Neuron-immune interactions in the sensitized thalamus induced by mustard oil application to rat molar pulp.

We have reported that mustard oil application to the rat dental pulp induces neuronal activation in the thalamus. To address the mechanisms involved in the thalamic changes, we performed neuronal responsiveness recording, immunohistochemistry, and molecular biological analysis. After mustard oil application, neuronal responsiveness was increased in the mediodorsal nucleus. When MK801 (an N-methyl-D-aspartate receptor antagonist) was applied to the mediodorsal nucleus, the enhanced responsiveness was decreased. N-methyl-D-aspartate receptor 2D, glial fibrillary acidic protein, and antigen-presenting cell-related gene mRNAs in the contralateral thalamus were up-regulated at 10 minutes after mustard oil application, but were down-regulated within 10 minutes after the antagonist application. OX6-expressing microglia and glial fibrillary acidic protein-expressing astrocytes did not increase until 60 minutes after mustard oil application. These results suggested that the thalamic neurons play some roles in regulating the glial cell activation in the mediodorsal nucleus via N-methyl-D-aspartate receptor 2D during pulp inflammation-induced central sensitization.

Aspectos étnicos, biológicos e químicos de Senna occidentalis (Fabaceae) / Ethnic, biological and chemical aspects of Senna occidentalis (Fabaceae)

Senna occidentalis (sin. Cassia occidentalis) é um arbusto perene nativo da América do Sul e distribuída em regiões tropicais ao redor do mundo, frequentemente contaminando pastos e culturas de cereais. Inúmeros estudos demonstraram que esta planta é tóxica para animais. Na medicina popular, tribos americanas, africanas e indianas usam preparações da S. occidentalis como tônico, estomáquico, febrífugo, laxante e antimicrobiano. Diversas propriedades biológicas da espécie já foram comprovadas, tais como a antibacteriana, antifúngica, antimalárica, antitumoral e hepatoprotetora. As análises fitoquímicas evidenciaram que as antraquinonas, os flavonóides e outros derivados fenólicos são os seus principais constituintes. Esta revisão apresenta dados etnofarmacológicos, químicos e biológicos publicados na literatura sobre S. occidentalis.

Senna occidentalis (syn. Cassia occidentalis) is a perennial shrub, native to South America and indigenous to tropical regions throughout the world, often contaminating pastures and cereal crops. There have been many reports showing that S. occidentalis is toxic to animals. In traditional medicine, some American, African and Indian ethnic groups use S. occidentalis preparations in stomach treatments and as a tonic, febrifuge, laxative and topical antimicrobial agent. Several biological properties of this species have been proved, such as antibacterial, antifungal, antimalarial, antitumor and hepatoprotective activity. Phytochemical analysis has shown that anthraquinones, flavonols and other phenolics are its major constituents. In this paper we present an overview of the ethnopharmacological, chemical and biological data published in the literature on S. occidentalis.

Inhibition of azoxymethane-induced aberrant crypt foci formation in rat colorectum by whole leaf Aloe arborescens Miller var. natalensis Berger.

We examined the modifying effect of whole-leaf Aloe arborescens Miller var. natalensis Berger (designated as 'ALOE') on azoxymethane (AOM)-induced aberrant crypt foci (ACF), putative preneoplastic lesions, in the rat colorectum. Male F344 rats (4 weeks old) were fed the basal diet, or experimental diets containing 1% or 5% ALOE for 5 weeks. One week later, all rats except those in the vehicle-treated groups were injected s.c. with AOM (15 mg/kg, once weekly for 3 weeks). At 9 weeks of age, all the rats were killed, and the colorectum and liver were evaluated for ACF and cytosolic quinone reductase (QR; a phase 2 enzyme), respectively. In rats given AOM and ALOE (1% or 5% in diet) the numbers of ACF/colorectum, aberrant crypts/colorectum, aberrant crypts/focus and large ACF/colorectum were significantly decreased compared with those of rats given AOM alone (all p < 0.01). No ACF were found in rats treated without AOM. In addition, ALOE significantly increased cytosolic QR activity in the liver (p < 0.01). These results indicated that ALOE inhibited the development of AOM-induced ACF in the rat colorectum, with increased QR activity in the liver, and therefore suggested that ALOE might have a chemopreventive effect against colon carcinogenesis at least in the initiation stage.

Protein kinase C gamma-like immunoreactivity of trigeminothalamic neurons in the medullary dorsal horn of the rat.

We examined protein kinase C gamma-like immunoreactivity (PKCgamma-LI) of trigeminothalamic neurons in the rat medullary dorsal horn (MDH) after injecting a retrograde tracer, Fluoro-Gold (FG), into the thalamus. Over 90% of FG-labeled neurons in the marginal layer (lamina I) and a few FG-labeled neurons in the superficial part of the magnocellular layer (lamina III) showed PKCgamma-LI. No PKCgamma-neurons in the substantia gelatinosa (lamina II) were labeled with FG. PKCgamma-mediated regulation of trigeminothalamic neurons may contribute to the changes in MDH activity during persistent pain.

Screening of Chinese herbal drug extracts for inhibitory activity on nitric oxide production and identification of an active compound of Zanthoxylum bungeanum.

Sixty-eight water and methanol extracts from 34 Chinese herbal drugs, most of which are used for inflammatory diseases, were screened for their inhibitory effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated J774.1 macrophages and in LPS/interferon (IFN)-gamma-stimulated mouse peritoneal exudate macrophages. Among the extracts, methanol extracts of Myristica fragrans, Plantago asiatica, Rubia cordifolia, and Zanthoxylum bungeanum showed significant inhibition in J774.1 macrophages, while in mouse peritoneal exudate macrophages, water extracts of Ru. cordifolia and Scutellaria baicalensis and methanol extracts of Angelica megaphylla, My. fragrans, and Z. bungeanum inhibited the NO production. Among them, inhibition of water extract of Sc. baicalensis was found to be mainly due to direct scavenging of NO radicals, through an examination of its scavenging activity on PAPA NONOate-generated NO radicals, while water extract of Ru. cordifolia and methanol extracts of An. megaphylla, My. fragrans, P. asiatica, and Z. bungeanum showed inhibition on iNOS mRNA expression. At last, an inhibitory compound on iNOS mRNA expression was isolated from a methanol extract of Z. bungeanum and identified as 4-O-beta-D-glucopyranosyldihydroferulic acid by NMR spectral analyses and chemical synthesis.

Water-diluted local anesthetic for trigger-point injection in chronic myofascial pain syndrome: evaluation of types of local anesthetic and concentrations in water.

BACKGROUND AND OBJECTIVES: We have recently demonstrated that a mixture of 1% lidocaine with water in a 1:3 ratio has less injection pain and is more effective than unaltered 1% lidocaine in treating chronic myofascial pain syndromes. Yet, the most suitable local anesthetic and the most effective dilution in water have not been evaluated. METHODS: Various mixtures of local anesthetics and water or saline were injected intramuscularly into the shoulder of 40 female volunteers, and pain scores on injection were evaluated in a randomized and double-blinded manner. In another portion of the study, 0.25% or 0.2% lidocaine in water were injected randomly into 1 side of 21 outpatients with chronic neck, shoulder, or lumbar myofascial pain to the same degree in both sides. The other solution was injected into the other side of the same patients. RESULTS: Less injection pain was experienced with the water-diluted 0.25% lidocaine and water-diluted 0.25% mepivacaine than the saline-diluted 0.25% lidocaine and water-diluted 0.0625% bupivacaine. Also, less injection pain was experienced with the water-diluted 0.25% and 0.2% lidocaine than the water-diluted 0.3% and 0.15% lidocaine. In the other study, there were no differences in either the effectiveness or duration of analgesia between the 0.25% and 0.2% water-diluted lidocaine. CONCLUSIONS: The suitable type of local anesthetic may be lidocaine or mepivacaine, and the most effective water-diluted concentration is considered to be 0.2% to 0.25%.

Immunocytochemical localization of candidates for vesicular glutamate transporters in the rat cerebral cortex.

Brain-specific Na(+)-dependent inorganic phosphate cotransporter (BNPI) was recently reported to serve as a vesicular glutamate transporter (VGluT), and was renamed VGluT1 (Bellocchio et al. [ 2000] Science 289:957-960; Takamori et al. [2000] Nature 407:189-194). Ahead of these reports, cDNA encoding another brain-specific inorganic phosphate transporter, which showed 82% amino acid identity to VGluT1, was cloned and designated differentiation-associated Na(+)-dependent inorganic phosphate cotransporter (DNPI; Aihara et al. [2000] J Neurochem 74:2622-2625). In the present study, we produced a specific antibody against a C-terminal portion of DNPI, and studied the immunohistochemical localization of DNPI in the rat cerebral cortex in comparison with that of VGluT1. DNPI immunoreactivity was enriched in neuropil of layers I and IV and to a lesser extent in the upper portion of layer VI of the cerebral neocortex, whereas VGluT1 immunoreactivity was distributed more evenly in neuropil of the neocortex. Electron microscopic observation revealed that both DNPI and VGluT1 immunoreactivities were mainly located on synaptic vesicles in nerve terminals which made asymmetrical contacts in the neocortex. Furthermore, neither DNPI nor VGluT1 immunoreactivity in the neocortex was colocalized with gamma aminobutyric acid (GABA)ergic axon terminal markers, immunoreactivity for glutamic acid decarboxylase or vesicular GABA transporter. Neuronal depletion in the ventrobasal thalamic nuclei produced by the kainic acid injection resulted in a clear reduction of DNPI immunoreactivity in layers I, IV, and VI of the somatosensory cortex. These results indicate that DNPI is located on the membrane of synaptic vesicles in thalamocortical axon terminals, and that it may be a candidate for VGluT of thalamocortical glutamatergic neurons.

Synthesis and evaluation of novel 2-oxo-1,2-dihydro-3-quinolinecarboxamide derivatives as potent and selective serotonin 5-HT4 receptor agonists.

A series of 8'-substituted N-(endo-8-azabicyclo[3.2.1]oct-3-yl)-1-isopropyl-2-oxo-1,2-dihydro-3-quinolinecarboxamides were synthesized. The 5-HT4 receptor agonistic activity was evaluated using the isolated guinea pig ileum preparation. Of the compounds synthesized, N-(endo-8-(3-hydroxypropyl)-8-azabicyclo[3.2.1]oct-3-yl)-1-isopropyl-2-oxo-1,2-dihydro-3-quinolinecarboxamide (15a, TS-951) exhibited the most potent serotonin 5-HT4 receptor agonistic activity. This compound had a high affinity for the serotonin 5-HT4 receptor although it had no affinities for other broad spectrum receptors. Furthermore, it remarkably enhanced gastrointestinal motility in conscious fed dogs without unfavorable effects that non-selective serotonin 5-HT4 receptor agonist has. TS-951 may be useful in improving gastrointestinal dysfunction.

[Effects of nilvadipine on retinal microcirculation and systemic circulation].

PURPOSE: The effects of nilvadipine on retinal blood flow and systemic circulation were studied by the hydrogen clearance method. MATERIALS AND METHODS: The subjects were 10 male beagles. Under general anesthesia, nilvadipine (32 micrograms/ml/kg), dissolved in polyethylene glycols was injected into the stomach of 5 beagles, and only polyethylene glycols was injected into the stomach of the other 5 beagles as controls. Retinal tissue blood flow, heart rate, arterial blood pressure, pulmonary arterial pressure, central vein pressure, cardiac output, and systemic vessel resistance were measured over time and compared between the two groups. RESULTS: Retinal tissue blood flow showed significant increase only in the Nilvadipine group (max 29.2%). No marked changes were observed in the systemic circulation in either group. The time to maximum blood concentration of Nilvadipine was 120 min, and the maximum blood concentration was 1.27 ng/ml. CONCLUSION: Nilvadipine may directly and selectively increase retinal tissue blood flow, while having only minimal effect on systemic circulation including arterial blood pressure.

Preventive effect of lactobacillus delbrueckii subsp. bulgaricus on the oxidation of LDL.

Lactobacillus delbrueckii subsp. bulgaricus 2038 was examined for its activity to prevent the oxidation of the erythrocyte membrane in vitro, and the oxidation of LDL in vivo. Strain 2038 produced radical scavengers that reacted with 1,1-diphenyl-2-picrylhydrazl (DPPH) during cultivation. Moreover, the ethereal extract from the supernatant of the culture prevented the oxidation of the erythrocyte membrane in vitro. As an in vivo study, male F344 rats were fed on diets containing 20% fresh soybean oil (or 13% oxidized oil and 7% fresh oil) with 10% freeze-dried powder of the 2038 culture (or with skim milk powder) for 4 weeks. The level of thiobarbituric acid-reactive substances was lower in the low-density lipoproteins (per milligram of cholesterol) from rats fed on the oxidized oil with freeze-dried powder of the 2038 culture than without it. The level of vitamin E in the plasma was higher in the rats fed on the oxidized oil with the freeze-dried powder than without it.

Molecular design, synthesis, and hypoglycemic activity of a series of thiazolidine-2,4-diones.

A series of imidazopyridine thiazolidine-2,4-diones were designed and synthesized from their corresponding pyridines. These compounds represent conformationally restricted analogues of the novel hypoglycemic compound rosiglitazone (5). The series was evaluated for its effect on insulin-induced 3T3-L1 adipocyte differentiation in vitro and its hypoglycemic activity in the genetically diabetic KK mouse in vivo. The structure-activity relationships are discussed. On the basis of the in vivo potency, 5-[4-(5-methoxy-3-methyl-3H-imidazo[4, 5-b]pyridin-2-ylmethoxy)benzyl]thiazolidine-2,4-dione (19a) was selected as the candidate for further studies in a clinical setting.

Inhibition of nitric oxide by phenylethanoids in activated macrophages.

Nitric oxide (NO) is one of the pro-inflammatory molecules. Some phenylethanoids have been previously shown to possess anti-inflammatory effects. Seven phenylethanoids from the stems of Cistanche deserticola, viz. isoacteoside, tubuloside B, acteoside, 2'-O-acetylacteoside, echinacoside, cistanoside A and tubuloside A, were tested for their effect on NO radical generation by activated murine macrophages. At the concentration of 100-200 microM, all the phenylethanoids reduced (6.3-62.3%) nitrite accumulation in lipopolysaccharide (0.1 microgram/ml)-stimulated J774.1 cells. At 200 microM, they inhibited by 32.2-72.4% nitrite accumulation induced by lipopolysaccharide (0.1 microgram/ml)/interferon-gamma (100 U/ml) in mouse peritoneal exudate macrophages. However, these compounds did not affect the expression of inducible nitric oxide (iNOS) mRNA, the iNOS protein level, or the iNOS activity in lipopolysaccharide-stimulated J774.1 cells. Instead, they showed a clear scavenging effect (6.9-43.9%) at the low concentrations of 2-10 microM of about 12 microM nitrite generated from an NO donor, 1-propanamine-3-hydroxy-2-nitroso-1-propylhydrazino (PAPA NONOate). These results indicate that the phenylethanoids have NO radical-scavenging activity, which possibly contributes to their anti-inflammatory effects.

Enhancing effect of dietary oil emulsions on immune responses to protein antigens fed to mice.

Repeated intragastric administration of beta-lactoglobulin (beta-Lg) with emulsified soybean oil elicited an antigen-specific, systemic humoral immune response in different strains of mice. The antibody response was enhanced as the dose of oil was increased and the particle size of emulsions was decreased. Feeding of aqueous beta-Lg could induce the antibody response only when emulsified oil was fed almost simultaneously. However, the emulsion-driven humoral immune response was not observed when mice were treated with anti-CD40 ligand antibody or in athymic mice. It is likely that the intestinal coexistence of emulsified oil with dietary antigens modulates the immune system to crucially support B cell response. A practical application of the present results to the prevention of cow's milk protein sensitization in infants is proposed.

Predominant information transfer from layer III pyramidal neurons to corticospinal neurons.

Connections of layer III pyramidal neurons to corticospinal neurons of layer V and corticothalamic neurons of layer VI in the rat primary motor cortex were examined in brain slices by combining intracellular staining with Golgi-like retrograde labeling of corticofugal neurons. Forty layer III pyramidal neurons stained intracellularly were of the regular-spiking type, showed immunoreactivity for glutaminase, and emitted axon collaterals arborizing locally in layers II/III and/or V. Nine of them were reconstructed for morphologic analysis; 15.2% or 3.8% of varicosities of axon collaterals of the reconstructed neurons were apposed to dendrites of corticospinal or corticothalamic neurons, respectively. By confocal laser scanning and electron microscopy, some of these appositions were revealed to make synapses. These findings suggest that corticospinal neurons receive information from the superficial cortical layers four times more frequently than corticothalamic neurons. The connections were further examined by intracellular recording of excitatory postsynaptic potential (EPSP) that were evoked in layer V and layer VI pyramidal neurons by stimulation of layer II/III. EPSPs evoked in layer V pyramidal neurons showed short and constant onset latencies, suggesting their monosynaptic nature. In contrast, most EPSPs evoked in layer VI pyramidal neurons had long onset latencies, showed double-shock facilitation of onset latency, and were largely suppressed by an N-methyl-D-aspartic acid receptor blocker, suggesting that they were polysynaptic. The results suggest that information from the superficial cortical layers is transferred directly and efficiently to corticospinal neurons in layer V and thereby exerts an important influence on cortical motor output. Corticothalamic neurons are, in contrast, considered relatively independent of, or indirectly related to, information processing of the superficial cortical layers.

Complete structure of the chloroplast genome of a legume, Lotus japonicus.

The nucleotide sequence of the entire chloroplast genome (150,519 bp) of a legume, Lotus japonicus, has been determined. The circular double-stranded DNA contains a pair of inverted repeats of 25,156 bp which are separated by a small and a large single copy region of 18,271 bp and 81,936 bp, respectively. A total of 84 predicted protein-coding genes including 7 genes duplicated in the inverted repeat regions, 4 ribosomal RNA genes and 37 tRNA genes (30 gene species) representing 20 amino acids species were assigned on the genome based on similarity to genes previously identified in other chloroplasts. All the predicted genes were conserved among dicot plants except that rpl22, a gene encoding chloroplast ribosomal protein CL22, was missing in L. japonicus. Inversion of a 51-kb segment spanning rbcL to rpsl6 (positions 5161-56,176) in the large single copy region was observed in the chloroplast genome of L. japonicus. The sequence data and gene information are available on our World Wide Web database at http://www.kazusa.or.jp/en/plant/database.html.

Relationship between blood/air partition coefficients of lipophilic organic solvents and blood triglyceride levels.

The blood/air partition coefficient is one of the important parameters for understanding the pharmacokinetics of organic solvents. In conventional pharmacokinetic models, the partition coefficient has been used as a constant value for each solvent. However, blood triglyceride content varies according to a diet, and the variation may affect the partition coefficient of lipophilic organic solvents. In this study, the relationship between the blood/air partition coefficient of lipophilic organic solvents and plasma triglyceride concentrations was clarified. Corn oil (4.0 ml/kg) was administered orally to male Wistar rats, and blood samples were collected 3 h after the administration, when the plasma triglyceride level reached a peak. Control rats received the same amount of distilled water via the same route. The blood/air partition coefficients of five types of lipophilic solvents (m-xylene, trichloroethylene, 1,1,1-trichloroethane, chloroform and carbon tetrachloride) were determined in these two groups of blood samples. The hematological and biochemical parameters were also examined in the same blood samples. Although the mean plasma triglyceride level in the oil group increased about 3.3 times compared with that in the control group, the increase in the blood/air partition coefficients of the five lipophilic solvents was relatively low (approximately 1.2-1.5 times). We concluded that the diet has no significant effect on the blood/air partition coefficients of organic solvents, and the value can be used as a constant parameter for each solvent in a physiological simulation model.

Influence of finishing on the electrochemical properties of dental alloys.

Dental alloy surface finishing procedures of may influence their electrochemical behavior, which is used to evaluate their corrosion resistance. We examined the polarization resistance and potentiodynamic polarization profile of the precious-metal alloys, Type 4 gold alloy and silver-palladium alloy, and the base-metal alloys, nickel-chromium alloy, cobalt-chromium alloy, and CP-titanium. Three types of finishing procedure were examined: mirror-finishing using 0.05 micron alumina particles, polishing using #600 abrasive paper and sandblasting. Dissolution of the alloy elements in 0.9% NaCl solution was also measured and compared with the electrochemical evaluation. The corrosion resistance of the dental alloys was found to relate to finishing as follows: The polarization resistance and potentiodynamic polarization behavior revealed that the corrosion resistance improved in the order of sandblasting, #600-abrasive-paper polishing, and mirror-finishing. While the corrosion potential, critical current density and passive current density varied depending on the type of finishing, the transpassive potential remained unchanged. The influence of finishing on the corrosion resistance of precious-metal alloys was less significant than on that of base-metal alloys. A mirror-finishing specimen was recommended for use in evaluation of the corrosion resistance of various dental alloys.

Calcium-binding protein-immunoreactive projection neurons in the caudal subnucleus of the spinal trigeminal nucleus of the rat.

It has been reported that calcium-binding proteins are good markers for different sets of neurons in various brain regions. We examined expression of the main calcium-binding proteins in projection neurons in the rat medullary dorsal horn (MDH) by combining immunofluorescence histochemistry for calbindin D28k (CB), calretinin (CR) and parvalbumin (PV) with the retrograde tract-tracing method. A fluorescence tracer, tetramethylrhodamine-dextran amine (TMR-DA), was injected into the parabrachial, thalamic or hypothalamic region. After such injections, a number of PV-, CR-, and/or CB-immunoreactive MDH neurons were labeled retrogradely with TMR-DA. Triple-immunofluorescence histochemistry further revealed that a number of CB-, CR-, or PV-immunoreactive TMR-DA-labeled MDH neurons showed immunoreactivity for substance P receptor (NK1), and that they expressed immunoreactivity for c-fos protein in the rats which were injected with formalin into the lips. Thus, it was indicated that some of CB-, CR-, or PV-containing projection neurons in the MDH might be involved in the transmission of nociceptive stimuli.

Preprodynorphin-like immunoreactivity in medullary dorsal horn neurons projecting to the thalamic regions in the rat.

Preprodynorphin (PPD)-like immunoreactive (-LI) neuronal cell bodies in the trigeminal sensory nuclear complex of the rat were found in laminae I and II of the medullary dorsal horn (MDH; caudal spinal trigeminal nucleus) and the paratrigeminal nucleus. A PPD immunofluorescence histochemistry combined with a fluorescence retrograde tract-tracing method revealed that some of the PPD-LI neurons in the MDH and paratrigeminal nucleus projected to the thalamic regions. Nociceptive nature of the PPD-LI MDH neurons projecting to the thalamic regions was also demonstrated by a triple labeling method, using the technique of the noxious stimulus-evoked expression of the immediate-early gene, c-fos. In the rats which were subcutaneously injected with formalin into the upper and lower lips, c-fos protein (Fos) was found in PPD-LI neurons which were labeled with a retrograde tracer injected into the thalamic regions.

Immunocytochemical localization of prostaglandin EP3 receptor in the rat hypothalamus.

A rabbit antibody against an N-terminal portion of rat prostaglandin EP3 receptor (EP3R) was produced to examine the distribution of EP3R in the rat hypothalamus. The antibody specifically recognized EP3R proteins in rat brain extract, in membrane fractions of rat kidney, and in membrane fractions of EP3R-expressing culture cells. Intense EP3R-like immunoreactivity was observed in the median preoptic nucleus, medial preoptic area, parastrial nucleus, compact part of the dorsomedial hypothalamic nucleus, and dorsal part of the premammillary nucleus. These results suggest that prostaglandin E2 mediates various actions in the hypothalamus, such as fever induction in the preoptic area, through EP3R.