The Idealized Brazilian Health System versus the real one: contributions from the nursing field / O Sistema Único de Saúde idealizado versus o realizado: contribuições da Enfermagem / El Sistema Único de Salud idealizado versus el realizado: contribuciones de la Enfermería

OBJECTIVE: to identify the perceptions of professionals working in a facility connected with the Brazilian Unified Health System - SUS in regard to what they know, think and talk about public health policy. METHOD: this exploratory-descriptive study with a qualitative nature was conducted with 28 professionals working in a facility connected with the SUS. Data were collected through interviews with guiding questions and analyzed through the thematic content analysis technique. RESULTS: coded and interpreted data resulted in three thematic axes: The SUS - perfect web that does not work in practice; The recurrent habit of complaining about the SUS; The need to rethink the way of thinking about, acting in and managing the SUS. CONCLUSION: the professionals working for the SUS are aware of the principles and guidelines that govern the Brazilian health system, however, they reproduce a dichotomous and linear model of conception and practice strongly linked to the thinking of society in general. .

OBJETIVO: conhecer a percepção de profissionais que atuam em uma instituição conveniada com o Sistema Único de Saúde sobre o que sabem, pensam e falam dessa política pública de saúde. MÉTODO: trata-se de estudo exploratório-descritivo, de caráter qualitativo, realizado com 28 profissionais que atuam em uma instituição conveniada com o Sistema Único de Saúde. Os dados foram coletados por meio de entrevistas com questões norteadoras e analisados pela técnica de análise de conteúdo temática. RESULTADOS: os dados codificados e interpretados resultaram em três eixos temáticos: Sistema Único de Saúde - teia perfeita que não funciona na prática; o recorrente hábito de reclamar do Sistema Único de Saúde; a necessidade de repensar o modo de pensar, atuar e gerir o Sistema Único de Saúde. CONCLUSÃO: os profissionais que atuam no Sistema Único de Saúde têm conhecimento dos princípios e diretrizes que regem o sistema de saúde nacional, no entanto, reproduzem um modelo de concepção e atuação dicotômico, pontual e linear ainda fortemente vigente no pensar da sociedade em geral. .

OBJETIVO: conocer la percepción de profesionales que actúan en una institución que tiene convenio con el Sistema Único de Salud - SUS sobre lo que saben, piensan y hablan de esta política pública de salud. MÉTODO: se trata de un estudio exploratorio descriptivo, de carácter cualitativo, realizado con 28 profesionales que actúan en una institución que tiene convenio con el SUS. Los datos fueron recolectados por medio de entrevistas con preguntas orientadoras y analizados con la técnica de análisis de contenido temático. RESULTADOS: los datos codificados y interpretados resultaron en tres ejes temáticos: SUS - red perfecta que no funciona en la práctica; el recurrente hábito de reclamar del SUS; y la necesidad de repensar el modo de pensar, actuar y administrar el SUS. CONCLUSIÓN: los profesionales que actúan en el SUS tienen conocimiento de los principios y directrices que gobiernan el sistema de salud nacional, sin embargo, reproducen un modelo de concepción y actuación dicotómico, puntual, linear y además fuertemente vigente en el pensar de la sociedad en general. .

Maintenance of the corneal epithelium is carried out by germinative cells of its basal stratum and not by presumed stem cells of the limbus

The purpose of this investigation was to analyze the proliferative behavior of rabbit corneal epithelium and establish if any particular region was preferentially involved in epithelial maintenance. [3H]-thymidine was injected intravitreally into both normal eyes and eyes with partially scraped corneal epithelium. Semithin sections of the anterior segment were evaluated by quantitative autoradiography. Segments with active replication (on) and those with no cell division (off) were intermingled in all regions of the tissue, suggesting that the renewal of the epithelial surface of the cornea followed an on/off alternating pattern. In the limbus, heavy labeling of the outermost layers was observed, coupled with a few or no labeled nuclei in the basal stratum. This suggests that this region is a site of rapid cell differentiation and does not contain many slow-cycling cells. The conspicuous and protracted labeling of the basal layer of the corneal epithelium suggests that its cells undergo repeated cycles of replication before being sent to the suprabasal strata. This replication model is prone to generate label-retaining cells. Thus, if these are adult stem cells, one must conclude that they reside in the corneal basal layer and not the limbal basal layer. One may also infer that the basal cells of the cornea and not of the limbus are the ones with the main burden of renewing the corneal epithelium. No particular role in this process could be assigned to the cells of the basal layer of the limbal epithelium.

Separation, purification and primary reverse cholesterol transport study of Cordyceps militaris polysaccharide / 中国中药杂志

The authors designed to separate, purify and determine the monosaccharide composition of the polysaccharide from Cordyceps militaris, and study its effect on reverse cholesterol transport in vivo by isotope tracing assay. Polysaccharides were separate and purify by ion exchange column Q-sepharose Fast Flow and size exclusion column Sephacryl S200HR; the molecular weight and monosaccharide composition of the polysaccharides were determined by high performance gel permeation chromatography and high performance liquid chromatography coming with pre-column derivation, respectively. Finally, three purified polysaccharides CMBW1, CMBW2 and CMYW1 were obtained, their total carbohydrate contents were 87%, 89%, 95%, respectively; their protein contents were 6.5%, 1.3%, 2.8%, respectively; their molecular weights were 772.1, 20.9, 13.2 kDa, respectively; CMBW1 was composed of mannose, glucosamine, rhamnose, glucuronic acid, glucose, galactose and arabinose with a molar ratio of 7.25: 0.17: 1.29: 0.23: 6.30: 11.08: 0.79; CMBW2 was composed of mannose, glucosamine, galactose and arabinose with a molar ratio of 2.40: 0.16: 2.92: 0.24; CMYW1 was composed of mannose, glucosamine, glucuronic acid and glucose with a molar ratio of 0.59: 0.57: 0.45: 25.61. Polysaccharide at 50 mg x kg(-1) could significantly improve the transport of 3H- cholesterol to blood and excretion from feces. All of the three purified polysaccharides CMBW1, CMBW2 and CMYW1 were heteropolysaccharide; and they could improve reverse cholesterol transport in vivo, the underlying mechanisms are being studied.

In vitro & in vivo estrogenic activity of glycoside fractions of Solanum nigrum fruit.

Background & objectives: The mature fruits of Solanum nigrum contains steroidal glycosides. These are often used as vegetable and there are evidences on tribal use of these fruits as an oral contraceptive. The present study was carried out to evaluate the estrogenic potential of S. nigrum fruits by in vitro and in vivo assays. Methods: Defatted methanol extract of dried S. nigrum fruits was column fractionated and the glycoside positive fractions pooled. Definite concentrations of the fraction were used for in vitro and in vivo assays. The effect on cell viability was analyzed in MCF-7 cell lines by MTT assay followed by in vitro evaluation of estrogenicity by hydroxy apatite (HAP) binding assay. The results were further evaluated in vivo by performing uterotrophic assay in ovariectomized mouse models. Results: At low concentration (40 μg/ml), SNGF induced a dose-dependent increase in MCF-7 cell proliferation, while higher extract concentrations (80-320 μg/ml) caused progressive cell growth inhibition. The competitive binding assay using 3H-E2 suggests that this effect is mediated by estrogen receptor. Mouse uterotrophic assay revealed a classical uterotrophic response in ovariectomized mice in response to S. nigrum glycoside fraction (SNGF). SNGF at a dose of 100 mg/kg of body wt induced the maximum height of luminal epithelial cells which indicated an increase of 30.8 per cent over control (P<0.01) with a correlated increase in uterine wet wt (150% increase over control). Higher doses (250 and 500 mg/kg body wt) of SNGF did not induce any uterotrophic effect. Interpretation & conclusions: Our preliminary data demonstrate the hormone like activity of Solanum glycosides both in vitro and in vivo in mouse, which needs to be further explored to evaluate the possible mechanism and clinical implications.

Research on relationship between tissue quantitative distribution of 3H-Achyranthes bidentata ecdysterone and channel-tropism of herbal drugs in mice / 中国中药杂志

<p><b>OBJECTIVE</b>To study the relationship between tissue quantitative distribution and pharmacokinetics of 3H-achyranthes bidentata ecdysterone and the channel-tropism of herbal drugs in mice.</p><p><b>METHOD</b>3H-achyranthes bidentata ecdysterone was used as a tracer agent and injected into mice by the caudal vein. In 36 hours, the contents of the tracer agent of samples involving 9 different tracing phases and organ or tissue were determined in order to observe the dynamic quantitative distribution and excretion and pharmacokinetics of 3H-achyranthes bidentata ecdysterone and to understand the channel-tropism of herbal drugs achyranthes bidentata.</p><p><b>RESULT</b>3H-achyranthes bidentata ecdysterone of same organs in different tracing phases and the contents of 3H-achyranthes bidentata ecdysterone in same tracing phases of different organs were significantly different (P<0.01). 3H-achyranthes bidentata ecdysterone was mainly distributed, in the liver, kidney, adrenal gland, small intestine and lung. The concentration-time profiles of achyranthes bidentata ecdysterone in rats injected into mice by the caudal vein were shown to fit a two-compartment open model with half-lives of (778.65 +/- 12.36) min, the elimination of achyranthes bidentata ecdysterone from plasma was found to be in accord with linear kinetics.</p><p><b>CONCLUSION</b>The above mentioned selective distribution of 3H-achyranthes bidentata ecdysterone basically coincides with the meridian affinity and zang fu selection of the traditional Chinese medicine drug Achyranthes bidentata. This study will provide a scientific basis for the channel-tropism of A. bidentata.</p>

Wheat germ oil attenuates gamma radiation-induced skeletal muscles damage in rats

Muscular strength is important in sport as well as in daily activities. Exposure to ionizing radiation is thought to increase oxidative stress and damage muscle tissue. Wheat germ oil is a natural unrefined vegetable oil. It is an excellent source of vitamin E, octacosanol, linoleic and linolenic essential fatty acids, which may be beneficial in neutralizing the free oxygen radicals. The present study was designed to investigate the efficacy of wheat germ oil, on radiation-induced oxidative damage in rat's skeletal muscle. Wheat germ oil was supplemented orally via gavages to rats at a dose of 54 mg/ kg body weight/day for 14 successive days pre- and 7 post-exposure to 5 Gy [one shot dose] of whole body gamma irradiation. Animals were sacrificed 7, 14 and 21 days post radiation exposure. The results revealed that whole body gamma-irradiation of rats induces oxidative stress in skeletal muscles obvious by significant elevation in the level of thiobarbituric acid reactive substances [TEARS] associated with significant decreases in the content of reduced glutathione [GSH], as well as decreases in superoxide dismutase [SOD], catalase [CAT] and glutathione peroxidase [GSH-Px] activities. Irradiated rats showed, also, significant decreases in creatine phosphokinase [CPK], glutamate dehydrogenase [GDH] and glucose-6-phosphate dehydrogenase [G-6-PD] activities. Furthermore, total iron, total copper and total calcium levels were significantly increased in skeletal muscles of irradiated rats group compared to control group. Wheat germ oil treated-irradiated rats showed significantly less severe damage and remarkable improvement in all the measured parameters, compared to irradiated rats. It could be concluded that wheat germ oil by attenuating radiation-induced oxidative stress might play a role in maintaining skeletal muscle integrity

Effect of sodium tanshinone II A sulfonate on cardiac myocyte hypertrophy and its underlying mechanism / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the effects of sodium tanshinone II A sulfonate (STS) on the hypertrophy induced by angiotensin II (Ang II) in primary cultured neonatal rat cardiac myocytes.</p><p><b>METHODS</b>The effect of STS on cytotoxicity was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-3,5-phenytetrazoliumromide (MTT) assay. As indexes for cardiocyte hypertrophy, cell size was determined by phase contrast microscopy and protein synthesis rate was measured by 3H-leucine incorporation. The proto-oncogene c-fos mRNA expression of cardiocytes was assessed using reverse transcription polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>STS could inhibit cardiocyte hypertrophy, increase the protein synthesis rate and enhance proto-oncogene c-fos mRNA expression in cardiocytes induced by Ang II (P<0.01), with an effect similar to that of Valsartan, the Ang II receptor antagonist.</p><p><b>CONCLUSION</b>STS can prevent the hypertrophy of cardiac myocytes induced by Ang II, which may be related to its inhibition of the expression of proto-oncogene c-fos mRNA.</p>

Effect of sodium tanshinone II A sulfonate on phosphorylation of extracellular signal-regulated kinase 1/2 in angiotensin II-induced hypertrophy of myocardial cells / 中国结合医学杂志

<p><b>OBJECTIVE</b>To observe the effects of sodium tanshinone II A sulfonate (STS) on angiotensin II (Ang II)-induced hypertrophy of myocardial cells through the expression of phosphorylated extracellular signal-regulated kinase (p-ERK1/2).</p><p><b>METHODS</b>In the primary culture of neonatal rat myocardial cells, the total protein content in myocardial cells was determined by coomassie brilliant blue and the protein synthesis rate was measured by [3H]-Leucine incorporation as indexes for hypertrophy of myocardial cells. The expression of p-ERK1/2 was determined using Western blot and immunofluorescence labeling.</p><p><b>RESULTS</b>(1) The total protein and protein synthesis rate increased significantly in contrast to the control group after the myocardial cells were stimulated by Ang II (1 micromol/L) for 24 h; STS markedly inhibited the increment of the total protein level induced by Ang II and the syntheses of protein. (2) After pretreatment of myocardial cells with Ang II (1 micromol/L) for 5 min, the p-ERK1/2 protein expression was increased, with the most obvious effect shown at about 10 min; pretreatment of myocardial cells with STS at different doses (2, 10, 50 micromol/L) for 30 min resulted in obvious inhibition of the expression of p-ERK1/2 stimulated by Ang II in a dose-dependent manner. (3) After the myocardial cells were stimulated by Ang II (1 micromol/L), the immunofluorescence of ERK1/2 rapidly appeared in the nucleus. The activation and translocation process of ERK1/2 induced by Ang II was blocked distinctly by STS.</p><p><b>CONCLUSION</b>STS inhibited the myocardial cell hypertrophy induced by Ang II, and the mechanism may be associated with the inhibition of p-ERK1/2 expression.</p>

Effects of bushen tiaochong recipe containing serum on ovarian granulosa cell proliferation, steroidogenesis and associated gene expression in rats / 中国结合医学杂志

<p><b>OBJECTIVE</b>To observe the effect of bushen tiaochong recipe (BSTCR) on rats' ovarian granulosa cell (GC) proliferation, steroidogenesis and follicle-stimulating hormone receptor (FSHR), and insulin-like growth factor-1 (IGF-1) mRNA expression using serum pharmacological method.</p><p><b>METHODS</b>Rats' GCs were incubated with 10% blank serum (as negative control group), follicle-stimulating hormone (FSH)-containing serum (S-FSH, as positive control group), or BSTCR (in different dosages) containing serum (S-BSTCR, as the BSTCR groups) for 48 h. 3H-TdR incorporation was then performed; DNA was measured to analyze the distribution of GCs in the cell cycle and their proliferation index (PI) using a flow cytometer; estradiol (E2) and progesterone (P) content in the culture fluid were examined by radioimmunoassay; and levels of FSHR and IGF-1 mRNA expression in GCs were measured by real-time RT-PCR.</p><p><b>RESULTS</b>A dose-dependent increase of 3H-TdR incorporation in GC was shown in the BSTCR groups. Cells in G0/G1 phase had markedly less, while those in S phase had a significantly higher increase in the BSTCR groups compared with the negative control group. A high value of PI was also shown in the BSTCR groups, especially in the high dose group where the influence of cell proliferation was stronger than that in the positive control group. The levels of E2 and P in the BSTCR groups of all dosages were significantly higher than those in the negative control group, and did not show any significant difference compared with those in the positive control group. Levels of FSHR and IGF-1 mRNA expression in the BSTCR groups increased in a dose-dependent manner at levels higher than those in the negative control group.</p><p><b>CONCLUSION</b>S-BSTCR can obviously stimulate the proliferation and steroidogenesis of ovarian GCs. It is speculated that BSTCR could play a regulatory action on ovarian function through two different pathways of endocrine and autocrine by promoting FSHR and IGF-1 mRNA expression.</p>

Pharmacokinetics and biodistribution of 3H-norcantharidin in mice / 药学学报

A single dose of 3H-norcantharidin solution was intragastrically given, blood, tissues, urine and feces were collected as scheduled, and radioactivity in these samples was determined by tritium tracing method to investigate the pharmacokinetics, tissue distribution and excretion of norcantharidin in Kunming mice. The pharmacokinetic characteristics of norcantharidin were evaluated by DAS version 2.0. The blood concentration reached to maximum 0. 5 h after intragastric administration. The radioactivity in tissues was high in small intestine, gallbladder, stomach, adrenal gland, kidney, heart and uterus 15 minutes after administration, descending with time, and high in gallbladder, adrenal gland and uterus 3 hours post dosing. The 24 h accumulative excretion ratio of urine and feces were 65.40% and 1.33% respectively. 3H-norcantharidin was easily absorbed after orally given to mice, the radioactivity was high and existed for a long-time in gallbladder, adrenal gland and uterus, and low but also existed for a long-time in large intestine, thymus and fat tissue. 3H-norcantharidin was declined quickly in small intestine, stomach, kidney and heart, and occurred rarely in brain. Norcantharidin was excreted mainly by urinary route and seldom in feces, which may be the cause of the urinary stimulation side effects observed. Because the radioactivity measured were the sum of 3H labeled norcantharidin and its metabolites, further studies on the disposition of norcantharidin in mammal animals, on the separation or identification of metabolites and, if any, on their activities, are fairly needed.

Detection of binding activity and biologic effect of a novel alpha-melanocyte-stimulating hormone analogue / 药学学报

Binding activity and biologic effect of a novel alpha-melanocyte-stimulating hormone analogue were tested on cells transiently expressing the human melanocortin-1 (MC1), MC3, MC4, and MC5 receptors. The human MC1 and MC5 receptor genes were cloned into the expression vector pcDNA3. 1/ myc-his(-) B. The vectors were transferred to HEK-293 cells by the calcium phosphate method. Stable receptor populations were generated using G418 selection (900 microg x mL(-1)) for subsequent bioassay analysis. K(i) values of the novel alpha-MSH analogue for MC1, MC3, MC4, and MC5 receptors were obtained in competition with [125I]-NDP-MSH for binding studies. The cyclic AMP level was tested by using [3H]-cyclic AMP kit. It is showed that K(i) values of the novel alpha-MSH analogue for MC1, MC3, MC4, and MC5 receptors were (0.159 +/- 0.040), (35.430 +/- 6.743), (19.293 +/- 2.780) and (2.230 +/- 0.670) nmol L(-1), respectively. Its EC50 values for MC1, MC3, MC4, and MC5 receptors were (0.45 +/- 0.07), (7.80 +/- 0.65), (2.55 +/- 0.23) and (0.33 +/- 0.09) nmol L(-1), respectively. In these tests, the novel alpha-MSH analogue is a MC1R and MC5R selective agonist.

Effects of 2-deoxy-D-glucose and quercetin on osteoblastic differentiation and mineralization in irradiated MC3T3-E1 cells / 대한구강악안면방사선학회지

PURPOSE: To investigate the in vitro response of MC3T3-E1 osteoblastic cells to X-ray in the presence and absence of 2 deoxy-D-glucose (2-DG) and quercetin (QCT). MATERIALS AND METHODS: The MC3T3-E1 cells were cultured in an alpha-MEM supplemented with 5 mM 2-DG or 10 micrometer QCT and then the cells were incubated for 12 h prior to irradiation with 2, 4, 6, and 8 Gy using a linear accelerator (Mevaprimus, Germany) delivered at a rate of 1.5 Gy/min. At various times after the irradiation, the cells were processed for the analyses of proliferation, viability, cytotoxicity, and mineralization. RESULTS: Exposure of the cells to X-ray inhibited the tritium incorporation, 3-(4, 5-dimethylthiazol-2yl-)-2, 5- diphenyl tetrazolium bromide (MTT)-reducing activity, and alkaline phosphatase (ALP) activity, and caused cytotoxicity and apoptosis in a dose-dependent manner of the X-ray. This effect was further apparent on day 3 and 7 after the irradiation. RA+2-DG showed the decrease of DNA content, cell viability, and increase of cytotoxicity rather than RA. ALP activity increased on day 7 and subsequently its activity dropped to a lower level. 2-DG suppressed the calcium concentration, but visual difference of number of calcified nodules between RA and RA+2-DG was not noticed. RA+QCT showed the increase of DNA content, cell viability, but decrease of cytotoxicity and subG1 stage cells in the cell cycle, and increased calcified nodules in von Kossa staining rather than the RA. ALP activity showed significant increases on day 7 and subsequently its activity dropped to a lower level. CONCLUSION: The results showed that the 2-DG acted as a radiosensitizing agent and QCT acted as a radioprotective agent respectively in the irradiated MC3T3-E1 osteoblast-like cells.

Effect of human bone marrow mesenchymal stem cell on cord blood T lymphocyte transformation / 中国实验血液学杂志

To study the effect of mesenchymal stem cell (MSC) on immune function, MSCs were isolated and cultured from human bone marrow cells. The purity of MSCs were identified with the spindle-fibroblastic morphology characterization by microphotograph and the phenotypes were tested by flow cytometry. MSCs were plated in 96-well plates (2,000/well and 1,000/well), and cocultured for 3 days with T cells isolated from cord blood. Cord blood T cells non-cocultured with MSC acted as control group. After cord blood T cells stimulated by PHA for 60 hours, [(3)H]-thymidine was added to each well and T cell proliferation was assessed by [(3)H] thymidine incorporation. The results showed that cord blood T cell proliferation was suppressed when 2,000 MSCs were plated each well and cord blood T cell proliferation was activated when 1,000 MSCs were plated. Our results suggested that the immunomodulatory function of MSC seemed dependent on cell dose. High concentration of MSC most often resulted in inhibition, while low concentration resulted in stimulation.

The Role of 5-HT Receptors on the Acetylcholine Release from the Rat Striatum / 대한정신약물학회지

The aim of this study was to investigate the role of the 5-HT receptors in acetylcholine (ACh) release from the striatum. Slices from the rat striatum and synaptosomes were incubated with [3H]-choline and the release of the labelled products was evoked by electrical (3 Hz, 2 ms, 5 V/cm, rectangular pulses, 2 min) and potassium-stimulation (25 mM), respectively, and the influence of various serotonergic drugs on the evoked tritium outflows was investigated. Serotonin decreased the electrically-evoked ACh release in striatum in a concentration-dependent manner without the change of basal release. In hippocampal and entorhinal cortical slices, serotonin did not affect the evoked and basal release of ACh, but, at large dose (30 microM) decreased the evoked ACh release in hippocampus. 2,5-Dimethoxy-4-iodoamphetamine (DOI), a specific 5-HT 2A/2C agonist, decreased evoked ACh release in the striatum. CGS-12066A (5-HT 1B agonist), m-chlorophenyl-biguanide (5-HT 3 agonist) and 5-[(dimethyl -amino)methyl]-3-(1-methyl-1H-indol-3-yl)-1,2,4-oxadiazole (5-HT 3 antagonist) did not affect the evoked and basal ACh release in all tissues. Ritanserin, a specific 5-HT 2A/2C antagonist, blocked the inhibitory effects of serotonin and DOI, whereas, ketanserin, an another type of specific 5-HT 2A/2C antagonist did not affect the inhibitory effects of serotonin and DOI. In striatal synaptosomal preparation, serotonin and DOI did not affect the K +-evoked ACh release. These findings suggest that ritanserin-sensitive 5-HT 2A/2C receptors located in the soma and/or axons of the striatal cholinergic neurons play a important role in ACh release.

Characteristics of A|1 and A|2 adenosine receptors upon the acetylcholine release in the rat hippocampus

As it has been reported that the depolarization induced acetylcholine (ACh) release is modulated by activation of presynaptic A1 adenosine heteroreceptor and various lines of evidence suggest the A2 adenosine receptor is present in the hippocampus. The present study was undertaken to delineate the role of adenosine receptors on the hippocampal ACh release. Slices from the rat hippocampus were equilibrated with (3H)choline and then the release amount of the labelled product, (3H)ACh, which was evoked by electrical stimulation (rectangular pulses, 3 Hz, 2 ms, 24 mA, 5 V/cm-1, 2 min), was measured, and the influence of various adenosine receptor-related agents on the evoked tritium outflow was investigated. And also, the drug-receptor binding assay was performed in order to confirm the presence of A1 and A2 adenosine receptors in the rat hippocampus. N-ethylcarboxamidoadenosine (NECA), a potent adenosine receptor agonist with nearly equal affinity at A1 and A2 adenosine receptors, in concentrations ranging from 1apprx30 muM, decreased the electrically-evoked (3H)ACh release in a concentration-dependent manner without affecting the basal rate of release. And the effect of NECA was significantly inhibited by 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, 2 micrometer), a selective A1 adenosine receptor antagonist, but was not influenced by 3,7-dimethyl-1-propargylxanthine (DMPX, 5 micrometer, a specific A2 adenosine receptor antagonist. N6-Cyclopentyladenosine (CPA), a selective A1 adenosine receptor agonist, in doses ranging from 0.1 to 10 micrometer, reduced evoked (3H)ACh release in a dose-dependent manner without the change of the basal release. And the effect of CPA was significantly inhibited by 2 micrometer DPCPX treatment. 2-P-(2-carboxyethyl)-phenethylamino-5'-N-ethylcarboxamidoadenosine hydrochloride (CGS-21680C), a potent A2 adenosine receptor agonist, in concentrations ranging from 0.1 to 10 micrometer, did not alter the evoked ACh release. In the drug-receptor binding assay, the binding of (3H)2-chloro-N6-Cyclopentyladenosine ((3H)CCPA) to the- A1 adenosine receptor of rat hippocampal membranes was inhibited by CPA (Ki = 1.22 nM), NECA (Ki=10.17 nM) and DPCPX (Ki-161.86 nM), but not by CGS-21680C (Ki=2,380 nM) and DMPX (Ki-22,367 nM). However, the specific binding of (3H)CGS-21680C to the A2 adenosine receptor was not observed. These results suggest that the A1 adenosine heteroreceptor play an important role in evoked ACh release, but the presence of A2 adenosine receptor is not confirmed in this study.

Muscarinic M1 and M3 receptor in rat striatum: A binding study

In this study, the authors set out to determine the presence of M3 muscarinic receptors in rat striatum by examining the binding of [3H]N-methyl-scopolamine([3H]NMS) to striatal membranes and its displacement by antagonists with different affinity for M1 and M3 muscarinic receptors (pirenzepine; 4-diphenylacetoxy-N-methylpiperidine methiodide, 4-DAMP; and the p-fluoro analog of hexahydro-sila-difenidol, pFHHSiD). The specific binding of [3H]NMS to membranes from rat striatum (551 ñ 40 fmol.mg prot.-1, KD 0.11 ñ 0.01 nM) was displaced in a concentration-dependent manner by all three antagonists tested. Inhibition curves best fit to a single-site model for 4-DAMP(pKi 9.1 ñ 0.1), whereas for both pirenzepine and pFHHSiD, the best fit was to the two-site model. The pKi values for the high-affinity (8.0 ñ 0.2) and low-affinity (6.7 ñ 0.2) components for pirenzepine-mediated inhibition of [3H]NMS binding correspondend to those reported for M1 and M3 receptors, respectively. The pKi values for the high-affinity (7.7 ñ 0.1) and low-affinity (7.1 ñ 0.2) components for pFHHSiD inhibition were in good agreement with those reported for M3 and M1 receptors, respectively. Altogether, these results indicate the presence in rat striatum of both M1 and M3 muscarinic receptors. These findings might be relevant to the design and use of mucarinic antagonists in the treatment of neurological disorders such as Parkinson's disease

Use of isotopically radiolabelled GM3 ganglioside to study metabolic alterations in Salla disease.

We report the preparation of radioactive GM3 ganglioside and its use in the study of sialic acid storage disorders. For the first time GM3 was isotopically radiolabeled in three positions of the molecule: at the sialic acid acetyl group, [3H-Neu5Ac]GM3, at the C1 of the fatty acid moiety, [14C-Stearoyl]GM3, and at C3 of sphingosine, [3H-Sph]GM3. The radioactive GM3 administered to cultured human fibroblasts from a patient suffering from Salla disease was taken up by the cells and metabolized. An analysis of the distribution of radioactivity within the ganglioside metabolic derivatives showed an accumulation of free sialic acid and ceramide in the pathological cells.

The role of adenosine receptors on acetylcholine release in the rat striatum

As it has been reported that the depolarization induced acetylcholine (ACh) release is modulated by activation of presynaptic A-1 adenosine heteroreceptor and various evidence suggest that indicate the A-2 adenosine receptor is present in the striatum, this study was undertaken to delineate the role of adenosine receptors on the striatal ACh release. Slices from the rat striatum were equilibrated with (3H)choline and then the release amount of the labelled product, (3H)ACh, which was evoked by electrical stimulation (rectangular pulses, 3 Hz, 2 ms, 24 mA, 5 Vcm-1, 2 min), was measured, and the influence of various agents on the evoked tritium outflow was investigated. And also, quantitative receptor autoradiography and drug-receptor binding assay were performed in order to confirm the presence and characteristics of A-1 and A-2 adenosine receptors in the rat striatum. Adenosine (10 ~ 100 micrometer) and N-6-cyclopentyladenosine (CPA, 1 ~ 100 micrometer) decreased the (3H)ACh release in a dose-dependent manner without changing the basal rate of release in the rat striatum. The reducing effects of ACh release by adenosine and CPA were abolished by 8-cyclopentyl-1,3-dipropy-lxanthine (DPCPX, 2 micrometer), a selective A-1 adenosine receptor antagonist, treatment. The effect of adenosine was potentiated markedly by 3,7-dimethyl-1-propargylxanthine (DMPX, 10 micrometer), a specific A-2 adenosine receptor antagonist. 2-P-(2-carboxyethyl)phenethylamimo-5'-N- ethylcarboxamidoadenosine hydrochloride (CGS-21680C), in concentrations ranging from 0.01 to 10 micrometer, a recently introduced potent A-2 adenosine receptor agonist, increased the(3 H)ACh release in a dose related fashion without changing the basal rate of release. These effects were completely abolished by DMPX (10 micrometer). In autoradiogaphy experiments, (3H)2-chloro-N-6-cyclopentyladenosine ((3 H)CCPA) bindings were highly localized in the hippocampus and the cerebral cortex. Additionally, lower levels of binding were found in the striatum. However, (3H)CGS-21680C bindings were highly localized in the striatal region with the greatest density of binding found in the caudate nucleus and putamen. Lower levels of binding were also found in the nucleus accumbens and olfactory tubercle. In drug-receptor binding assay, binding of (3H)CCPA to A-1 adenosine receptors of rat striatal membranes was inhibited by CPA (K-i = 1.6nM) and N-ethylcarboxamidoadenosine (NECA, K-i = 12.9 nM), but not by CGS-21680C (K-i = 2609.2 nM) and DMPX (K-i = 19,386 nM). In contrast, (3H)CGS-21680C binding to A-2 adenosine receptors was inhibited by CGS-21680C (K-i = 47.6 rim) and NECA (K-i = 44.9 nM), but not by CPA (K-i = 2099.2 nM) and DPCPX (K-i = 19,207 nM). The results presented here suggest that both types of A-1 and A-2 adenosine heteroreceptors exist and play an important role in ACh release in the rat striatal cholinergic neurons.

The influence of N-6-cyclopentyladenosine and magnesium on norepinephrine release in the rat hippocampus

As it has been reported that the depolarization-induced norepinephrine (NE) release is modulated by activation of presynaptic A-1-adenosine heteroreceptor and various lines of evidence indicate that A-2-adenosine receptor also presents in hippocampus, and that the adenosine effect is magnesium dependent, the present study was undertaken to delineate the role of adenosine receptors in the modulation of hippocampal NE release. Slices from the rat hippocampus were equilibrated with (3H)-NE and the release of the labelled product, (3H)-NE, was evoked by electrical stimulation (3 Hz, 5 V cm-1, 2 ms, rectangular pulses), and the influence of various agents on the evoked tritium outflow was investigated. N-6-cyclopentyladenosine (CPA), in concentrations ranging from 0.1 to 10 micrometer, decreased the (3H)-NE release in a dose-dependent manner without changing the basal rate of release, and these effects were significantly inhibited by 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, 2 micrometer) treatment. When the magnesium concentration was reduced to 0.4 mM or completely removed, the evoked NE release increased along with decreased basal rate of release. In contrast, increasing the magnesium concentrations to 2.4 and 4 mM, decreased the evoked NE release. The CPA effects on evoked NE release were reduced by magnesium removal, but potentiated by 2.4 mM magnesium in the medium. 5-(N-cyclopropyl)-carboxamodiadenosine (CPCA, 1 & 10 micrometer), an A-2-agonist, decreased the evoked tritium outflow, and this effect was also abolished by DPCPX pretreatment. CGS, a powerful A-2-agonist, did not affect the evoked NE release. However, the effects of CPCA and CGS on evoked NE release were significantly increased by pretreatment of DPCPX in the magnesium-free medium. These results indicate that inhibitory effect of A-1-adenosine receptor on NE release is magnesium-dependent, and A-2-receptor may be present in the rat hippocampus.

Does the release of tritiated noradrenaline accuratelly reflect the realease of endogenous noradrenaline from rat vas deferens nerve terminals?

To determine whether the release of tritiated noradrenaline (NA) from the sympathetic nerve terminals of the rat vas deferens is an accurate reflection of the release of endogenous NA, we compared the electrically-evoked release of tritiated and endogenous NA from the prostatic sections of the vasa deferentia of male rats. We found that while the release of tritiated NA was completely dependent on the presence of calcium, the release of endogenous NA was not. The overflow of both, tritiated and endogenous NA, was virtually unaffected by blockade of the neuronal uptake mechanism by desipramine. In contrast, blockade of the extraneuronal uptake greatly increased the overflow of endogenous NA, while having no effect on the overflow of tritiated NA. Tritiated NA release, on the other hand, was sensitive to prejunctional regulation, while the release of endogenous NA was not. Increases in stimulus train duration induced a significant increase in the release of endogenous NA, but not in that of tritiated NA. In contrast, the later responded to lower stimulus train frequencies and reached a plateau at lower frequency values as compared to the endogenous NA release. Our results indicate the existence of marked differences between the release of tritiated and endogenous NA. We conclude that: 1) the assumption that tritiated NA release provides a good marker for endogenous NA release in the rat was deferens seems unwarranted; 2) the use of endogenous NA to study the release process in the vas deferens requires a re-examination of the experimental conditions used, in order to minimize possible artifacts that may obscure the study of neuronal release; 3) the choice between measuring the release of tritiated or endogenous NA must be evaluated for each tissue in particular, taking into account its cytoarchitecture, as well as the experimental conditions used