bluuebunny/crossref_metadata_2025_split huggingface dataset:
Noradrenergic sympathetic innervation of the spleen: II. Tyrosine hydroxylase (TH)‐positive nerve terminals form synapticlike contacts on lymphocytes in the splenic white pulp
Authors: Felten S. Y. , Olschowka J. 
Published: January 2005

AbstractImmunocytochemistry was used to demonstrate tyrosine hydroxylase (TH)‐positive profiles in the spleen of the adult Fischer 344 rat. At the light microscopic level, numerous varicose nerve profiles were seen in the white pulp, particularly surrounding the central arteries and their arteriole branches. At the electron microscopic level, varicosities were seen in close proximity to smooth muscle cells of the arteries, and directly abutting lymphocytes (presumable T‐lymphocytes) of the nearby periarteriolar lymphatic sheath. There were no intervening cell processes between the TH‐positive terminals and the lymphocyte. The opposing membranes were smooth and evenly spaced approximately 6 nm apart. Additional TH‐positive nerve profiles were seen in the inner marginal zone and within trabeculae. The correlation between this immunocytochemical staining and previously demonstrated histofluorescence for norepinephrine leads to the conclusion that lymphocytes in the splenic white pulp have direct associations with noradrenergic fibers of the sympathetic nervous system. This association provides a route by which the autonomic nervous system could directly influence specific immune system effector cells.
Noradrenergic sympathetic innervation of the spleen: III. Development of innervation in the rat spleen
Authors: Ackerman K. D. , Felten S. Y. , Bellinger D. L. , Felten D. L. 
Published: January 2005

AbstractThe ontogeny of noradrenergic innervation and its compartmental devlopment were studied in the rat spleen using glyoxylic acid histofluorescence and high‐performance liquid chromatography (HPLC). Noradrenergic nerves were present at birth in bundles adjacent to the splenic artery and vein. On days 1‐3, fluorescent profiles largely were associated with the vasculature and with the perivascular zone. By day 6, these fibers formed increasingly elaborate and tortuous plexuses around the central arteries and their branches. By day 10, fibers were present along the marginal sinus and extended into the developing marginal zone. Between day 10 and day 13 the largest increase in norepinephrine (NE) levels (per mg protein) were noted, and the periarteriolar lymphatic sheath (PALS) achieved its adult form, with increased innervation of the parenchyma. In contrast, the venous/trabecular system developed relatively late. The first trabecular fibers were evident at day 10, and the capsule was not innervated until day 13. From 13 days to adulthood, there was a gradual refinement and extension of existing patterns with no change in NE levels as measured by HPLC (per mg protein), suggesting that the innervation was keeping pace with rapid increases in spleen growth.The pattern of growth and development for noradrenergic nerves in the PALS remarkably parallels changes in T cell compartmentation during this period. We propose that norepinephrine is available for interaction with T cells at the earliest stages of development and could play a role in such precesses as lymphocyte packing and the onset of immunocompetence.
Interleukin‐2 inhibition of oligodendrocyte progenitor cell proliferation depends on expression of the TAC receptor
Authors: Saneto R. P. , Chiappelli F. , de Vellis J. 
Published: January 2005

AbstractInterleukin‐2 (IL‐2) has been shown to inhibit oligodendroctye progenitor cell proliferation. Within the immune system, IL‐2 biological action is dependent strictly on the expression of the IL‐2 receptor. The antibody TAC, whcih specifically binds the lymphocyte IL‐2 receptor, has been shown to also bind oligodendrocyte progenitor cells cultured in a serumless, chemically defined medium. The expression of the TAC antigen was found necessary for IL‐2 inhibition of oligodendrocyte progenitor cell proliferation. After IL‐2 induced down‐regulation of the TAC antigen, the progenitor cell was unresponsive to IL‐2, even 72 hr after IL‐2 withdrawal. During this unresponsiv period, the oligodendrocyte progenitor cell was immunocytochemically negative for the TAC antigen. Thus, in contrast to IL‐2 receptors on T‐cells, IL‐2 does not up‐regulate its receptor on oligodendrocyte progenitor cells. However, upon interleukin 1 (IL‐1) addition both IL‐2 responsiveness and TAC immunocytochemical staining reappeared. These data suggest that IL‐2 inhibition of progenitor cell proliferation depends on the expression of the TAC antigen, which can be regulated by IL‐1.
Pharmacological characteristics of diazepam receptors in neurons and astrocytes in primary cultures
Authors: Bender A. S. , Hertz L. 
Published: January 2005

AbstractBenzodiazepine binding sites in mouse astrocytes and neurons in primary cultures were labeled with [3H]diazepam (1.8nM), and 3 benzodiazekpine antagonists was studied. RO 5‐4864, RO 7‐3351, and, especially, the antagonist PK 11195 were much more potent in astrocytes than in neurons, whereas the opposite was true for the agonists alprazolam, clonazepam, flurazepam, RO 11‐3128, and chlordiazepoxide, and, especially, the antagonists CGS‐8216 and RO 15‐1788. Flunitrazepam, diazepam, midazolam, RO 11‐6893, and RO 5‐2181 were about equipotent in the two cell types. The neuronal, but not the astrocytic, binding site showed stereospecificity. In astrocytes most of the drugs had pseudo‐Hill coefficients close to one, whereas thepseudo‐Hill coefficients in neurons, except for RO 5‐4864 and PK 11195, were distintly lower than one. Thus, the benzodiazepine binding sites had profoundly different pharmacological characteristics in neurons and in astrocytes.
Nerve growth factor immunoreactivity in mouse kidney: An immunoelectron microscopic study
Authors: Barajas L. , Salido E. C. , Laborde N. P. , Fisher D. A. 
Published: January 2005

AbstractWe have recently reported the immunolocalization of nerve growth factor (NGF) in mouse kidney by light microscopy. In the present study, we have investigated the ultrastructural localization of NGF by the preembedding immunoperoxidase method for electron microscopy. NGF immunoreactivity was present in the connecting tubule cells of the distal nephron. These cells showed immunostaining associated with the Golgi complex, vesicles, rough endoplasmic reticulum (RER), and polyribosomes. The intercalated cells, in contrast, lacked immunoreactivity.
Ganglioside interactions with the dopaminergic system of rats
Authors: Tilson H. A. , Harry G. J. , Nanry K. , Hudson P. M. , Hong J. S. 
Published: January 2005

AbstractThe effects of ganglioside treatment on changes in dopaminergic funciton following 6‐hydroxydopamine (6‐OHDA) or repeated exposure to haloperidol were studied in male Fischer‐344 rats.Rats were injected sc with 30 mg/kg of a mixed ganglioside preparation (GM) at the time of the surgery and for 13 days after receiving an intranigral injection of 6‐OHDA. GM treatment attenuated 6‐OHDA depletion of striatal dopameine (DA) and DOPAC. Another group of rats was implanted with chronic indwelling cannulas in the lateral cerebroventricles at the time of 6‐OHDA administration into the substantia nigra. Daily intraventricular injection of 25 or 50 μg GM attenuated depletions of striatal DA and DOPAC. A separate experiment sought to determine the effects of GMI on the development of receptor supersensitivity produced by repeated exposure to a dopamine receptor antagonist, rats were injected sc with 1 mg/kg haloperidol for 8 or for 16 days; some rats were coadministered 2 mg/kg GMI sc. Four days after the last dose, the rats were challenged with 1 mg/kg apomorphine, and activity was counted for 6 min. Treatment with GMI decreased the behavioral supersensitivity to apomorphine induced by repeated exposure to haloperido. Theses experiments suggest that treatment with GM can have a protective effect against 6‐OHDA‐induced depletion of dopamine if treatment with GM begins at the time of lesioning. These studies also support receptor binding data from other laboraories indicating that treatment with GM1 can affect up‐regulation of dopamine receptors.
Kinetic and pharmacologic characterization of dopamine binding in the mouse cerebellum and the effects of the reeler mutation
Authors: Panagopoulos N. , Matsokis N. A. , Valcana T. 
Published: January 2005

AbstractThe purpose of this study was to characterize the dopaminergic system in the mouse cerebellum and to determine whether the dyskinesia of the reeler mutant is accompanied by alterations in cerebellar and/or striatal dopamine binding. From the analysis of (3H) dopamine ((3H) DA) and (3H)spiperone ((3H)Sp) binding, and the comparison of these parameters between the cerebellum and striatum, we conclude that an dopaminergic system exists in the cerebellum with properties common to the striatal system but also with some differences. That is, (1) with (3H)DA as ligand, we find two binding sites in cerebellum with similar Kd to those of striatum but of lower density, (2) with (3H)Sp as ligand we observe two binding sites in cerebellum and one in striatum, and (3) the competition of (3H)DA binding by various drugs shows that among the cerebellar sites, relative to striatum, there is a higher proportion that corresponds to high affinity D3 and D4(D2 high) binding sites. In cerebellum and striatum of reeler mice, (3H) binding increases 125–174% and 14%, respectively.
Effect of epidermal growth factor and insulin on DNA, RNA, and cytoskeletal protein labeling in primary rat astroglial cell cultures
Authors: Avola R. , Condorelli D. F. , Surrentino S. , Turpeenoja L. , Costa A. , Stella A. M. Giuffrida 
Published: January 2005

AbstractThe effect of epidermal growth factor (EGF) and insulin on DNA, RNA, and cytoskeletal protein labeling in primary rat astroglial cell cultures was investigated. Cultures were grown for 15–30 days in vitro in 10% fetal calf serum (FCS)‐supplemented medium and then maintained in serum‐free basal medium (DMEM) supplemented with fatty acid‐free bovine serum albumin (BSA) for a starvation period of 24 hr before the addition of factors. The effect of factors was tested at different times (4, 10, 22, and 28 hr). At each time, [methyl‐3H]thymidine or [5, 6 ‐3H]uridine was added to the control and treated cells; the incubation time after the addition of labeled precursors was 2 hr at 37°C. The results obtained indicated that the addition of EGF or FCS significantly stimulated [methyl‐3H]thymidine incorporation into DNA, reaching the maximum effect after 22 hr. EGF alone significantly stimulated [3H]uridine incorporation into RNA, and this effect was already maximum at 4 hr and remained constant up to 22 hr.The addition of insulin alone caused a slight increase in nucleic acid labeling for short times (4–10 hr). In contrast with EGF, no detectable stimulation of incorporation of labeled precursors after insulin treatment for 22 hr was observed. On the other hand, the addition of insulin in the presence of EGF induced an increase of the values observed with EGF alone on macromolecular synthesis at all the times studied.Furthermore, a decrease in cell number was observed in confluent cultures maintained for 1 week in medium containing DMEM + BSA in comparison to serum‐supplemented (DMEM + BSA + FCS) cultures. The addition of EGF to DMEM + BSA significantly increased cell number, while addition of insulin had no effect. The highest values for cell number were observed when insulin and transferrin were added together with EGF. Moreover, EGF treatment in the presence of serum significantly increased the incorporation of labeled amino acids into vimentin, glial fibrillary acidic protein, and actin.
Glutamate and kainate effects on the noradrenergic neurons innervating the rat vas deferens
Authors: Lara H. , Bastos‐Ramos W. 
Published: January 2005

AbstractThe effects of glutamate on the noradrenergic innervation of the rat vas deferens have been investigated. Administration of a single dose of kainate (50μg) to the peripheral noradrenergic ganglia innervating the vas deferens induced a time‐dependent decrease of norepinephrine in the organ; after 10 days the norepinephrine concentration had fallen to 35% of control values. This effect was accompanied by a 70% decrease in the potassium‐induced release of recently incorporated 3H‐norepinephrine. Concomitantly, post‐synaptic hypersensitivity to both norepinephrine and dopamine appeared. The finding that adrenergic ganglia possess high‐affinity glutamate binding sites suggests that the effect of kainate may be ascribed to glutamate receptors present on the perikarya of the noradrenergic neurons. It is concluded that noradrenergic neurons of the vas deferens are under glutamatergic control and that this might be important in the motor control of the organ.
Purification and partial characterization of brain adenosine deaminase: Inhibition by purine compounds and by drugs
Authors: Centelles J. J. , Franco R. , Bozal J. 
Published: January 2005

AbstractRat brain adenosine deaminase (E. C. 3.5.4.4.) was purified 667‐fold from the supernatant fraction by the following techniques: heat treatment (60°C), fraction‐ation with ammonium sulfate, column chromatography on DEAE‐Sepharose, and preparative gel electrophoresis. The purified enzyme was homogeneous by the criterion of polyacrylamide disc gel electrophoresis and isoelectric focusing. Amino acid composition is given. The isoelectric point of the enzyme (5.2) was determined by isoelectric focusing on agarose. The apparent molecular weight was estimated to be 39,000 (Stokes Radius [Rs] = 27.3 Å) using a calibrated Sephacryl S‐300 column. The study of the influence of the temperature on the initial reaction rates allowed calculation of Ea (8.9 Kcal/mole) and ΔH (5.0 Kcal/mole) values. The variation of V and Km with pH suggests the existence of a sulfhydryl group and an imidazole group in the enzyme‐substrate complex. The enzyme had a Km (adenosine) of 4.5 × 10−5 M and was inhibited by inosine, guanosine, adenine, and hypoxanthine but not by other intermediates of purine metabolism. None of the inhibitors were active as substrates. The enzyme was also inhibited by dimethyl sulfoxide and ethanol. Inhibition by ethanol can account partially for the CNS depressant effects of levels 3 and 4 of alcohol intoxication. A number of drugs having therapeutic uses such as sedative, anxiolytic, analgesic, and relaxant are modulators of the enzyme. Among these, lidoflazine, phenylbutazone, and chlordiazepoxide are the most potent as inhibitors (Ki 30, 54, and 83 μM, respectively), whereas medazepam is the most potent as activator (Ka 0.32 mM). Thus, it is concluded that some drugs that inhibit adenosine uptake also modulate adenosine deaminase activity. Besides, since the enzyme is located extracellularly [Franco et al, 1986], these drugs can modulate the physiological effects exerted by extracellular adenosine.
Rat interferon enhances the expression of acetycholine receptors in rat myotubes in culture
Authors: André P. , Braun S. , Passaquin A. C. , Coupin G. , Bartholeyns J. , Warter J. M. , Poindron P. 
Published: January 2005

AbstractInterferon enhances α‐bungarotoxin binding on 5‐day‐old rat myotubes. The increase is time‐ and dose‐dependent. KD for bungarotoxin remains unchanged in the presence and in the absence of interferon, while the maximum number of binding sites is dramatically affected by interferon. Cycloheximide inhibits the effect of interferon, which suggests that the enhancement of α‐bungarotoxin binding depends on protein synthesis.
Enhanced expression of a protein antigen (JI‐31 antigen, 30 kilodaltons) by reactive astrocytes in lacerated spinal cord
Authors: Predy R. , Malhotra S. K. , Das G. D. 
Published: January 2005

AbstractA mouse monoclonal antibody IMAb JI‐31, isotype IgG 2b was raised against an autopsy sample of cerebral white matter from a multiple sclerosis (MS) patient. MAb JI‐31 recognizes a protein (JI‐31 antigen) in human brain which has a molecular weight of approximately 30,000 daltons (30 kD) as determined by immunoprecipitaion followed by SDS‐gel electrophoresis (reducing conditions) and autoradiography (Singh et al.: Biosci Rep 6:73–79,1986). By immunofluorescence micoroscopy,. Mab JI‐31 stains glial fibrillary acidic protein (GFAP)‐positive cells, namely astrocytes from GFAP (Predy et al.:Biosci Rep 7:491–502,1987).In this paper we report we report that greatly enhanced staining for JI‐31 antigen is exhibited by reactive astrocytes which arise following CNS injury. (Laceration‐tape surgical lesion of the rat spinal cord served as the expermental modle.) Enhanced expression of JI‐31 antigen reveals some new aspect of the astrocyte response to injury, involving transformation to the reactive state. Consequently, MAb Jl‐31 may be a useful marker for studies or reactive astrocytes.
Differential outgrowth of retinal neurites on purified extracellular matrix molecules
Authors: Carri N. G. , Perris R. , Johansson S. , Ebendal T. 
Published: January 2005

AbstractOrganotgpic cultures of the embryonic retina were system. Microexplants from the chick retina (embryonic day 6) were grown in medium matrix molecules adsorbed to plastic at various concentrations. The maximum neurite length obtained on each type of substratum was measured on day 4 of vitronectin or a hyaluronate‐binding chondroitin sulmolecules On neurite during containing appropriate trophic On purified fate proteoglycan. In contrast, neurite was strongly promoted on laminin in a dose‐dependent manner. Fibronectin elicited a neurite outgrowth corresponding to about one‐third the length Of the Outgrowth On laminin. A 319000‐dalton fibronectin moted by the intact fibronectin molecule. Other isolated domains Of fibronectin, including the 1059000‐ dalton “cell‐binding” domain, did not allow neurite outgrowth. Furthermore, preincubation of fibronec tin substratum with antibodies to the heparin‐binding to fragment elicited neurite elongation the heParin‐binding fibronectin fragment entirely Prevented outgrowth. Fiber Outgrowth was evoked On substrata Of Platelet factor 4, a protein binding heparan Adding increasing concentrations of heparin Progressively inhibited the neurite extension on laminin, whereas similar addition of soluble chondroitin sulfate Proteogbcan had no effect. The results indicate that growing retinal neurites show strong preference for indicate that laminin versus fibronectin. Moreover, the outgrowth‐ to be localized to their heparin‐binding regions. It is tern, elongating retinal neurites can actively discriminate between different extracellular molecules by a mechanism that may involve participation of cell surface heparan sulfate proteoglycans.
Isolation and nucleotide sequence of a cDNA clone encoding bovine adrenal tyrosine hydroxylase: Comparative analysis of tyrosine hydroxylase gene products
Authors: D'Mello S. R. , Weisberg E. P. , Stachowiak M. K. , Turzai L. M. , Gioio A. E. , Kaplan B. B. 
Published: January 2005

AbstractInvestigations into the structure and mechanisms regulating the expression of the genes involved in cate cholamine biosynthesis have led to the isolation of a cDNA coding for bovine adrenal tyrosine hydroxylase (TH). The 1,722 bp cDNA contains the complete coding sequence and 3′ untranslated region of the TH mRNA. The nucleotide sequence of the cDNA and the deduced amino acid sequence were compared to those reported for rat and human TH. Bovine TH shares 85% and 84% amino acid sequence identity with that of rat and human TH, respectively. Alignment of the amino acid sequences of rat, bovine, and human TH reveals that 79% of the residues are identical in all three species, indicating a strong evolutionary conservation of enzyme structure. Moreover, three of the four putative phosphorylation sites located in the N‐terminal region of TH are conserved in these animal species. There are, however, some interspecies differences in TH gene products. The 3′ untranslated region of bovine TH mRNA is 56 and 97 nucleotides shorter than rat and human TH mRNA, respectively. Additionally, the bovine protein is 7 and 6 amino acids smaller than its rat and human homologues. All of the absent amino acid residues of bovine TH are missing from an alanine‐rich region in the N‐terminal portion of the rat and human proteins (amino acids 51‐68). Comparison of the size of bovine and rat TH mRNA and protein by northern blot and immunoblot analyses yielded differences consistent with those predicted from the nucleotide sequence data.
Human γ enolase: Isolation of a cDNA clone and expression in normal and tumor tissues of human origin
Authors: Van Obberghen E. , Kamholz J. , Bishop J. G. , Zomzely‐Neurath C. , Lazzarini R. A. 
Published: January 2005

AbstractWe have isolated and sequenced a cDNA clone encod‐ ing the human γ enolase. Comparison of our cDNA sequence and the rat γ enolase sequence revealed 97% homology at the level of amino acid sequence. The two coding regions were 91% homologous on the nu‐ cleotide level, whereas the 3′ noncoding regions were much less homologous (32%). Further comparison of our cDNA sequence with the human a enolase re‐ vealed an 82% homology at the amino acid level and a 75% homology at the nucleotide level for the two coding regions, whereas the 3′ nontranslated regions were only 30% homologous. Using a portion of the 3′ nontranslated region of our cDNA, shown to be spe‐ cific for human γ enolase, a single 2.5 kb mRNA was detected in human brain tissue. This same γ enolase message was also found in a number of human normal nonneuronal tissues, and in several human tumor‐ derived cell lines. Expression of the mRNA for the γ enolase subunit should thus be used with caution when identifying the cells of neuronal or neuroendocrine origin.
Inhibition of K+ permeability diminishes alpha2‐adrenoceptor mediated effects on norepinephrine release
Authors: Zimanyi I. , Folly G. , Vizi E. S. 
Published: January 2005

AbstractThe effect of two different potassium channel blockers, 4‐aminopyridine (4‐AP) and quinine, on the alpha2‐adrenoceptor mediated modulation of norepinephrine (NE) release was investigated. Pairs of mouse vasa deferentia were loaded with 3H‐norepinephrine (3H‐NE), superfused continuously, and stimulated electrically. 4‐AP (5.3 × 10−4 M), and quinine (10−5 M) enhanced the stimulation‐evoked release of tritium significantly. The electrically induced release of radioactivity was reduced by alpha2‐adrenoceptor agonists (1‐NE and xylazine) and enhanced by the alpha2‐adrenoceptor antagonist yohimbine. Both effects were affected markedly by 4‐AP or quinine: the depressant action of 1‐NA and xylazine was partially antagonized and the facilitatory effect of yohimbine was completely abolished during the blockade of the potassium channels. It is suggested that the blockade of potassium permeability counteracts negative feedback modulation; therefore, it seems likely that the stimulation of alpha2‐adrenoceptors leads to an enhanced potassium permeability and hyperpolarization of varicose axon terminals.