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Biomedical subjects

D Sutoo

Publications and source records attributed to D Sutoo.

45 records · Page 3Linked to original sources
PubMed1986

Divalent cation dependent conformations of brain calmodulin detected by 1H NMR.

The effects of the Ca2+, Mg2+, Zn2+, Cd2+, Hg2+ and Mn2+ on the conformation of calmodulin (CaM) have been tested by using 400 MHz 1H NMR. In the aromatic region of the spectrum of CaM with a one molar ratio of cation per CaM, Zn2+, Cd2+, Hg2+ and Mn2+ induced spectral changes which were very similar to those seen for Ca2+. However, the Mg2+-induced change was different. These results are consistent with our pharmacological findings on divalent cations.

Animals↗
PubMed1985

Effect of calmodulin antagonists on calcium and ethanol-induced sleeping time in mice.

This investigation was carried out to determine if calcium prolongation of ethanol-induced sleep is mediated by calmodulin and a calmodulin-dependent protein kinase. The duration of ethanol-induced sleeping time in ddY male mice was measured following the administration of CaCl2 (20, 40, 80 and 200 mumol/kg, intraperitoneally (IP) both with and without the calmodulin antagonists, W-7: [N-(6-Aminohexyl)-5-chloro-1-naphthalenesulfonamide] (4.2 micrograms/mouse, intraventricular (IVT) or trifluoperazine (TFP; 1.8 micrograms/mouse, IVT). When CaCl2 was administered in a dose dependent manner the duration of ethanol-induced sleep was prolonged. The prolongation was antagonized by W-7 and TFP. When mice were treated with W-7 or TFP together with serotonin (5-HT; 15 nmol/mouse, IVT), dopamine (DA; 30 nmol/mouse, IVT) or norepinephrine (NE; 30 nmol/mouse, IVT), the sleeping time induced by ethanol and calcium was enhanced. This finding suggests that W-7 and TFP selectively inhibit the synthesis of 5-HT, DA and NE, but they do not affect other neuronal functions of these biogenic amines. The results would suggest a probable mechanism in which Ca++ prolongs ethanol-induced sleeping time by activating tyrosine hydroxylase and tryptophan hydroxylase through intracerebral calmodulin and calmodulin-dependent protein kinase, which subsequently raise the levels of 5-HT, DA and NE.

Animals↗
PubMed1983

Immunohistochemical identification of cholinergic cells in non-cloned tumor cells.

The objective of this investigation was to characterize non-cloned neuroblastoma cells immunohistochemically. In this study, the cholinergic cells in three mouse tumors were identified by using a choline acetyltransferase (CAT) antibody. Different cholinergic cell distribution patterns were found in the three tumors by using a fluorescence-activated cell sorter (FACS). An antibody to CAT was prepared by immunization of guinea pigs with CAT-antigen from bovine brain. The specificity of the antibody obtained was examined with mouse cervical spinal cord. Identification of the cholinergic cells was performed in three types of non-cloned tumor culture cells, neuroblastoma C-1300 in A/J mice, glioblastoma 203GL in C57BL6 mice and lymphosarcoma 6C3HED in CBA mice. The CAT content and distribution were determined by radiochemical assay, immunohistochemical staining, and individual cell counting with a FACS. The results of radiochemical assay and immunohistochemical staining were in agreement with the CAT distribution pattern determined by cell counting with FACS IV.

Animals↗
PubMed1981

Decrease of a peptide in the cat spinal cord after upper cervical transection.

The effects of a transection on the peptide contents in the cat cervical spinal cord have been investigated. Seven days following the hemisection at the C1 level, the C5-8 levels of the spinal cord were used for the biochemical analyses. A crude peptide extract was fractionated on a Sephadex G-15 column. The third major peak which contained smaller molecular weight peptides was collected and separated with a peptide map on the cellulose TLC plate. Three ninhydrin-positive and two ninhydrin-negative peptides were found on the TLC plate. When we compared between the operated side and the control side, a ninhydrin-negative peptide, whose acid hydrolysate was composed of glutamic acid and aspartic acid in a ratio of 1:2, was decreased by approximately 30% in the operated side of the spinal cord.

Animals↗
PubMed1981

[Immunohistochemical analysis of tumor cells using choline acetyltransferase (author's transl)].

For an immunohistochemical analysis of cellular function of tumors, as related to acetylcholine, the antibody to choline acetyltransferase from bovine brain was obtained in guinea pigs. The specificity of the antibody was immunohistochemically studied in the cervical spinal cord of the mouse. And the findings coincided well with the biochemically and histochemically data on the distribution of choline acetyltransferase or acetylcholinesterase in the spinal cord. The choline acetyltransferase activity in the tumor cells at 6-10 days after subculture was 2.26 nmol/1 x 10(5) cells/hr in glioblastoma, 1.77 nmol/1 x 10(5) cells/hr in C-1300 and 1.45 nmol/1 x 10(5) cells/hr in sarcoma and the difference was statistical. In the immunohistochemical cell staining of these tumors, the rate of fluorescence-positive cells was 82.0% in glioblastoma, 37.3% in C-1300 and 4.2% in sarcoma. These findings coincide well with data on the enzymatic activity. The antibody is applicable not only in the field of the immunohistochemistry, but also for a mechanical analysis of cells at the single cell level, as demonstrated by Fluorescence Activated Cell Sorter (FACS).

Animals↗
PubMed1979

Effect of transection on choline acetyltransferase, thyrotropin releasing hormone and substance P in the cat cervical cord.

The effects of a transection on the choline acetyltransferase activity, the thyrotropin releasing hormone and substance P contents in the cat cervical spinal cord have been investigated. Seven days after the hemitransection at the C1 level, the grey matter of the C6-7 levels of the spinal cord were dissected for the biochemical measurements. The choline acetyltransferase activity and the thyrotropin releasing hormone content remained unchanged in any regions in the grey matter following the high cervical transection. On the other hand, the substance P content was decreased by approx. 70% in the ventral horn. These results suggest that the fibers originating the supraspinal structures and terminating in the grey matter of the spinal cord, contain the substance P-releasing fibers, whereas there seems to be little cholinergic or thyrotropin releasing hormone-containing fibers.

Acetyltransferases↗
PubMedDate not supplied

Modulating effects of biogenic amines on calcium and ethanol-induced sleeping time.

The present study was carried out in order to clarify the mechanism of calcium prolongation of ethanol-induced sleep. p-Chlorophenylalanine (PCPA, 300 mg/kg), alpha-methyltyrosine (alpha MPT, 100 mg/kg) and diethyldithiocarbamate (DDC, 250 mg/kg) were administered intraperitoneally (IP) to mice to reduce the levels of serotonin (5-HT), dopamine (DA) and norepinephrine (NE) respectively in the brain. Sleeping time was then measured following the administration of ethanol (4.5 g/kg, IP) both with and without CaCl2 (20 mumol/kg, intravenous (IV)). When saline (IP) plus CaCl2 (IV) was administered, the duration of ethanol-induced sleep was prolonged by 100% as compared with saline (IP) plus saline (IV). Duration of ethanol-induced sleep was not changed by PCPA, alpha MPT and DDC. On the other hand, the prolongation of ethanol-induced sleep by CaCl2 was antagonized by PCPA, alpha MPT and DDC. Also, only the DA level in the cerebrum was increased by 25% by administration of CaCl2. We suggest that the increase in ethanol-induced sleeping time due to CaCl2 results from the increase in biogenic amines in the brain.

Animals↗
PubMedDate not supplied

The ability of divalent cations to enhance ethanol-induced sleeping time.

This investigation was carried out to determine if prolongation of ethanol-induced sleep by divalent cations is mediated by calmodulin (CaM) and biogenic amine. The effects of CaM antagonist, W-7:[N-(6-Aminohexyl)-5-chloro-1-naphthalenesulfonamide], serotonin (5-HT) synthesizing enzyme inhibitor, p-chlorophenylalanine (PCPA), and catecholamine synthesizing enzyme inhibitor, alpha-methyltyrosine (alpha MPT) on ethanol-induced sleeping time enhanced by divalent cations were studied in ddY male mice. The ethanol-induced sleeping time was increased by 70, 200, 180, 70, and 45% by intraventricular (IVT) injection of CaCl2 (10 mumol/kg), MnCl2 (15 mumol/kg), ZnCl2 (2.5 mumol/kg), CdCl2 (1 mumol/kg), and HgCl2 (1 mumol/kg), respectively, compared to the saline group. On the other hand, when mice were treated IVT with W-7 and their divalent cation, the sleeping time induced by ethanol was decreased compared to that of the cation without W-7 treated mice. Also, when mice were injected simultaneously with either PCPA or alpha MPT and CaCl2, ZnCl2, CdCl2, or HgCl2, the ethanol-induced sleeping time was less compared to those given saline together with their cation, respectively. These results would suggest a probable mechanism in which Ca++, Zn++, Cd++, and Hg++ prolong ethanol-induced sleeping time by activating biogenic amine synthesizing enzymes through cerebral CaM and CaM-dependent protein kinase.

Alcohol Dehydrogenase↗