bluuebunny/crossref_metadata_2025 huggingface dataset:
The girl, nature, goddess, or how Marilyn Monroe became ‘the queen of glamour’?
Authors: Łuksza Agata
Published: March 2018

‘Did you ever see anything like her?’, Cleveland Amory asked Hedda Hopper while they were both watching the making of the famous ‘bathtub scene’ in The Seven Year Itch (Wilder, 1955). How can one explain the phenomenon of Marilyn Monroe – the ‘queen of glamour’, as her contemporaries called her? This research examines the case of Marilyn Monroe with reference to the model of glamorous femininity which has emerged in modern consumer societies. Monroe is understood as a ‘representative character’, not a real person, and the study aims at reconstructing and deconstructing her public image, not at establishing the ‘truth’ about her personal life. The most influential components of Monroe’s persona are indicated and analysed based on press material from her lifetime and her repertoire, i.e. the pin-up context, the association with nature and the ‘goddess’ aspect. It is maintained that these components accounted for Monroe’s lasting status as an icon of glamour but also best corresponded to the changes in morality and sexuality that American society experienced in the 1950s.
Lyric images, everlasting instants: The photographic works of Tacita Dean and Roni Horn
Authors: Thornton Becca
Published: March 2018

Of the most recent turn to literary practices in contemporary art, this article studies one facet: that which relates to the lyric tradition. It hopes to make a case for ‘lyric images’, drawing on the works by artists Tacita Dean, Day for Night (2009), and Roni Horn, Still Water [...] (1999). Read around poems by Emily Dickinson, John Fuller and Margaret Atwood, how these artworks utilize photography’s natural capacity to mirror both the recursive syntactic structure and the blending of instantaneity with immortality common to the lyric poem is explored. Particularly, the article considers notions of cyclical seriality – as composed of singular moments, yet tending towards the infinite – both formally and referentially. Whether these qualities provoke an imaginative and/or emotive looking that contrasts with our response to previous assumptions of the written form in conceptual art practices (e.g. Art and Language) is also reflected upon, in order to contemplate why this particular hybridising may be current in photographic practice.
Aberrant flight paths: The uncertain bearings of Malaysian Airlines f﻿light MH370
Authors: Simmons Matthew
Published: March 2018

This article examines the disappearance of Malaysian Airlines MH370 through the lens of its varied non-human witnesses. By employing Harun Farocki’s notion of operative images in conjunction with the process philosophy of Alfred North Whitehead it plots a radically dispersed and autonomous image-making apparatus that captured the event of the aircraft’s disappearance and accelerated the expansion of the event itself. Crucially, this article proposes that these images cannot be understood in terms of vision but must be read instead as a series of tactile or synaesthetic practices between materials. Through examining contemporary image-making technologies employed in the search for the aircraft, it charts an ontological tactility within image making, one that – it is argued – has been present since the birth of the medium itself.
Reinventing the body on the photographic stage: Theatricality, identity, and figural writing in the work of Helena Almeida
Authors: Duarte Miguel Mesquita , Marques Bruno
Published: March 2018

The fictional regime of the photographic image allows Helena Almeida to stage a theatrical metamorphosis of her own body through displacements, expansions and dissimulations, placing photography at the heart of a pictorial transgression that undermines the disciplinary boundaries of visual media: the artist becomes ink, inhabits the empty canvas space, multiplies herself in mirror games that produce the unfolding of a body in deep crisis, thrown beyond its physical limits and identity. Moreover, in multimedia works such as Feel me, Hear me and See me (1979–1980), as well as in some images of the series entitled The House (1982–1983), Almeida seems to move towards a radical linguistic and pictorial derangement, likely to break the traditional communicative and representative mechanisms. We seek to demonstrate, on the basis of these different aspects relating to photography’s effects of hybridization, and making use of the post-structuralist thought of Jacques Derrida and Gilles Deleuze, that the artist moves towards the designation of a structural space that combines photography, writing and the reinvention of the body. Almeida’s work confronts us with a complex reconfiguration of ways of seeing, feeling and thinking the photographic act, as well as its discursive features.
Mídia, raça e a construção do suspeito
Authors: Giorgi Maria Cristina , Sampaio de Almeida Fabio , Silva Paiva Maria Vitória
Published: March 2018

O presente artigo tem por objetivo refletir, desde uma visão enunciativa de linguagem (MAINGUENEAU, 2013) e de seu viés de intervenção (ROCHA, 2006; 2014), acerca da produção discursiva do processo de suspeição da pessoa negra e de sua condução à condição de “fora de lugar”, a partir de construções discursivas que a mídia tem feito desta população em diálogo com discursos que circulam em outras esferas como a das práticas policiais e da justiça. Partimos de compreensão da linguagem como prática social (BAKHTIN, 1995; 1997) que, situada sociohistoricamente e atravessada por relações de saber e poder (FOUCAULT, 2013; 2013a), não apenas representa, mas intervém em uma dada realidade. Com relação à questão racial, entendemos como Guimarães (2006; 2009), que esse processo resulta da colonização que expropriou o africano de sua humanidade e é reforçado nos discursos que visam a manter os privilégios do grupo hegemônico. Para tal, dialogando com pesquisa realizada por Paiva (2015), no acervo do jornal Folha de São Paulo, procedemos a uma análise discursiva de notícia selecionada. Os resultados indicam que, em nome da neutralidade e imparcialidade que tende a ser vista como característica do gênero notícia, ao apresentar os fatos, o jornal constrói e reafirma, seu posicionamento político alinhado a discursos hegemônicos enunciados por grupos dominantes.
Comparing health risk behaviors of Franklin County youth with their national and statewide counterparts: An ecological study in the state of Kentucky
Authors: Walston Herman , Meshack Angela , Latham Timothy , Peters III Ronald , Gans Timothy , Peters Anthony , Majid Warith
Published: March 2018

While national surveillance studies have stratified high school studentsâ€™ health behavior outcomes, few ecological data sets have been explored, collected, and analyzed on the unique health problems of minority children. An area for which limited data on minority youth has been collected is Franklin County, home of the state capital of Kentucky. In the current study, we use baseline data collected in 2015 from students attending two high schools that were sites for Kentucky State Universityâ€™s Youth Empowerment Project. We hypothesize that youth who reside in Franklin County would report lower maladjusted behaviors than their national and statewide counterparts in the same year of observation. Data analyses confirm that compared to their national- and state-level counterparts, Franklin County high school students were less likely to report riding with a driver who had been drinking alcohol, engaging in sexual intercourse, drinking alcohol before sexual intercourse, and experiencing non-condom use when engaged in sexual intercourse, forced sexual intercourse, dating violence, cyber bullying, suicidal ideation, and drug use. These findings suggest that Franklin County high school students may be exposed to environmental variables that may be preventive to maladjusted behaviors.
Crystal structure of bis(μ-N-i-propyl-N-n-propyldithiocarbamato-κ3
S,S′:S)bis(N-i-propyl-N-n-propyldithiocarbamato-κ2
S,S′)dicadmium(II), C28H56Cd2N4S8
Authors: Tan Yee Seng , Tiekink Edward R.T.
Published: March 2018

C28H56Cd2N4S8, monoclinic, P21/n (no. 14), a = 9.9003(3) Å, b = 11.7373(3) Å, c = 17.4539(5) Å, β = 102.999(3)°, V = 1976.22(10) Å3, Z = 2, R
gt(F) = 0.0243, wR
ref(F
2) = 0.0582, T = 100 K.
Synthesis and crystal structure of bis(μ2-acetato-κ2
O:O′)-di(ethanol)-bis{μ2-5-(N,N′-diethylamine)-5′-methoxyl-2,2′-[ethylenediyldioxybis(nitrilomethylidyne)]diphenolato-κ6
O:O,N,N,O′:O′}trinickel(II) – ethanol – acetonitrile (1/2/2), C58H86Ni3N8O18
Authors: Zong-Li Ren , Xiao-Xin An , Ling-Zhi Liu , Peng-Fei Lan , Wen-Kui Dong
Published: March 2018

C58H86Ni3N8O18, triclinic, P1̅ (no. 2), a = 11.4561(8) Å, b = 13.1859(8) Å, c = 13.5063(11) Å, α = 109.620(7)°, β = 101.234(7)°, γ = 114.469(6)°, V = 1611.1(2) Å3, Z = 1, R
gt(F) = 0.0518, wR
ref(F
2) = 0.1315, T = 173.69(10) K.
Crystal structure of N-(3-chlorophenyl)ethoxycarbothioamide, C9H10ClNOS
Authors: Tan Yee Seng , Yeo Chien Ing , Tiekink Edward R.T.
Published: March 2018

C9H10ClNOS, monoclinic, C2/c (no. 15), a = 18.8783(6) Å, b = 4.5518(2) Å, c = 23.6739(8) Å, β = 91.501(4)°, V = 2033.61(13) Å3, Z = 8, R
gt(F) = 0.033, wR
ref(F
2) = 0.082, T = 100(2) K.
The immunocytochemical localization of tyrosine hydroxylase within rat sympathetic neurons that release acetylcholine in culture
Authors: Higgins D , Iacovitti L , Joh TH , Burton H
Published: March 2018

In vitro populations of neurons dissociated from the superior cervical ganglion of the rat embryo can acquire many of the properties of cholinergic neurons and yet retain some of the characteristics of adrenergic neurons. To determine whether one neuron can stably express properties of two transmitter systems, identified neurons were characterized by both immunocytochemical and electrophysiological methods. It was found that more than 90% of the neurons that formed functional cholinergic synapses had tyrosine hydroxylase within their cytoplasm. Furthermore, this mixed phenotypic expression persisted for more than 1 month. It is concluded that, under certain conditions in vitro, most neurons from the superior cervical ganglion have at least the potential for dual function.
Glycinergic pathways in the goldfish retina
Authors: Marc RE , Lam DM
Published: March 2018

Autoradiographic localization of high affinity [3H]glycine uptake in the retina of the goldfish has been used to study some anatomical and physiological properties of potentially glycinergic neurons. There are two classes of retinal cells exhibiting high affinity glycine uptake: Aa amacrine cells and I2 interplexiform cells. Aa amacrine cells constitute about 20% of the somas in the amacrine cell layer and send their dendrites to the middle of the inner plexiform layer. There they are both pre- and postsynaptic primarily to other amacrine cells. Photic modulation of glycine uptake indicates that they are probably red-hyperpolarizing/green-depolarizing neurons. I2 interplexiform cells are a newly discovered type of interplexiform cell; in the outer plexiform layer, they receive direct synaptic input from the somas of red-dominated GABAergic H1 horizontal cells and are apparently presynaptic to dendrites of unidentified types of horizontal cells. The connections of I2 interplexiform cells have not been successfully characterized in the inner plexiform layer. These findings extend our knowledge of neurochemically specific pathways in the cyprinid retina and indicate that glycine, like GABA, is a neurotransmitter primarily involved with circuits coding “red” information.
Autoradiographic localization of muscarinic cholinergic receptors in rat brainstem
Authors: Wamsley JK , Lewis MS , Young WS , Kuhar MJ
Published: March 2018

We have localized muscarinic cholinergic receptors in the rat brainstem by a light microscopic autoradiographic method. Initially, we examined the kinetics and specificity of the binding of radiolabeled quinuclidinyl benzilate ([3H]QNB) in slide-mounted, frozen tissue sections to determine that we were labeling the muscarinic cholinergic receptors as they had been described previously in biochemical pharmacological studies. Subsequently, using optimal binding parameters to obtain high specific to nonspecific ratios, we labeled tissue sections and generated autoradiograms by the apposition of emulsion- coated coverslips. We found high concentrations of autoradiographic grains associated with many nuclei in the brainstem including the superior colliculus, nuclei of the lateral lemniscus, pontine nucleus, parabrachial nucleus, trigeminal nerve nucleus (V), the tegmental nuclei, nucleus of the facial nerve (VII), the locus coeruleus, the medial vestibular nucleus, cochlear nucleus, of the tractus solitarius, and nucleus of the hypoglossal nerve (XII). We conclude that muscarinic cholinergic effects of acetylcholine and important in the normal function of both the sensory and motor systems. We speculate on the possible mechanisms of action of certain cholinergic agents, such as the mechanism of anticholinergic compounds when used to treat motion sickness or anticholinesterase poisoning.
Neurotransmitter- and neuromodulator-dependent alterations in phosphorylation of protein I in slices of rat facial nucleus
Authors: Dolphin AC , Greengard P
Published: March 2018

Protein I is a neuronal phosphoprotein associated primarily with synaptic vesicles. Regulation of its state of phosphorylation has been investigated in slices of rat facial nucleus. This brainstem motor nucleus has a facilitatory serotonergic input and contains no interneurons. Serotonin (5-hydroxytryptamine, 5-HT, 10(-4) M), in the presence of the phosphodiesterase inhibitor isobutylmethylxanthine (IBMX, 4 x 10(-5) M), converted approximately 26% of Protein I in these slices from the dephospho-form to the phospho-form. This effect was partially inhibited using two classical 5-HT antagonists, mianserin added to the slices during in vitro incubation and metergoline administered in vivo. The effect of 5-HT appeared to be Ca2+-dependent, unlike that of IBMX (10(-3) M). Adenosine, its analog 2- chloroadenosine, and ATP also increased the phosphorylation of Protein I in facial nucleus slices. 2-Chloroadenosine (5 x 10(-4) M) caused a 29% phosphorylation of Protein I, and this effect was not dependent on extracellular Ca2+. The phosphorylation of Protein I caused both by 2- chloroadenosine and by ATP was inhibited by the adenosine antagonist 2′- deoxyadenosine. Results of additional experiments suggest that the great majority of the Protein I in the facial nucleus is present in presynaptic terminals other than the serotonergic afferents. It is concluded that the stimulation by 5-HT and adenosine of Protein I phosphorylation results largely from a direct action of these compounds on those Protein I-containing terminals.
Cercal sensory development following laser microlesions of embryonic apical cells in Acheta domesticus
Authors: Edwards JS , Chen SW , Berns MW
Published: March 2018

The hypothesis that pioneer fibers, which develop relatively early in the differentiation of insect appendages, serve to organize the peripheral sensory nerves was tested by ablating apical regions of the cercal rudiments in embryos of Acheta domesticus. Multiple nerve bundles rather than the normal middorsal and midventral pair of nerves were formed within the cercus following ablation of the cercal tip before pioneer fiber differentiation, but the cercal nerve was normal when lesions were made after formation of the pioneer fiber tracts and associated glia. These results indicate a necessary morphogenetic role for the pioneer fibers.
Metabolic effects of unilateral lesion of the substantia nigra
Authors: Wooten GF , Collins RC
Published: March 2018

Regional brain glucose utilization following unilateral lesion of the substantia nigra in rat was studied by [14C]-2-deoxyglucose autoradiography. Substantia nigra lesions were performed by perinigral injections of 6-hydroxydopamine (6-OHDA) . HBr, 6 microgram, in rats pretreated 30 min earlier with desmethylimipramine (DMI), 25 mg/kg, subcutaneously. The lesion produced extensive destruction of the ipsilateral substantia nigra pars compacta and a greater than 99% reduction in dopamine concentration in the ipsilateral striatum. Pretreatment with DMI prevented any reduction in the concentration of norepinephrine in ipsilateral forebrain structures. Glucose utilization was increased in the ipsilateral globus pallidus at 11, 21, 53, and 104 days after substantia nigra lesion with the largest increase (about 140% of control) occurring at 21 days post-lesion. In addition, glucose utilization in ipsilateral lateral habenular nucleus was increased at each of the above time points. No changes in glucose utilization were noted in frontal cortex, striatum, subthalamic nucleus, entopeduncularis, or ventral tier nuclei of the thalamus. These results suggest that lesion of the substantia nigra with depletion of striatal dopamine content results in disinhibition of some striatal, and perhaps olfactory cortical, efferents producing increased metabolism and glucose utilization in terminal fields within the globus pallidus and lateral habenular nucleus.
Local circuit synaptic interactions in hippocampal brain slices
Authors: Knowles WD , Schwartzkroin PA
Published: March 2018

The hypothesis that recurrent inhibition in the hippocampus is mediated by interneurons was tested with simultaneous intracellular recordings from the CA1 region of guinea pig hippocampal slices in vitro. In recordings from 101 pairs of pyramidal cells, no interactions were detected in 87% of the pairs. In 13% of the pyramidal cell pairs, spike trains induced in one cell caused inhibitor postsynaptic potentials (IPSPs) in the second cell. No excitatory interactions were detected. In recordings from 43 pairs of cells, where one cell was a pyramidal cell and the other cell was an interneuron, no interactions were detected in 53% of the pairs. In 30% of the interneuron-pyramidal cell pairs, spike trains elicited from the interneuron caused IPSPs in the pyramidal cell. In 28% of the pairs, spike trains elicited from the pyramidal cell caused excitatory postsynaptic potentials (EPSPs) in the interneurons. In 4% of these pairs, reciprocal interactions were seen, with the pyramidal cell exciting the interneuron and the interneuron inhibiting the pyramidal cell. These results support the hypothesis that inhibitory mediate recurrent inhibition in the hippocampus. However, the data also suggest that the interneurons from which these results were recorded were a subset of inhibitory interneurons distinct from the classical basket cell. These interneurons may mediate both feed-forward and recurrent inhibition in the hippocampus.
On the role of cyclic nucleotides in the transmitter choice made by cultured sympathetic neurons
Authors: Walicke PA , Patterson PH
Published: March 2018

Previous investigations have established that electrical activity or chronic depolarization influences the development of neonatal rat sympathetic neurons in dissociated cell culture. Depolarization reduces their ability to respond to a cholinergic inducing factor produced by non-neuronal cells, allowing normal adrenergic differentiation to proceed (Walicke, P., R. Campenot, and P. Patterson (1977) Proc. Natl. Acad. Sci. U. S. A. 74: 5767–5771). The present study examines whether the developmental effects of depolarization are mediated through cyclic nucleotides. Addition of dibutyryl cAMP, dibutyryl cGMP, adenosine, prostaglandin E1, and cholera toxin all raise neuronal cyclic nucleotide levels and qualitatively mimic the developmental effects of depolarization. However, the quantitative decrease in acetylcholine production caused by these cyclic nucleotide agents is much smaller than that caused by depolarization. Short (48-hr) exposures to the cyclic nucleotide derivatives do not alter transmitter synthesis, indicating that long term developmental changes are involved. Chronic depolarization with elevated K+ increases neuronal cAMP 2-fold but has little effect on cGMP. The increase in cAMP is maintained during several weeks of depolarization and is present as early as the 3rd day in vitro, preceding the significant alterations in adrenergic and cholinergic differentiation. Exposure to 2 mM theophylline also increases neuronal cAMP, but in contrast to the other agents, it enhances cholinergic differentiation. In combination with elevated Ktheophylline further increases neuronal cAMP but still favors cholinergic differentiation. Thus, although cAMP satisfies some criteria for being the second messenger in the developmental effects of depolarization, several findings are consistent with the nucleotide playing a central role: (i) Depolarization has much larger effects on transmitter choice than the cyclic nucleotide agents and (ii) theophylline can uncouple cyclic nucleotide levels from the developmental events.
Two components from eye tissue that differentially stimulate the growth and development of ciliary ganglion neurons in cell culture
Authors: Nishi R , Berg DK
Published: March 2018

Survival and development of chick ciliary ganglion neurons in vivo appear to depend on information from the embryonic eye structure that contains the postsynaptic targets of the neurons. We have tested embryonic eye extracts on ciliary ganglion neurons in dissociated cell culture for stimulation of growth and development. Control conditions were chosen that permitted the long term maintenance of the neurons in the absence of tissue extracts of conditioned medium. The conditions included coating the culture substratum with fibroblast material and increasing the K+ concentration in the culture medium to 25 mM. Neurons survived for at least 3 weeks in control conditions. Two major components were resolved in eye extracts that stimulated growth and development of the neurons above the basal levels obtained with control conditions. One component, with an apparent molecular weight of about 2 X 10(4) by gel filtration analysis, stimulated neuronal growth without increasing the levels of choline acetyltransferase activity per neuron. The second component, with an apparent molecular weight of about 5 X 10(4), increased development of choline acetyltransferase levels per neuron but had no effect on neuronal growth. Both components were effective in normal K+ as well as 25 mM K+. These components may represent mechanisms by which the postsynaptic target tissue acts in vivo to direct the growth and development of ciliary ganglion neurons.
Sequential inhibition of sexual receptivity by progesterone is prevented by a protein synthesis inhibitor and is not causally related to decreased levels of hypothalamic progestin receptors in the female rat
Authors: Parsons B , McEwen BS
Published: March 2018

In the estrogen-primed ovariectomized female rat, the administration of progesterone facilitates sexual receptivity and activates proceptivity for many hours. If the progesterone dose is large (e.g., 2.5 mg), a refractory period follows, during which time animals are less sensitive to additional progesterone. This refractory period has been termed “sequential inhibition” and has been correlated previously with decreased levels of cytosol progestin receptors in the mediobasal hypothalamus-preoptic area (MBH-POA). Our present results indicate that the “sequential inhibition” of mating behavior by progesterone appears to involve a protein synthetic step that is not related causally to decreased levels of cytosol progestin receptors in the MBH-POA. Animals which received subcutaneous injections of the protein synthesis inhibitor, anisomycin (100 mg/kg in saline), 15 min prior to and again 3 hr after progesterone (2.5 mg in propylene glycol) treatment, displayed greater sexual receptivity at 24 hr than did animals which received subcutaneous saline injections. However, cytosol progestin receptor levels in the MBH-POA of animals which received anisomycin plus progesterone were decreased at 24 hr, relative to animals which received saline plus progesterone. Anisomycin did not produce positive or negative behavioral effects at 24 hr when administered 15 min prior to and again 3 hr after propylene glycol, suggesting that the behavioral effects of anisomycin appear to be related to selective blockade of progesterone action. In separate experiments, we administered single subcutaneous injections of anisomycin at various times relative to progesterone (2.5 mg) treatment. According to the time course of effective anisomycin application, the presumed protein synthesis which is responsible for the inhibition of mating behavior occurs between 3 and 13 hr after the administration of progesterone.
Localization of cholinesterase at sites of high acetylcholine receptor density on embryonic amphibian muscle cells cultured without nerve
Authors: Moody-Corbett F , Cohen MW
Published: March 2018

Myotomal muscle cells, derived from Xenopus embryos and grown in culture without nerve, develop discrete sites of cholinesterase (ChE) activity on their surface. The spatial relationship of these ChE patches to surface patches of acetylcholine receptors (AChRs) has been examined in the present study by a combination of ChE histochemistry and fluorescent staining of the receptors. ChE patches and AChR patches developed as early as the 1st day in culture and exhibited a high incidence of spatial overlap. The frequency of overlap varied with the age of the culture and ranged from 50 to 98% for patches on the lower cell surface (facing the floor of the culture dish) and from 28 to 79% for patches on the upper cell surface. The high incidence of overlap cannot be explained on the basis of a random distribution of patches since both types of patch occupied less than 3% of the cell surface. ChE and AChR patches also developed when cultures were grown in a serum- free medium as well as when cultures were prepared from young embryos in which muscle innervation had not yet begun. At some patches, the surface membrane was invaginated and at these invaginations, there was also a high incidence of overlap between the ChE and AChR stains. It is concluded that the mechanisms involved in the localization of AChRs and ChE on the surface of Xenopus myotomal muscle cells tend to be closely linked and operate even in the absence of innervation, previous contact by nerve, or electrical and contractile activity. Considered together with previous ultrastructural observations, the present findings suggest that these cells develop elaborate postsynaptic-like specializations even in the absence of neural factors.
Glutamate and aspartate binding sites are enriched in synaptic junctions isolated from rat brain
Authors: Foster AC , Mena EE , Fagg GE , Cotman CW
Published: March 2018

The binding of the putative excitatory transmitters glutamate (Glu) and aspartate (Asp) was measured in various subcellular fractions in order to assess their degree of localization in synaptic junctions (SJs). For both ligands, specific binding levels increased in the order, whole particulate membranes--crude mitochondrial pellet membranes (P2)-- synaptic plasma membranes (SPM), and were highly enriched in SJs, with values approximately 9 times greater than the values in whole particulate membranes. The recovery of binding sites in SJs suggested that the majority of sites in SPMs were junctional in nature. Specific binding sites were found also in other subcellular fractions, such as microsomal membranes, “light” SPMs, and mitochondrial membranes. Sodium ions were able to stimulate the specific binding of both ligands (Asp greater than Glu), the magnitude of the effect between subcellular fractions being in the order, whole particulate membranes greater than P2 greater than SPM. This effect was absent in SJs. Calcium and magnesium ions also enhanced the binding (Glu greater than Asp) in the order, whole particulate membranes greater than or equal to P2 greater than or equal to SPM greater than SJ. The results indicate that Glu and Asp binding sites have a specific synaptic localization and support a role for Glu and Asp receptors in synaptic transmission.
Trans-synaptic modulation of histamine H-1 receptor development in rat brain
Authors: Subramanian N , Whitmore WL , Slotkin TA
Published: March 2018

To determine whether neuronal histamine influences development of histamine H-1 receptors in the rat brain, neonates were given diphenhydramine, an H-1 antagonist, daily for the first 21 days of postnatal life. In control rats, specific H-1 binding of [3H]mepyramine in whole brain was low at birth and increased progressively toward adult levels by the end of the 3rd week. Animals treated with diphenhydramine showed marked elevations in binding as early as 4 days postnatally and the differences persisted throughout the experimental period. The increased binding in treated rats was specific to treatment with H-1 antagonists (diphenhydramine, mepyramine) as opposed to an H-2 antagonist (cimetidine); the alteration reflected enhancement of the number of binding sites without a change in Kd, a finding indicative of H-1 receptor supersensitivity. Similar results were seen in the hypothalamus, an area rich in neuronal histaminergic projections. Levels of histamine in the hypothalamus were unaffected by diphenhydramine administration until the end of the 3rd week, at which time, increases were noted. After the loading of the hypothalamus with [3H]histamine, release of label by K+ depolarization in vitro (an indirect index of release from the neuronal histamine pool) was readily obtained at all ages and was unaffected by diphenhydramine administration. Diphenhydramine did not alter histamine levels in brain regions in which most of the histamine is non-neuronal. These studies suggest that, even early in the ontogenesis of histaminergic synapses, a sufficient proportion of releasable histamine is associated with histaminergic neurons to enable trans-synaptic modulation of development of histaminergic H-1 receptors; consequently, blockade of these receptors with diphenhydramine results in supersensitivity even at the earliest stages of development.
Selective retrograde labeling of cholinergic neurons with [3H]choline
Authors: Bagnoli P , Beaudet A , Stella M , Cuenod M
Published: March 2018

Evidence is presented which is consistent with a specific retrograde labeling of cholinergic neurons following [3H]choline application in their zone of termination. [3H]Choline injection in the rat hippocampus leads to perikaryal retrograde labeling in the ipsilateral medial septal nuclease and nucleus of the diagonal band, thus delineating an established cholinergic pathway, while only diffuse presumably anterograde labeling was observed in the lateral septum, the entorhinal cortex, and the opposite hippocampus. After [3H]choline injection in the pigeon visual Wulst, only the ipsilateral thalamic relay, of all inputs, showed similar perikaryal retrograde labeling, an observation supporting the suggestion that at least some thalamo-Wulst neurons are cholinergic.
Ontogenesis of olivocerebellar relationships. I. Studies by intracellular recordings of the multiple innervation of Purkinje cells by climbing fibers in the developing rat cerebellum
Authors: Mariani J , Changeux JP
Published: March 2018

The establishment of the adult innervation of Purkinje cells (PCs) by climbing fibers (CFs) was studied in the cerebellar vermis of the developing rat. Excitatory postsynaptic potentials (EPSPs) evoked in PCs by activation of the climbing fibers (CF-EPSPs) were recorded intracellularly from a total of 310 cells in young rats aged from 3 to 15 postnatal days. The CF system was activated by electrical stimulation of either the inferior olive (IO) nucleus or the region near the fastigial nucleus (juxtafastigial or JF stimulation). A given PC at each age was considered to be innervated by more than one CF when the amplitude of the spontaneous or evoked CF-EPSPs fluctuated in a stepwise manner. On the other hand, innervation of a PC by a single CF was established on the basis of the all-or-none character of CF-EPSPs. Two parameters were followed throughout development, the percentage of multiply innervated PCs and the mean number of steps in the evoked CF- EPSPs. The data presented confirm the transient multiple innervation of PCs by CFS on postnatal days 8 and 9 (Crepel, F., J. Mariani, and N. Delhaye-Bouchaud (1976) J. Neurobiol. 7: 567–578) and strongly suggest its existence at earlier stages (from postnatal day 3). Moreover, it is shown that the multiple innervation was maximal on postnatal day 5 and then decreased until the innervation by a single CF was established on day 15.
Prenatal formation of cortical input and development of cytoarchitectonic compartments in the neostriatum of the rhesus monkey
Authors: Goldman-Rakic PS
Published: March 2018

The timing, hemispheric laterality, and mode of termination of input from the prefrontal association cortex to the neostriatum were studied in fetal and neonatal rhesus monkeys using autoradiography for tracing connections. In addition, the cytological maturation of the neostriatum was examined in Nissl-stained sections from the same and other monkeys of selected prenatal and postnatal ages. A small contingent of corticostriatal axons reaches both the caudate nucleus and the putamen by the 69th embryonic day (E69) of the 165-day gestation period in this species and steadily expands over the next 3 fetal months. Throughout this period, ipsilateral perfrontostriatal connections predominate, and only a small and variable amount of label is detectable over the contralateral neostriatum. A major feature of the developing corticostriatal projection is a transfiguration in the distribution of its terminals: from E69 to E95, cortical terminals are distributed uniformly among neostriatal neurons; beginning around E105, areas of higher and lower grain density begin to emerge until finally, by E133, 250- to 500-micrometers-wide circular and elliptically shaped label- free cores perforate a field of densely labeled cortical terminals as in the neostriatum of the adult monkey (Goldman, P. S., and W. J. H. Nauta (1977) J. Comp. Neurol. 171: 369–386). The cytoarchitectonic composition of the neostriatum also changes during gestation: from E69 through E95, the small postmitotic neurons of the immature neostriatum are packed densely and, for the most part, are distributed homogeneously; by E105, they become segregated into cellular islands consisting of densely packed neurons that are encapsulated by fiber- rich annuli and embedded in a matrix of less densely arrayed neurons. The shape and size of the islands in Nissl-stained sections correspond to label-free cores in autoradiograms of fetuses with cortical injections, while the surrounding annuli and adjacent matrix cells correspond to areas of dense accumulation of label. Thus, the formation of the corticostriatal projection in primates involves a transformation in the distribution of ingrowing terminals synchronized with changes in cellular organization of the neostriatum.
Anatomy and physiology of experimentally produced striped tecta
Authors: Law MI , Constantine-Paton M
Published: March 2018

Transplantation of a third eye primordium to the forebrain region of a frog (Rana pipiens) embryo causes two retinal projections to converge on a single tectal lobe. These projections form stereotyped eye- specific termination bands (Constantine-Paton, M., and M. I. Law (1978) Science 202: 639–641) that are similar to the source-specific stripes found normally in many regions of the mammalian brain. In the present study, we use quantitative analyses of anatomical data and double labeling techniques to demonstrate that induced bands of three-eyed frogs are approximately 200 micrometers wide, that they invariably run in a rostrolateral to caudomedial direction, and that they represent interdigitating synaptic zones which fill the entire superficial neuropil of the dually innervated tectal lobe. This periodic segregation pattern is not seen in the superinnervated diencephalon or in the optic tracts. Morphometric measurements on animals with dually innervated tectal lobes revealed an approximate 30% hyperplasia that was restricted largely to the deeper predominantly cellular tectal layers. Each of the banded retinal projections occupied neuropil volumes that were roughly 50% smaller than the volume occupied by the noncompeting retina of the same animal. Eye-specific segregation was detected with extracellular recording techniques as an ability of one of the two eyes to elicit consistently more and larger action potentials throughout a radial penetration of the superficial tectal neuropil. In several preparations, electrolytic lesions confirmed that physiologically defined positions of eye dominance corresponded to a band from the same eye. Maps of the visual field projections within dually innervated tecta were relatively normal and their orientation was consistent with the initial embryonic orientation of the retinas. Eye laterality, time of arrival, or fasciculation during growth are not responsible for this induced banding. Instead, our results are attributed to two mechanisms that are probably fundamental to neural mapping. These are: differential affinities between retinal and tecta loci which normally align the projection by bringing together appropriate pre- and postsynaptic areas and interactions among retinal ganglion cell fibers. The latter causes axons from physically neighboring retinal ganglion cell bodies to terminate together within the tectum and consequently increases the internal order of map. We propose that these same two mapping mechanisms may be responsible for the afferent segregation found in diverse regions of many vertebrate brains.
The effect of calcium on acetylcholine receptor synthesis
Authors: McManaman JL , Blosser JC , Appel SH
Published: March 2018

The level of cytoplasmic calcium has been proposed to act as a regulator of acetylcholine receptor synthesis (Betz, H., and J. P. Changeaux (1979) Nature 278: 749–751). However, there is little known about the effect of altered calcium levels on the metabolism of the acetylcholine receptor. We have investigated the effect of decreased extracellular calcium on the metabolism of acetylcholine receptors in cultured rat myotubes. Our results show that the acetylcholine receptor levels on the surface of myotubes were decreased 25 to 30% following overnight incubation in calcium-deficient medium. In contrast, creatine phosphokinase activity levels and total protein synthesis were unaffected. Calcium depletion did not change the rate of receptor degradation significantly (0.037 hr-1, compared to 0.033 hr-1 for control cells) but dramatically decreased the rate of incorporation of new acetylcholine receptors into the plasma membrane. The time course for incorporation of new acetylcholine receptors into the plasma membrane of calcium-depleted cells was similar to control cells treated with cycloheximide, suggesting that de novo receptor synthesis was inhibited. These results indicate that intracellular calcium levels and acetylcholine receptor synthesis are not related in a simple reciprocal fashion and suggest that the regulation of acetylcholine receptor levels involves more than one intracellular compartment of calcium.
In vitro resetting of the circadian clock in the Aplysia eye. III. Location of photoreceptors that signal continuous light to continuous darkness
Authors: Prichard RG , Lickey ME
Published: March 2018

As shown in the previous two papers (Prichard, R.G., and M.E. Lickey (1981 a, b) J. Neurosci. 1: 835–839; 840–845), the circadian rhythm of compound action potentials (CAPs) from the Aplysia eye can be reset in vitro by single transitions from continuous light to continuous darkness (LL/DD). The magnitude of the reset depends on the duration of LL that precedes the LL/DD. When LL duration is 18, 21, or 24 hr, the magnitude of the reset is different if the eye is neurally attached to the brain than if it is neurally detached. The brain gives rise to optic efferent fibers that terminate in the retina. In the present paper, we explore how the optic efferents contribute to resetting by asking whether LL/DD is sensed by the photoreceptors known to exist in the brain or those in the eye. Eye-brain preparations were placed in a special recording chamber in which the eye and brain could be isolated photically from each other while one optic nerve remained intact. The LL/DD then was delivered to the eyes and to the brain at different times. During the separate illumination, neural communication between the eyes and brain was prevented by reversible nerve blockade. The magnitude of the resulting resets always corresponded to the duration of LL that was delivered to the eyes. Photoreceptors in the brain did not contribute effectively to resetting. Also, resetting was not disturbed by nerve blockade that began before LL/DD and lasted for more than 6 hr after LL/DD. This implies that information about the timing of LL/DD was stored in the eye for more than 6 hr before it was expressed in the form of a reset. We conclude that the efferent fibers in the optic nerve do not instruct the eye about the magnitude of the reset. Instead, they activate or modulate circadian functions that are latent in the eye itself.
Activity of norepinephrine-containing locus coeruleus neurons in behaving rats anticipates fluctuations in the sleep-waking cycle
Authors: Aston-Jones G , Bloom FE
Published: March 2018

Spontaneous discharge of norepinephrine-containing locus coeruleus (NE- LC) neurons was examined during the sleep-walking cycle (S-WC) in behaving rats. Single unit and multiple unit extracellular recordings yielded a consistent set of characteristic discharge properties. (1) Tonic discharge co-varied with stages of the S-WC, being highest during waking, lower during slow wave sleep, and virtually absent during paradoxical sleep. (2) Discharge anticipated S-WC stages as well as phasic cortical activity, such as spindles, during slow wave sleep. (3) Discharge decreased within active waking during grooming and sweet water consumption. (4) Bursts of impulses accompanied spontaneous or sensory-evoked interruptions of sleep, grooming, consumption, or other such ongoing behavior. (5) These characteristic discharge properties were topographically homogeneous for recordings throughout the NE-LC. (6) Phasic robust activity was synchronized markedly among neurons in multiple unit populations. (7) Field potentials occurred spontaneously in the NE-LC and were synchronized with bursts of unit activity from the same electrodes. (8) Field potentials became dissociated from unit activity during paradoxical sleep, exhibiting their highest rates in the virtual absence of impulses. These results are generally consistent with previous proposals that the NE-LC system is involved in regulating cortical and behavioral arousal. On the basis of the present data and those described in the following report (Aston-Jones, G., and F. E. Bloom (1981) J. Neurosci.1: 887–900), we conclude that these neurons may mediate a specific function within the general arousal framework. In brief, the NE-LC system may globally bias the responsiveness of target neurons and thereby influence overall behavioral orientation.
Appearance and localization of acetylcholinesterase in embryos of the leech Helobdella triserialis
Authors: Fitzpatrick-McElligott S , Stent GS
Published: March 2018

The appearance and localization of acetylcholinesterase (AchE) were studied during embryonic development of the leech Helobdella triserialis. Use of a histochemical stain showed that AchE is present in the polar plasms of the uncleaved leech egg. in the course of the first two cleavages, the AchE is transmitted along with the polar plasms mainly to the D blastomere, precursor of mesoderm and ectoderm. At these early developmental stages, AchE also lines the cleavage furrows between the blastomeres. At later stages, AchE is present in the parental meso- and ectoteloblasts and their daughter stem cells that form the germinal bands. At the completion of germinal band coalescence, AchE is present in the rostral and caudal regions of the germinal plate. Thus, the presence of AchE in the early phase of embryogenesis precedes the formation of any nervous tissue. In the late phase of embryogenesis, once the embryo has reached the stage of body closure and a nervous system is present, the distribution of AchE is that characteristic of the adult leech: AchE is localized in the neuropil of the segmental ganglia of the ventral nerve cord and in the musculature of the body wall. Therefore, at this still quite immature stage, the embryonic nervous system has taken on not only the morphological but also some of the neurochemical characteristics of the adult leech.
Inhibition of sympathetic preganglionic neurons by catecholamines and clonidine: mediation by an alpha-adrenergic receptor
Authors: Guyenet PG , Cabot JB
Published: March 2018

The neuropil surrounding sympathetic preganglionic neurons (SPNs) receives an abundant catecholaminergic innervation originating from the brain stem. The effect of catecholamines (CA) released at this spinal level on the activity of SPNs is still controversial as is the extent to which this particular CA transmission is affected by central antihypertensive drugs, such as clonidine and alpha-methyldopa. The present study was initiated, therefore, to determine the effects of iontophoretic applications of CAs and clonidine on the discharges of identified SPNs and to determine the type of receptor mediating the action of these compounds. Extracellular recordings were made with five- or six-barrel electrodes in 20 pigeons anesthetized with urethane, artificially ventilated, and immobilized. Data were obtained on 83 SPNs localized in the three first thoracic segments and identified on the basis of constancy of antidromic activation latency and collision. All of the cells sampled were inhibited by the application of low iontophoretic currents of clonidine and by a series of CAs, including alpha-methylnorepinephrine, epinephrine, and phenylephrine. For each compound, the amount of charge necessary to decrease the level of cell firing to 50% of control was calculated. Using this value as an index of drug potency, the following rank order could be determined: clonidine greater than alpha-methylnorepinephrine greater than epinephrine greater than norepinephrine greater than phenylephrine. The inhibitory effects of both clonidine and norepinephrine were antagonized by iontophoretic applications of the alpha antagonists, yohimbine, piperoxan, and phentolamine. In contrast, the beta antagonist, sotalol, and the alpha 1 antagonist, prazosin, were found ineffective when similarly applied. It is concluded that CAs and clonidine are inhibitory to the maintained activity of SPNs and that an alpha2-adrenergic receptor may be involved in the action of these compounds.