced 12S-hydroxy-5,8,10,14-eicosatetraenoic acid from 25 microM arachidonic acid in about 34% conversion at 24 degrees C for 5 min, giving a specific enzyme activity about 3 nmol/min/mg protein. Furthermore, various octadecapolyenoic acids were oxygenated almost as fast as the arachidonate 12-oxygenation. When anterior pituitary was investigated immunohistochemically with anti-12-lipoxygenase antibody, most of the immunostained cells were certain parenchymal cells with granules, which were not blood cells. These biochemical and immunohistochemical results provide a good reason for considering that 12-lipoxygenase does play an important role in pituitary function. 相似文献
102.
Tadami Nagao Mitsumoto Komatsuda Kunihiko Yamauchi Shigeru Arimori 《Journal of cellular physiology》1981,108(2):155-161
In a liquid culture of human bone marrow, the development of fibroblast colonies takes place on days 6 to 9. Twenty percent fetal calf serum is used as the stimulus for fibroblast colony growth. Human bone marrow cells are plated as 2 × 105 cells in the culture. Normal human bone marrow yields 47 ± 4 fibroblasts colonies per 2 × 105 cells plated. Bone marrow fibroblast cultures using agar or methylcellulose restrict colony formation. Marked colony suppression was observed in acute leukemia, and a discrete colony number was observed in hypoplastic anemia. This fibroblast culture method should be applied to a larger number of patients to determine whether it has a pathognomonic value and clinical significance. 相似文献
103.
A supernumerary muscle bundle “M. tubero-femoralis
Fick” of the biceps femoris was found in a female crab-eating monkey in both hindlimbs. 相似文献
104.
M Ueda 《Comptes rendus des séances de la Société de biologie et de ses filiales》1981,175(3):372-376
The effects of calcium and magnesium ions on the corticosterone binding to rat brain cytosol receptor protein(s) were investigated. The increasing amounts of CaCl2 or MgCl2 up to 5.0 mM were added, the specific [3H] corticosterone binding increased 1.3-fold and 1.5 respectively. The addition of MnCl2 and KCl did not affect this binding. The binding of corticosterone with rat brain cytosol receptor(s) were decreased by increasing amounts of EDTA and complete inhibition was observed at concentration equal to and greater than 2.5 mM. Inhibition of this binding by EDTA was less than by EGTA. Either theophylline or dibutyryl cyclic AMP had no effect on this binding. 相似文献
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Koshiro Yoshioka Mitsuo Fujimori Kiwamu Yamaoka Kazuyoshi Ueda 《International journal of biological macromolecules》1982,4(1):55-61
The electric birefringence and circular dichroism spectra of poly(l-ornithine hydrobromide) have been measured in ethanol/water, 2-propanol/water and tertiary butyl alcohol/water mixtures of various compositions. This charged polypeptide underwent a transition from the coil conformation to the helical conformation at high alcohol content in every case tested. Anomalous birefringence signals, indicative of a field-induced helix-to-coil transition. were observed at high electric fields only in the case of ethanol/water mixtures. The reversing-pulse electric birefringence of this polypeptide has been studied in ethanol/water mixtures and in neutral aqueous solution. Upon rapid reversal of the pulse field, no transient could be observed. This confirms that the electric-field orientation of poly(l-ornithine hydrobromide) results predominantly from the contribution of the counterion-induced dipole moment, regardless of its molecular conformations. It is very probable that the backbone permanent dipole moment of the helical conformation is largely suppressed by the counterion-induced dipole moment in the ionized form. 相似文献
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An acromegalic patient with galactorrhea was treated with an ergot alkaloid, 2-Br-alpha-ergocryptine (CB-154). Serum prolactin decreased rapidly to normal level by CB-154 and the complete cessation of galactorrhea was noted. The inhibitory effect of CB-154 On growth hormone (GH) release was also noted, but slight. The mechanism of inhibitory action of CB-154 on both prolactin and GH secretion was discussed in connection with the experimental model of pituitary tumors, in which both hormones were produced by a single type of tumor cells. The discontinuation of CB-154 treatment was associated with the return of both prolactin and GH levels to the initial high values with resumption of galactorrhea. 相似文献