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Biomedical subjects

F Nakagawa

Publications and source records attributed to F Nakagawa.

At least 37 records · Page 2Linked to original sources
PubMed1989

Sex difference of the metabolic disposition of clioquinol in rats.

The order of plasma levels of clioquinol and its conjugates in male rats after intraduodenal administration of 32.7 mumol/kg dose of clioquinol was clioquinol sulfate (C-Sul) greater than glucuronide (C-Glu) much greater than clioquinol, whereas that in female rats was C-Glu greater than C-Sul much greater than clioquinol. Total (urine + bile) recovery was almost the same among male and female rats. The percentage of excretion amounts of C-Sul (urine + bile) to the total excretion amounts for 24 h in male rats after intravenous administration of clioquinol was about twice that in female rats, while the percentage of excretion amounts of C-Glu to the total excretion amounts in male rats was smaller than that in female rats. In intravenous administration of 16.4 mumol/kg dose of C-Glu, C-Sul and clioquinol other than C-Glu were found in bile and urine of male and female rats. The percentage of excretion amounts of C-Sul and C-Glu (urine + bile) to the total excretion amounts was similar among male and female rats, respectively. In intravenous administration of 16.4 mumol/kg dose of C-Sul, C-Glu and clioquinol other than C-Sul were found in bile and urine of male and female rats, and the percentage of excretion amounts of C-Sul (urine + bile) to the total excretion amounts in male rats was 1.3 fold that in female rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Determination of ambenonium in biological samples by reversed-phase ion-pair liquid chromatography.

A sensitive and selective analytical method for the determination of ambenonium ion in biological samples is described. The procedure involves ion-pair extraction of the drug, followed by reversed-phase ion-pair chromatographic analysis with ultraviolet detection at 217 nm. The detection limits at a signal-to-noise ratio of 5 were 100 pmol/ml using 0.2 ml of plasma and bile, 250 pmol/ml using 0.2 ml of urine and 200 pmol/g using 1 ml of tissue homogenates containing 0.1 g/ml of each tissue. This assay procedure was used to study the pharmacokinetics of ambenonium ion after intravenous administration in rats.

Ambenonium Chloride↗
PubMed1988

Determination of pemoline in plasma, urine and tissues by reversed-phase high-performance liquid chromatography.

A simple and selective high-performance liquid chromatographic method with ultraviolet detection at 215 nm for the determination for pemoline in rat plasma, urine and tissues is described. Pemoline in the samples was extracted with methylene chloride at pH 10 and the organic phase was evaporated after adding 5-methyl-5-phenylhydantoin used as an internal standard. Pemoline and the internal standard were separated on a Kaseisorb LC C8-60-5 reversed-phase column. The limits of determination of pemoline in 0.1-0.2 ml of plasma, urine and tissue homogenates were 2, 100 and 20 ng, respectively. The method should be useful for studies of the pharmacokinetics and distribution of pemoline in small animals.

Animals↗
PubMed1988

Changes in lipid peroxide concentrations in plasma and tissues by repeated administration of clioquinol to neonatal rats.

The changes in lipid peroxide concentrations in plasma and tissues after subcutaneous administration of clioquinol to clioquinol-sensitive (S-rats) and -resistant neonatal rats (R-rats) were investigated. When a fixed dose of 150 mg/kg/d of clioquinol was given to R-rats for 14 d after birth, no significant difference in lipid peroxide concentrations in plasma, liver, kidney, brain and spinal cord at 5, 10 and 15 d was observed between clioquinol-treated and untreated rats. However, with increasing doses of clioquinol to R-rats every 5 d (150----300----600 mg/kg/d), the lipid peroxide concentrations at 15 d were higher in plasma, brain and spinal cord of clioquinol-treated rats than in those of untreated rats. These results suggested that repeated administrations of large doses of clioquinol to rats increased the lipid peroxides in nerve tissues. With S-rats at 5 d after birth, the lipid peroxide concentrations in liver were approximately twice those in R-rats regardless of the clioquinol administration.

Animals↗
PubMed1987

Postnatal appearance of glycoconjugate with terminal N-acetylgalactosamine on the surface of selected neurons in mouse brain.

Selected neurons in the cortex and other regions of the brain of adult mice stain with Vicia villosa agglutinin (VVA) conjugated to horseradish peroxidase (HRP). This staining demonstrates glycoconjugate with terminal N-acetylgalactosamine (GalNAc) in periodic foci on the neuronal surface. However, brains from mice at 1 week of age lacked neurons with surface reactivity for VVA-HRP but showed neurons with faint cytoplasmic staining. Two weeks postnatally, infrequent cortical neurons located mostly in layer IV disclosed light surface affinity for VVA-HRP. The deep cerebellar nucleus at 2 weeks revealed VVA-positive neurons that were less abundant than in adults but exceeded in number the stained neurons in the cortex of 2-week-old mice. By 3 weeks of age the prevalence of positive neurons in cortical layers II-VI and the deep cerebellar nucleus and the intensity of the surface staining approximated that observed in adult mice. No staining of fiber tracts was observed 1 week postnatally. However, certain tracts exemplified by decussating fibers in the basal pontine region showed strong VVA-HRP reactivity in brains of 2-week-old mice as in adults. Acquisition of VVA surface affinity 3 weeks postnatally coincided with the appearance of cytosolic immunostaining for glutamic acid decarboxylase in a population of GABAergic neurons in the cortex. These findings demonstrate the postnatal development of GalNAc-containing glycoconjugate associated with selected neurons and the variable acquisition of the glycoconjugate among these neurons possibly related to onset of function.

Acetylgalactosamine↗
PubMed1986

Selective cytochemical demonstration of glycoconjugate-containing terminal N-acetylgalactosamine on some brain neurons.

Paraffin embedded sections of rat, mouse, dog, and human brain were stained with a battery of lectin-horseradish perioxidase conjugates to localize and characterize glycoconjugates. In the rat and mouse cerebral cortex, a subpopulation of nonpyramidal neurons stained selectively with three lectins with specific affinity for terminal N-acetylgalactosamine (GalNAc). These and only these lectins stained the surface of the cell body, dendritic shafts, and proximal parts of the dendritic arborization. Most reactive, nonpyramidal neurons revealed a multipolar dendritic pattern, but some possibly belonged to the bitufted and bipolar types of neuron. The GalNAc-containing neurons appeared widely distributed in layers II-VI with relatively greater abundance in layers IV and V. In the cortex of rats and mice the stained neurons occurred in moderate numbers in the frontal, frontoparietal, striate, retrosplenial, and entorhinal regions, but were less numerous in the hippocampal gyrus, dentate gyrus, and olfactory area. Other neurons in the basal ganglia and brain stem stained weakly for GalNAc. Examination of the frontal cortex of human and canine brains showed a similar distribution of nonpyramidal neurons with affinity for GalNAc-binding lectins. At high magnification, the surface staining of neurons in the cerebral cortex, deep cerebellar nucleus, and other sites appeared periodic rather than continuous. The periodic character of the neuronal surface staining suggested a location for the reactive glycoconjugate in or between the synapses. The GalNAc-containing glycoconjugate occurred in a selected cell type, failed to bind the other lectin conjugates, and differed from biochemically detected glycoconjugates. It is, therefore, considered a newly recognized entity of possible physiologic significance for a population of cortical neurons.

Acetylgalactosamine↗
PubMed1986

Lectin cytochemical evaluation of somatosensory neurons and their peripheral and central processes in rat and man.

Paraffin sections of the trigeminal nerve root of the rat, and human spinal nerve root and trigeminal ganglion were stained with a battery of lectin-horseradish peroxidase conjugates to localize and characterize glycoconjugate (GC) in situ. In the rat the myelin sheath of the peripheral segment contained GC with sialic acid most probably linked to the penultinate disaccharide galactose-(beta 1----4)-N-acetylglucosamine (Gal(beta 1----)-GlcNAc), and complex type N-glycosidic side chains. The myelin sheath in the central segment differed in containing little if any of the GC named above and in containing GC with terminal beta-Gal linked to N-acetylgalactosamine (GalNAc), terminal GalNAc and fucose. Schwann cells stained for GC with GlcNAc or mannose whereas oligodendroglia stained for GC with the terminal disaccharide Gal-(beta 1----3)-GalNAc and N-glycosidic side chains, especially in presumed Golgi zones, but also in processes continued as the outer myelin sheath. The human myelin sheath in the central segment differed from that of the rat in not staining with lectins specific for fucose and terminal GalNAc. Sialic acid and terminal beta-Gal were seen in the human central segment but these sugars appeared to bind to astroglial structures rather than to the myelin sheath as in the rat. Astrocytes in both rat and man were stained by two fucose-binding lectins. Several lectins revealed affinity for GC in the neurilemmal sheath, and staining of this structure was stronger in the human specimens. Neurons in the human trigeminal ganglion ranged from unstained to strongly positive for fucoconjugate in cytoplasmic bodies and plasmalemma. Positive ganglion cells gave rise to unmyelinated fibers which also stained for fucoconjugate. Remak fibers and their extensions into the substantia gelatinosa of the human spinal cord stained strongly for content of fucose. The stronger lectin affinity for N-glycosidic core sugars in the peripheral as compared with the central segment suggests that lectins localize Po protein in peripheral myelin. The reactivity for several sugars in the central segment can possibly be attributed to myelin-associated glycoprotein (MAG) of central myelin, but lectin staining for GalNAc shows in addition a biochemically unrecognized GC with O-glycosidic linked oligosaccharides in myelin. The lectin cytochemistry indicates that the 170 K Dalton glycoprotein with PNA affinity obtained from rat sciatic nerves occurs in nodes of Ranvier.

Adult↗
PubMed1986

Lectin cytochemistry of cell types in human and canine pituitary.

Labeled lectins specific for different sugars were employed to identify different cell types in pituitaries from six human autopsies and seven dogs. To determine the lectins bound by each cell type, fixed-paraffin embedded sections serial to those stained with lectins were immunostained for specific hormones and the serial pairs were examined in a comparison microscope. In human pituitaries corticotrophs stained selectively with lectins having affinity for alpha-L-fucose and the core region of complex type N-glycosyl-proteins. Some corticotrophs also stained for the presence of terminal beta-galactose. Thyrotrophs stained selectively with a periodate oxidation-borohydride reduction-concanavalin A sequence. Some mammotrophs evidenced content of glycoconjugate with terminal beta-galactose. Dendritic cells stained selectively for abundant glycogen with the periodate-reduction-concanavalin A sequence and a lectin from Griffonia simplicifolia. Adenohypophyseal cells of dog pituitary differed in showing absence of terminal beta-galactose in corticotrophs, presence of terminal beta-galactose in thyrotrophs, presence of glycoconjugate with N-glycosidically bound oligosaccharide in thyrotrophs and gonadotrophs and presence of terminal beta-galactose with a different lectin affinity in mammotrophs. The main contributions of lectin histochemistry applied to the pituitary include providing an additional histologic method for identification of some cell types, and localizing glycosylated prohormone or other biochemically unrecognized non-hormone glycoconjugates whose function in pituitary cells remains to be explained.

Adult↗
PubMed1986

The immunocytochemical demonstration of copper-zinc superoxide dismutase in the brain.

Copper-zinc superoxide dismutase (CuZn-SOD) has been localized in formalin-fixed, paraffin-embedded sections of both canine and rat brains. Staining with an immunoenzyme bridge sequence revealed CuZn-SOD in all regions of the brains examined. Specific sites of localization included cerebral cortical pyramidal cells, cerebellar Purkinje cells, neurons in 'subcortical nuclei', and oligodendrocytes throughout the brain. Similar sites of CuZn-SOD localization were identified in both species. These results are compared with reports by various investigators of SOD bioactivity in the brain.

Animals↗