Effects of chronic bifemelane hydrochloride administration on receptors for N-methyl-d-aspartate in the aged-rat brain

We assayed N-methyl-d-aspartate (NMDA) receptors [³H]3-(2-carboxypiperazin-4-yl)propyl-1-phosphonic acid ([³H]CPP) bindings) and evaluated their distribution in the brain by quantitative autoradiography in young adult and aged rats. In the young adult rats, NMDA receptors were present at relatively high concentrations in the cerebral cortex and hippocampus. In the aged rats, NMDA receptors were decreased in the nealy all areas of the brain, especially in the cerebral cortex and hippocampus. Chronic administration of bifemelane hydrochloride, a drug for sequela of cerebrovascular diseased, at a dose of 15 mg/kg/day for 14 days, markedly attenuated these decrease in NMDA receptors. Since NMDA receptors are considered to be involved in memory and learning processes, our results suggest that bifemelane hydrochloride may be applicable to the treatment of disturbed memory and learning.     

Manganese-histidine cluster as the functional center of the water oxidation complex in photosynthesis

The recent model of Kambara and Govindjee for water oxidation [Kambara T. and Govindjee (1985) Proc. Natl. Acad. Sci. U.S.A., 82:6119–6123] has been extended in this paper by examining all the data in order to identify the most likely candidate for the redox-active ligand (RAL), suggested to operate between the water oxidizing complex (WOC) and Z, the electron donor to the reaction center P680. We have concluded that a very suitable candidate for RAL is the imidazole moiety of a histidine residue. The electrochemical data available on imidazole derivatives play heavily in this identification of RAL. Thus, we suggest that histidine might play the role of an electron mediator between the WOC and Z. A model of S-states in terms of their plausible chemical identity is presented here.Abbreviations J electronic spin of ion - P680 reaction center chlorophyll - RAL Redox active ligand - S_n state of the oxygen-evolving system - WOC water oxidation complex - Z electron donor to P680 Dedicated to Prof. L.N.M. Duysens on the occasion of his retirement     

Increased choline acetyltransferase activity by Chinese herbal medicine Sho-saiko-to-go-keishi-ka-shakuyaku-to in aged rat brain

The effect of a Chinese herbal medicine Sho-saiko-to-go-keishi-ka-shakuyaku-to (TJ-960) on the brain choline acetyltransferase (CAT) activity was studied in adult (3.5 months of age) and aged (24 months of age) rats. After oral administration of 5% TJ-960 solution for 3 months, CAT activity in the hippocampus, pons-medulla oblongata and striatum of aged rats was significantly lower than that of adult rats. CAT activity in the cerebellum, however, was significantly higher in the aged rats, as compared to the adult rats. TJ-960 significantly increased CAT activity in the hippocampus and striatum of aged rats, but did not affect the activity of the enzyme in the adult rat brain.     

Primary structure of guinea-pig Hageman factor: sequence around the cleavage site differs from the human molecule.

The guinea-pig and human Hageman factors differ in their sensitivity to activation by particular bacterial proteinases. To understand this difference, the primary structure and cleavage site on activation of the guinea-pig molecule were determined and compared with the human molecule. By the use of a synthetic oligodeoxyribonucleotide probe which encoded a part of human Hageman factor cDNA, a cDNA clone was isolated from a lambda gt11 cDNA library of guinea-pig liver and sequenced. The cDNA clone was identified as that of guinea-pig Hageman factor by the complete identity of the deduced amino-acid sequence with the actual sequence of the amino-terminal portion of guinea-pig Hageman factor molecule and the active form. The cDNA included part of a leader sequence and the entire coding region of the Hageman factor molecule. Guinea-pig Hageman factor was composed of the same domain structures as the human counterpart with an overall 72% homology in the amino-acid sequence. However, the sequences around the cleavage site were surprisingly different; -Met351-Thr-Arg-Val-Val-Gly-Gly-Leu-Val359-(human) and -Leu338-Ser-Arg-Ile-Val-Gly-Gly-Leu-Val346-(guinea-pig). The amino-acid substitutions around the cleavage site might explain the difference in sensitivity to activation between the human and guinea-pig molecules.     

Isolation and identification of (2S)-2-amino-5-chloro-4-hydroxy-5-hexenoic acid from anAmanita of the sectionRoanokenses (Amanitaceae)

A chlorine-containing non-protein amino acid which was recently discovered from the fruit bodies ofAmanita gymnopus (2S)-2-amino-5-chloro-4-hydroxy-5-hexenoic acid, was isolated and crystallized for the first time from the fruit bodies of an unknown member ofAmanita belonging to the sectionRoanokenses, subsectionSolitariae. The results of elementary analyses, determination of optical rotations,¹H- and¹³C-NMR-spectra, and some chemical reactions supported an earlier proposed structure.Part 24 in the series Biochemical studies of nitrogen compounds in fungi. for Part 23, see Hatanaka, S. I. et al. 1994. this journal35: 391–394.     

A Serine Protease in Soybean Seeds That Acts Specifically on the Native {alpha} Subunit of {beta}-Conglycinin

A proteolytic activity directed against the     

Newly established cell lines fromDrosophila larval CNS express neural specific characteristics

Summary From the central nervous system ofDrosophila melanogaster 3rd instar larvae, eight continuous cell lines have been established (named ML-DmBG1 to 8). Using ML-DmBG2, single colony isolation was carried out and six colonial clones were obtained. All reacted to the antibody to horseradish peroxidase, which is a neuronal marker in insects. Acetylcholine, a known neurotransmitter inDrosophila, was detected in three of the colonial clones by high performance liquid chromatography. Therefore, it is concluded that the established colonial clones are neural cells originating in the larval central nervous system. Among them, some variation was observed with respect to morphology, acetylcholine content, and reactivity to anti-HRP. The variation may reflect the heterogeneity of cells composing the central nervous system.     

Construction of integrated system for selection of fused plant protoplasts

Summary An integrated system has been constructed to instantly identify and efficiently sort the heterokaryons formed by plant protoplast fusion. The system is composed of the following functions: a) a transport system, b) an electro-manipulator, c) a cell harvester, d) a flow cytometer/cell sorter, and e) a control device. The conditions for an efficient and reproducible enrichment of the heterokaryons have been investigated by this system using the fluorescein isothiocyanate stained protoplasts preparing from Glycyrrhiza glabra cell cultures and unstained protoplasts of Abrus precatorius cell cultures which contain a large quantity of chlorophyll.Abbreviations MS Murashige and Skoog (1962) - 2,4-D 2, 4-dichlorophenoxyacetic acid - NAA 1-naphthaleneacetic acid - BAP 6-benzylaminopurine - ABA abscissic acid - FITC fluorescein isothiocyanate This paper is part 96 in the series Studies on Plant Tissue Cultures. For part 95 see Orinara Y., Noguchi T. and Furuya T. (1993) submitted for publication.     

A method of the selective isolation and enumeration of marine Vibrionaceae

A noninhibitory medium and GasPack anaerobic culture system were employed for the selective enumeration and isolation of Vibrionaceae in seawater and marine sediments.Vibrio counts obtained by the new method for seawater and sediment samples were compared with vibrio numbers in the heterotrophic bacterial population appearing on a medium routinely employed in the laboratory for such counts. The ratio of the former to the latter counts ranged from 0.5 to 1.3, the average being 0.96. The seawater and sediment bacteria that grew and produced visible colonies on the medium under anaerobic conditions for 3 days at 20°C were almost exclusively vibrios.From the results reported here it is concluded that most of the vibrios present in seawater and sediment samples can be recovered by the new method developed in this study.