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M Ota

Publications and source records attributed to M Ota.

At least 325 records · Page 18Linked to original sources
PubMed1985

Characterization of nontransformed and transformed androgen receptor from rat submandibular gland.

Rat submandibular gland cytosol contained androgen receptor which had a single class of specific binding and an apparent dissociation constant of (1.1-1.2) X 10(-9) M. The process of transformation was investigated by a slightly modified minicolumn method in which the transformed receptor complexes were separated from the nontransformed receptor and meroreceptor. 10 mM ATP or pyrophosphate at 0 degrees C induced transformation of androgen receptor as did heat or salt treatment. 20 mM of sodium molybdate completely inhibited transformation that resulted from ATP, heat or salt treatment. The nontransformed androgen receptor complexes sedimented at 8 S and eluted at 250-260 mM KCl from DEAE-Sephacel, and its molecular weight was found to be 220 000 on Sephacryl S300 gel chromatography. On the other hand, the transformed androgen receptor complexes sedimented at 4.1-4.3 S (ATP or KCl treatment) or 3.5-3.8 S (heat treatment) and eluted at 60-80 mM KCl from DEAE-Sephacel. The molecular weight of the transformed androgen receptor complexes was 80 000-85 000 (ATP or KCl treatment) or 70 000-80 000 (heat treatment). These results suggest that the transformation of androgen-receptor complexes from rat submandibular gland was induced by the subunit dissociation and that salt bridges may be involved in the subunit interaction.

Adenosine Triphosphate↗
PubMed1985

Membrane proteins in Rh+, Rh- and Rh: -29, 38 (- - -/- - -, rh) red cells compared by using SDS-polyacrylamide gel electrophoresis.

Since Rh: -29, 38 (- - -/- - -, rh) phenotype of the Rh blood groups (--- in text) revealed unusual red cells, such as stomatocytes and microspherocytes and the relatively shortened half life of 17 days, red cell membrane proteins from Rh + (D), Rh - (d) and --- were compared by using SDS-polyacrylamide gel electrophoresis (SDS-PAGE). No differences were observed among the patterns of the reduced and non-reduced membrane proteins from Rh+, Rh- and --- red cells. Two-dimensional gel electrophoresis of --- red cell membrane proteins also revealed a pattern similar to Rh+ and Rh- red cell membrane proteins. It is suggested that the lack of all Rh antigens causes no visible alteration of red cell membrane proteins detected by the method of Fairbanks G., Steck T.L. and Wallach D.F.H. (1971) Biochemistry, N.Y. 10, 2606-2617.

Electrophoresis, Polyacrylamide Gel↗
PubMed1985

The relationship of skin color, UVB-induced erythema, and melanogenesis.

The relationship between skin color, delayed erythema, and delayed tanning (DT) elicited by a single exposure of UVB was investigated. Both constitutive and facultative pigmentation were determined by skin reflectance using a melanometer. Skin reflectance using visible light was well correlated to the minimal immediate pigment darkening dose elicited by UVA irradiation, which may relate to epidermal melanin content, a determinant of skin color. Minimal erythemal dose (MED) was well correlated to skin color, but there was less correlation between minimal melanogenic dose and skin color or the MED, since melanogenesis is controlled by genetic factors. DT also correlated to the dose of UVB in terms of MED. A coefficient of the regression line of DT may suggest the tanning capacity of skin. The possibility of detecting mild photosensitivity in individuals from a regression line of the MED on skin color is suggested.

Erythema↗
PubMed1985

Intestinal absorption of ursodeoxycholic, glycoursodeoxycholic and tauroursodeoxycholic acids in rats.

We examined the intestinal absorption of ursodeoxycholic acid (UDC), glycoursodeoxycholic acid (GUDC) and tauroursodeoxycholic acid (TUDC) using an everted gut sac technique. UDC was absorbed throughout rat small intestine almost to the same extent. Absorption of both GUDC and TUDC, however, varied between jejunum and ileum. Absorption of these conjugated bile acids in the jejunal segments was less than that of UDC. While, absorption of GUDC and TUDC in the terminal ileum was more efficient than UDC. Although 2,4-dinitrophenol had no effect on the jejunal uptake, ileal uptake of these three bile acids was inhibited by 2,4-dinitrophenol.

Animals↗
PubMed1985

Demonstration and characterization of cytosol androgen receptor in rat exorbital lacrimal gland.

The presence of a macromolecule which binds androgen with a high affinity and a low capacity was demonstrated in the cytosol of the lacrimal glands of male and female rats. Evidence was found that this macromolecule was a protein by treatment with protease, trypsin or heat. A specific 8-8.5 S peak was obtained in both sexes by glycerol gradient centrifugation in low salt condition, whereas a specific 5.2 S peak was found in high salt condition. This protein could bind to DNA-cellulose after treatment of androgen-cytosol complexes by warming (25 degrees C 15 min) or exposure under high salt (0.4 M KCl). These results suggested that this protein was an androgen receptor.

Animals↗
PubMed1985

Dialysis-induced transformation of mouse submandibular androgen-receptor.

Dialysis induced transformation of cytosol androgen receptor from mouse submandibular gland. On DEAE-Sephacel chromatography, this dialyzed [3H]methyltrienolone receptor complex was eluted at 0.10 M KCl which was lower than 0.25 M KCl required to elute the nontransformed androgen receptor complex, but higher than 0.05 M KCl required to elute the heat transformed receptor. On glycerol density gradient centrifugation, the dialysis transformed receptor complex shifted its sedimentation coefficient to 6 S from 8 S of the nontransformed condition, whereas the heat transformed receptor was sedimented at 4 S. Molybdate inhibited the dialysis-induced transformation on DEAE-Sephacel chromatography. The charge and the molecular size of dialysis-induced transformed receptor complex were different from those of heat-induced transformed receptor complex.

Animals↗
PubMed1985

A rare suicidal case of a ten-year-old child stabbing himself in the throat.

A rare case is reported of a ten-year-old boy who committed suicide by stabbing himself in the throat with a pointed knife. Possibility of an accidental injury was excluded by the autopsy findings; suspicion of a homicide by his father was cleared through the deposition of his sister. The reason of suicide was attributed directly to his father's severe scolding and indirectly to his mother's death two years before.

Child↗
PubMed1985

Conversion from 4S androgen receptor from rat submandibular gland to higher molecular form and the effect of sodium molybdate.

The androgen receptor from rat submandibular gland was transformed by exposure to ATP at 0 degrees C. The transformed 4 S receptor converted to a higher molecular weight form in a low-salt glycerol gradient centrifugation when ATP was removed from the sample. The sedimentation coefficient of the converted receptor was similar in the absence or presence of 20 mM molybdate; 7.8 +/- 0.5 S without molybdate and 7.6 +/- 0.3 S with molybdate. However, the receptor converting in the presence of molybdate could markedly bind to DNA-cellulose, while an entity without molybdate could not. These results suggest that molybdate directly interacts with the DNA-binding domain on the 4 S androgen receptor and prevents this domain from being concealed by conversion in low-salt conditions.

Adenosine Triphosphate↗
PubMed1985

Effect of castration and administration of testosterone on cytosol and nuclear androgen receptor in mouse submandibular gland.

The effect of castration or administration of testosterone propionate on the subcellular distribution of androgen receptor in mouse submandibular gland was investigated. Within 10 h after castration of male mice, most of the androgen receptor in nuclei was significantly reduced, the androgen receptor in cytosol increased and the increased cytosol receptor retained for at least 40 h. A single injection of testosterone propionate to female mice resulted in the translocation of cytosol androgen receptor to the nuclei by 30 min. The nuclear receptor level remained for at least 24 h and the cytosol receptor was replenished by 24-72 h. These results reveal that the endocrine manipulations such as castration and testosterone injection cause the change in the subcellular distribution of androgen receptor from mouse submandibular gland in both sexes.

Animals↗