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1.
iScience ; 24(3): 102190, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33718840

RESUMO

The "Wet Tropics" of Australia host a unique variety of plant lineages that trace their origins to the super-continent of Gondwanaland. While these "ancient" evolutionary records are rightly emphasized in current management of the region, multidisciplinary research and lobbying by Rainforest Aboriginal Peoples have also demonstrated the significance of the cultural heritage of the "Wet Tropics." Here, we evaluate the existing archeological, paleoenvironmental, and historical evidence to demonstrate the diverse ways in which these forests are globally significant, not only for their ecological heritage but also for their preservation of traces of millennia of anthropogenic activities, including active burning and food tree manipulation. We argue that detailed paleoecological, ethnobotanical, and archeological studies, working within the framework of growing national and world heritage initiatives and active application of traditional knowledge, offer the best opportunities for sustainable management of these unique environments in the face of increasingly catastrophic climate change and bushfires.

2.
Nat Ecol Evol ; 5(3): 295-303, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33495592

RESUMO

Little is known about the Pleistocene climatic context of northern Australia at the time of early human settlement. Here we generate a palaeoprecipitation proxy using stable carbon isotope analysis of modern and archaeological pandanus nutshell from Madjedbebe, Australia's oldest known archaeological site. We document fluctuations in precipitation over the last 65,000 years and identify periods of lower precipitation during the penultimate and last glacial stages, Marine Isotope Stages 4 and 2. However, the lowest effective annual precipitation is recorded at the present time. Periods of lower precipitation, including the earliest phase of occupation, correspond with peaks in exotic stone raw materials and artefact discard at the site. This pattern is interpreted as suggesting increased group mobility and intensified use of the region during drier periods.


Assuntos
Fósseis , Pandanaceae , Arqueologia , Austrália , Humanos , Ocupações
3.
Nat Commun ; 11(1): 924, 2020 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066741

RESUMO

There is little evidence for the role of plant foods in the dispersal of early modern humans into new habitats globally. Researchers have hypothesised that early movements of human populations through Island Southeast Asia and into Sahul were driven by the lure of high-calorie, low-handling-cost foods, and that the use of plant foods requiring processing was not common in Sahul until the Holocene. Here we present the analysis of charred plant food remains from Madjedbebe rockshelter in northern Australia, dated to between 65 kya and 53 kya. We demonstrate that Australia's earliest known human population exploited a range of plant foods, including those requiring processing. Our finds predate existing evidence for such subsistence practices in Sahul by at least 23ky. These results suggest that dietary breadth underpinned the success of early modern human populations in this region, with the expenditure of labour on the processing of plants guaranteeing reliable access to nutrients in new environments.


Assuntos
Domesticação , Comportamento Alimentar , Migração Humana/história , Plantas Comestíveis , Austrália , Manipulação de Alimentos/história , Fósseis , História Antiga , Humanos
4.
Ann Bot ; 125(4): 581-597, 2020 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-31903489

RESUMO

BACKGROUND: Vegetatively propagated crops are globally significant in terms of current agricultural production, as well as for understanding the long-term history of early agriculture and plant domestication. Today, significant field crops include sugarcane (Saccharum officinarum), potato (Solanum tuberosum), manioc (Manihot esculenta), bananas and plantains (Musa cvs), sweet potato (Ipomoea batatas), yams (Dioscorea spp.) and taro (Colocasia esculenta). In comparison with sexually reproduced crops, especially cereals and legumes, the domestication syndrome in vegetatively propagated field crops is poorly defined. AIMS AND SCOPE: Here, a range of phenotypic traits potentially comprising a syndrome associated with early domestication of vegetatively propagated field crops is proposed, including: mode of reproduction, yield of edible portion, ease of harvesting, defensive adaptations, timing of production and plant architecture. The archaeobotanical visibility of these syndrome traits is considered with a view to the reconstruction of the geographical and historical pathways of domestication for vegetatively propagated field crops in the past. CONCLUSIONS: Although convergent phenotypic traits are identified, none of them are ubiquitous and some are divergent. In contrast to cereals and legumes, several traits seem to represent varying degrees of plastic response to growth environment and practices of cultivation, as opposed to solely morphogenetic 'fixation'.


Assuntos
Domesticação , Manihot , Agricultura , Produtos Agrícolas , Grão Comestível
5.
J Zoo Wildl Med ; 50(1): 270-273, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31120690

RESUMO

The prevalence and intensity of infection with digestive, liver, and pulmonary parasites in wild boars in Romania was determined by examination of 280 cadavers from 26 hunting grounds during the period 2012-2016. Eleven genera of parasites were recovered: nine within the digestive system (Eimeria, Ascaris, Globocephalus, Gongylonema, Hyostrongylus, Oesophagostomum, Physocephalus, Trichuris, and Macracanthorinchus); and two (Dicrocoelium, Metastrongylus ) located in the hepatic and pulmonary systems. The overall prevalence of infection was 80.7% (n = 280). Polyparasitism was found in 82.8% of positive cases. The mean intensity of parasitism was highest for pulmonary parasites (Metastrongylus salmi, 25.95). Regarding gastrointestinal parasites, the highest mean intensity occurred in the case of Oesophagastomum dentatum infections (22.14), whilst the lowest was that of Macracanthorhynchus hirudinaceus (1.66). Wild boars are an important source of infection for domestic pigs in Romania and neighboring countries where extensive breeding systems occur.


Assuntos
Enteropatias Parasitárias/veterinária , Pneumopatias Parasitárias/veterinária , Doenças dos Suínos/epidemiologia , Animais , Animais Selvagens , Fezes/parasitologia , Feminino , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Pneumopatias Parasitárias/epidemiologia , Pneumopatias Parasitárias/parasitologia , Masculino , Prevalência , Romênia/epidemiologia , Sus scrofa , Suínos , Doenças dos Suínos/parasitologia
6.
Nature ; 547(7663): 306-310, 2017 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-28726833

RESUMO

The time of arrival of people in Australia is an unresolved question. It is relevant to debates about when modern humans first dispersed out of Africa and when their descendants incorporated genetic material from Neanderthals, Denisovans and possibly other hominins. Humans have also been implicated in the extinction of Australia's megafauna. Here we report the results of new excavations conducted at Madjedbebe, a rock shelter in northern Australia. Artefacts in primary depositional context are concentrated in three dense bands, with the stratigraphic integrity of the deposit demonstrated by artefact refits and by optical dating and other analyses of the sediments. Human occupation began around 65,000 years ago, with a distinctive stone tool assemblage including grinding stones, ground ochres, reflective additives and ground-edge hatchet heads. This evidence sets a new minimum age for the arrival of humans in Australia, the dispersal of modern humans out of Africa, and the subsequent interactions of modern humans with Neanderthals and Denisovans.


Assuntos
Migração Humana/história , África/etnologia , Animais , Austrália , Dieta/história , Fósseis , Sedimentos Geológicos/análise , História Antiga , Humanos , Homem de Neandertal
7.
J Hum Evol ; 83: 46-64, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25957653

RESUMO

Published ages of >50 ka for occupation at Madjedbebe (Malakunanja II) in Australia's north have kept the site prominent in discussions about the colonisation of Sahul. The site also contains one of the largest stone artefact assemblages in Sahul for this early period. However, the stone artefacts and other important archaeological components of the site have never been described in detail, leading to persistent doubts about its stratigraphic integrity. We report on our analysis of the stone artefacts and faunal and other materials recovered during the 1989 excavations, as well as the stratigraphy and depositional history recorded by the original excavators. We demonstrate that the technology and raw materials of the early assemblage are distinctive from those in the overlying layers. Silcrete and quartzite artefacts are common in the early assemblage, which also includes edge-ground axe fragments and ground haematite. The lower flaked stone assemblage is distinctive, comprising a mix of long convergent flakes, some radial flakes with faceted platforms, and many small thin silcrete flakes that we interpret as thinning flakes. Residue and use-wear analysis indicate occasional grinding of haematite and woodworking, as well as frequent abrading of platform edges on thinning flakes. We conclude that previous claims of extensive displacement of artefacts and post-depositional disturbance may have been overstated. The stone artefacts and stratigraphic details support previous claims for human occupation 50-60 ka and show that human occupation during this time differed from later periods. We discuss the implications of these new data for understanding the first human colonisation of Sahul.


Assuntos
Arqueologia/métodos , Ocupações/história , Artefatos , Austrália , História Antiga , Humanos , Tecnologia/história
8.
Talanta ; 116: 149-54, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24148386

RESUMO

The objective of this study was to discriminate by a NIR line scan hyperspectral imaging, taxonomic plant families comprised of different grassland species. Plants were collected from semi-natural meadows of the National Apuseni Park, Apuseni Mountains, Gârda area (Romania) according to botanical families. Chemometric tools such as PLS-DA were used to discriminate distinct grassland species, and assign the different species to botanical families. Species within the Poacea family and other Botanical families could be distinguished (R(2)=0.91 and 0.90, respectively) with greater accuracy than those species in the Fabacea family (R(2)=0.60). A correct classification rate of 99% was obtained in the assignment of the various species to the proper family. Moreover a complete study based on wavelength selection has been performed in order to identify the chemical compound related to each botanical family and therefore to the possible toxicity of the plant. This work could be considered as a first step for the development of a complete procedure for the detection and quantification of possible toxic species in semi-natural meadows used by grazing animals.


Assuntos
Fabaceae/química , Plantas Tóxicas/química , Poaceae/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Algoritmos , Biota , Calibragem , Análise Discriminante , Fabaceae/classificação , Plantas Tóxicas/classificação , Poaceae/classificação , Romênia
9.
Brain Res ; 880(1-2): 11-6, 2000 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-11032985

RESUMO

The binding sites of nociceptin (also named orphanin FQ), the endogenous ligand of ORL1 (opiate receptor like 1), were localized in rat brain, using an autoradiographic procedure. High levels of binding were observed in the cingulate, retrosplenial, perirhinal, insular and occipital cortex, anterior and posteromedial cortical amygdaloid nuclei, basolateral amygdaloid nucleus, amygdaloid complex, posterior hippocampus, dorsal endopiriform, central medial thalamic, paraventricular, rhomboid thalamic, suprachiasmatic, ventromedial hypothalamic nuclei, mammillary complex, superficial gray layer of the superior colliculus, locus coeruleus, dorsal raphe nucleus. More moderate labelling was observed in the prefrontal, fronto-parietal, temporal, piriform cortex, dentate gyrus, anterior olfactory nucleus, olfactory tubercle, shell of nucleus accumbens, claustrum, lateral septum, laterodorsal thalamic, medial habenular, subthalamic, reuniens thalamic nuclei, subiculum, periaqueductal grey matter and pons. A lower binding site density was observed in the anterior and medial hippocampus, olfactory bulb, caudate putamen, the core of the nucleus accumbens, medial septum, ventrolateral, ventroposterolateral and mediodorsal thalamic nuclei, lateral and medial geniculate nuclei, hypothalamic area, substantia nigra, ventral tegmentum area and interpedoncular nucleus. A moderate and similar labelling was found in the dorsal and ventral horn of the spinal cord. No labelling was apparent in the corpus callosum. Thus, it appears that the ORL1 receptor is particularly abundant in the cerebral cortex, limbic system of the rat brain and some areas involved in pain perception.


Assuntos
Encéfalo/metabolismo , Peptídeos Opioides/farmacocinética , Receptores Opioides/metabolismo , Medula Espinal/metabolismo , Animais , Autorradiografia/métodos , Encéfalo/citologia , Masculino , Especificidade de Órgãos , Ratos , Ratos Sprague-Dawley , Receptores Opioides/agonistas , Receptores Opioides/análise , Medula Espinal/citologia , Trítio , Receptor de Nociceptina
10.
J Synchrotron Radiat ; 7(Pt 5): 301-6, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16609212

RESUMO

Synchrotron beam measurements were performed with a single-photon-counting pixel detector to investigate the influence of threshold settings on charge sharing. Improvement of image homogeneity by adjusting the threshold of each pixel individually was demonstrated. With a flat-field correction, the homogeneity could be improved. A measurement of the point spread function is reported.

11.
Life Sci ; 65(25): 2727-33, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10622282

RESUMO

Prepronociceptin contains, in addition to nociceptin, other potentially excisable peptides which may have physiological significance. We have here considered NocII, a heptadecapeptide whose sequence lies immediately downstream of that of nociceptin in the precursor polypeptide, as well as NocIII which corresponds to NocII extended by a stretch of three arginine residues. When i.c.v.-administered in mice, NocII (10-10,000 ng) stimulated horizontal locomotor activity and decreased the latency to paw licking but neither to rearing nor escape jumping in the hot plate test (55 degrees C). When nociceptin (100 ng) and NocII (100 ng) were simultaneously intracerebroventricularly injected, each peptide produced its own effect without modifying the effect of the other. NocII was ineffective in the tail flick and writhing tests. NocIII (NocII-Arg-Arg-Arg) was inactive in all tests, even when assayed as long as 40 min following i.c.v. administration. The fact that NocII, but not its very close structural analogue NocII, is biologically active indicates that their may exist a specific receptor to NocII.


Assuntos
Comportamento Animal/efeitos dos fármacos , Neuropeptídeos/farmacologia , Sequência de Aminoácidos , Animais , Temperatura Corporal , Comportamento Exploratório/efeitos dos fármacos , Injeções Intraventriculares , Masculino , Camundongos , Dados de Sequência Molecular , Atividade Motora/efeitos dos fármacos , Neuropeptídeos/química , Nociceptores/efeitos dos fármacos , Nociceptores/fisiologia , Peptídeos Opioides/administração & dosagem , Peptídeos Opioides/química , Peptídeos Opioides/farmacologia , Medição da Dor , Vasodilatadores/administração & dosagem , Vasodilatadores/química , Vasodilatadores/farmacologia
12.
Fundam Clin Pharmacol ; 12(4): 420-5, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9711464

RESUMO

The effects on nociperception of nociceptin/Orphanin FQ (noc/OFQ), the endogenous ligand of the ORL1 (opioid receptor like 1) receptor, have been evaluated in mice upon intracerebroventricular injection of 10 to 10,000 ng doses of the peptide. In the hot plate test (55 degrees C) the licking, rearing and jump latencies were significantly reduced by noc/OFQ (100-250 ng). Noc/OFQ (100-1000 ng) also reduced the latency to tail withdrawal in the tail flick test. In the formalin test (injection in a hind paw of a formalin solution), noc/OFQ (100 ng) increased significantly the duration of paw licking and/or biting at the earliest period of observation. In the writhing test, the number of writhes evoked by intraperitoneal administration of dilute acetic acid was not modified by noc/OFQ at doses in the range of 10-1000 ng, but was decreased by 10,000 ng. The reduction in jump latency in the hot plate test was observed even when mice were pretreated with morphine (2 mg/kg, s.c.). The analgesic effect of acetorphan (5 mg/kg, i.v.) was also reduced by nociceptin (100 ng); on the other hand the hyperalgesic effect of naloxone (4.5 mg/kg, s.c.) was not additive with that of nociceptin (100 ng). Comparing in various tests the nociceptive thresholds of uninjected mice to that of saline i.c.v. injected mice, it appeared that the latter injection induced an increase in these thresholds which was prevented by nociceptin. It is suggested that nociceptin displays hyperalgesic effects by preventing autoanalgesic (opioidergic) mechanisms triggered by the stress elicited by intracerebroventricular injection.


Assuntos
Hiperalgesia/induzido quimicamente , Peptídeos Opioides/farmacologia , Analgesia , Analgésicos Opioides , Análise de Variância , Animais , Hiperalgesia/fisiopatologia , Injeções Intraventriculares , Masculino , Camundongos , Dor/tratamento farmacológico , Dor/fisiopatologia , Medição da Dor , Estresse Fisiológico/fisiopatologia
13.
C R Seances Soc Biol Fil ; 192(6): 1099-109, 1998.
Artigo em Francês | MEDLINE | ID: mdl-10101606

RESUMO

Among the opioid receptors family, the cloning of the mu, kappa and delta receptors was followed by that of another member, named ORL1 (Opiate Receptor Like 1). In spite of obvious homologies with the mu, kappa and delta receptors, ORL1 does not display a relevant affinity for the endogenous ligands of these former receptors (beta endorphin, enkephalins, dynorphin A...). This observation has prompted to search for an endogenous ligand of ORL1. A heptadecapeptide which fulfils this function, with a nanomolar affinity, has been found. It was named either nociceptin or orphanin FQ. It demonstrates, according either to the dose or to the route of administration, hyperalgesic, allodynic, antiopioidergic or even analgesic effects. It displays also many behavioural effects, modifying especially locomotion, exploratory behaviour, motivation, anxiety, memory, food intake. Nociceptin results from the cleavage of a large precursor protein, prepronociceptin (PPNOC). In this latter, nociceptin is flanked on its C-terminal region by another peptide which may be regarded either as a heptadecapeptide (NocII), or a bidecapeptide (NocIII) according to the inclusion or not of a fragment constituted by 3 arginine residues. Investigating the functions modulated by NocII, we observed that it stimulates locomotor activity of mice and shortens the forepaws licking latency in the hot plate test (55 degrees C); these effects are not shared by NocIII. The simultaneous administration of NocII and nociceptin resulted in animals put on the hot plate to the appearance of their respective effects, not modified by the presence of the other. A 41 amino acid peptide flanks nociceptin on its N-terminal region in PPNOC. It may be cleaved to generate a heptadecapeptide, named nocistatin on account of its antagonist effect on the hyperalgesia/allodynia induced by nociceptin. Thus, the discovery of ORL1 has led to that of nociceptin, that of its precursor PPNOC, and thereby to that of NocII/NocIII and nocistatin. The functions modulated by these peptides are being investigated whereas their receptors are yet unknown. These multiple targets allow to expect new strategies to modulate their functions.


Assuntos
Peptídeos Opioides/genética , Peptídeos Opioides/farmacologia , Receptores Opioides/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Clonagem Molecular , Humanos , Camundongos , Atividade Motora/efeitos dos fármacos , Peptídeos Opioides/fisiologia , Precursores de Proteínas/biossíntese , Precursores de Proteínas/genética , Receptor de Nociceptina
14.
Neurosci Lett ; 230(1): 33-6, 1997 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-9259457

RESUMO

The binding sites of [3H]nociceptin (also named Orphanin FQ), the endogenous ligand of the ORL1 (opiate receptor like 1) receptor, were localized in the central nervous system of the mouse using an autoradiographic procedure. A high density of binding sites was seen in the cerebral cortex, paraventricular nucleus of the thalamus, amygdaloid complex, suprachiasmatic nucleus, medial thalamus and medial geniculate nucleus. Moderate binding was observed in the nucleus accumbens, lateral septum, lateral thalamus, hippocampus, periaqueductal grey matter and pons. Finally, low levels of binding were seen in the striatum, olfactory tubercle, hypothalamus and substantia nigra. Thus, it appears that the ORL1 receptor is particularly abundant in the cerebral cortex and limbic system of the mouse brain.


Assuntos
Encéfalo/metabolismo , Peptídeos Opioides/metabolismo , Receptores Opioides/agonistas , Tonsila do Cerebelo/metabolismo , Animais , Autorradiografia/métodos , Sítios de Ligação , Córtex Cerebral/metabolismo , Masculino , Mesencéfalo/metabolismo , Camundongos , Especificidade de Órgãos , Núcleo Supraquiasmático/metabolismo , Telencéfalo/metabolismo , Núcleos Talâmicos/metabolismo , Tálamo/metabolismo , Trítio
15.
Neuroreport ; 8(3): 705-7, 1997 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-9106751

RESUMO

NocII is a heptadecapeptide whose sequence lies immediately downstream of nociceptin, the newly discovered natural agonist of the ORL1 receptor, in pronociceptin, nociceptin's precursor polypeptide. Since the sequence of NocII is framed by putative convertase excision sites and it totally conserved across murine and human species, we have sought to determine whether this orphan neuropeptide might by physiologically significant, i.e. endowed with central biological activity in vivo. Intracerebroventricular administration of 10 and 100 ng of NocII increased locomotion in mice. However, unlike nociceptin, which stimulates both the horizontal and vertical (rearing) components of locomotion, NocII affected only the horizontal component. The motor stimulant action of NocII appears to depend largely on dopamine transmission since it is totally reversed by the D1 or the D2 dopamine receptor antagonists SCH 23390 and haloperidol. NocII does not modify the number of explored holes in the hole board test, indicating that, unlike nociceptin, the orphan peptide does not affect exploratory behavior in mice.


Assuntos
Comportamento Exploratório/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Neuropeptídeos/farmacologia , Peptídeos Opioides/farmacologia , Sequência de Aminoácidos , Animais , Benzazepinas/farmacologia , Sequência Conservada , Antagonistas de Dopamina/farmacologia , Relação Dose-Resposta a Droga , Haloperidol/farmacologia , Humanos , Masculino , Camundongos , Dados de Sequência Molecular , Neuropeptídeos/química , Receptores de Dopamina D1/fisiologia , Receptores de Dopamina D2/fisiologia , Receptores Opioides/agonistas
16.
Eur J Pharmacol ; 317(1): 9-13, 1996 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-8982713

RESUMO

The recently characterized heptadecapeptide nociceptin, the endogenous agonist of the orphan opioid receptor-like 1 (ORL1 receptor), has been tested for its effects on locomotion and exploratory behaviour in mice. I.c.v. administration of as little as 10 ng of nociceptin/animal stimulated locomotor activity. This effect was dose-dependent, increasing in intensity up to 100 ng and in duration for doses in the range of 1000-10000 ng. The stimulation of horizontal locomotion elicited by 100 ng nociceptin was accompanied by a stimulation of the vertical component of locomotion. These effects were not reversed by high doses (1.5 and 4.5 mg/kg s.c.) of the opioid receptor antagonist naloxone. Increasing doses of the dopamine D2 receptor antagonist haloperidol (0.1-0.5 mg/kg i.p.) as well as of the dopamine D1 receptor antagonist SCH 23390 [R(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1 H-3-benzazepine hydrochloride] (0.0075-0.03 mg/kg s.c.) reversed this effect, suggesting that nociceptin exerts its motor-stimulant actions by increasing central dopaminergic transmission. Nociceptin was also found to increase the number of head dips in the hole-board test, indicating that the peptide stimulates exploratory behaviour.


Assuntos
Comportamento Exploratório/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Peptídeos Opioides/farmacologia , Receptores Opioides/agonistas , Animais , Benzazepinas/farmacologia , Antagonistas de Dopamina/farmacologia , Relação Dose-Resposta a Droga , Haloperidol/farmacologia , Injeções Intraventriculares , Masculino , Camundongos , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Peptídeos Opioides/administração & dosagem , Peptídeos Opioides/antagonistas & inibidores , Estimulação Química , Receptor de Nociceptina
17.
Br J Clin Pharmacol ; 40(6): 545-52, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8703660

RESUMO

1. The dose-related effects of azapropazone on (i) event-related and spontaneous EEG-activity and (ii) the subjects' pain ratings were investigated using an experimental human pain model based on both chemo-somatosensory event-related potentials (CSSERP) and subjects' pain ratings. 2. Healthy subjects (n = 20) participated in a placebo-controlled, randomized, double-blind, four-way cross-over study. Single doses of azapropazone (300 mg, 600 mg and 1200 mg) and placebo were administered intravenously. Each experiment consisted of five sessions (before and 1, 2, 4 and 8 h after administration of the medication). Each session lasted for approximately 40 min. In the first 20 min, pain was induced by short CO2-stimuli presented to the right nostril (phasic pain; interstimulus interval 30 s) and EEG was recorded from five positions. CSSERPs were obtained in response to painful CO2-stimuli. In the following 20 min period, tonic pain was induced by a constant stream of dry air introduced in the left nostril. Subjects rated the intensity of both phasic and tonic pain by means of a visual analogue scale. Additionally, a frequency analysis of the spontaneous EEG was performed. 3. Azapropazone reduced the pain-related CSSERP-amplitudes at frontal and parietal recording positions. This topographical pattern was observed in previous studies with opioids, while NSAIDs such as flurbiprofen and ketoprofen exerted effects at frontal and central positions. In contrast to other NSAIDs, administration of azapropazone resulted in a reduction of the frequency bands alpha 1, delta and theta of the spontaneous EEG. At the subjective level, analgesic effects of azapropazone were observed in the ratings of tonic pain. 4. Analgesic properties of azapropazone were demonstrated in man. The topographical pattern of the changes in the CSSERPs and the effects on EEG background activity suggest a central component of the analgesic action of azapropazone.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Apazona/farmacologia , Eletroencefalografia/efeitos dos fármacos , Dor/fisiopatologia , Adulto , Anti-Inflamatórios não Esteroides/administração & dosagem , Apazona/administração & dosagem , Estudos Cross-Over , Método Duplo-Cego , Potenciais Somatossensoriais Evocados , Feminino , Humanos , Masculino , Medição da Dor/efeitos dos fármacos
18.
J Pharmacol Exp Ther ; 274(1): 231-41, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7616403

RESUMO

Following reserpine pretreatment to disrupt vesicular stores of dopamine and norepinephrine, in vivo microdialysis was used in behaving rats to evaluate the role of vesicles in the neurochemical and behavioral responses to amphetamine and cocaine. Reserpine (2.5 mg/kg, 24 hr) completely prevented the hippocampus norepinephrine responses to 20 mg/kg of cocaine and to 0.5, 1.25 and 5.0 mg/kg of amphetamine. Likewise, reserpine almost completely abolished the caudate putamen dopamine response to cocaine. In contrast, the effect of reserpine on the amphetamine-induced dopamine response varied as a function of amphetamine dose. Although the dopamine response to 1.25 mg/kg of amphetamine was unchanged by reserpine pretreatment, the dopamine responses to both the lowest (0.5 mg/kg) and highest (5.0 mg/kg) doses of amphetamine were significantly attenuated by about 65% and 50%, respectively. These results indicate that the norepinephrine response to amphetamine is dependent on vesicular stores of transmitter at all doses of the drug. However, although amphetamine can release dopamine from a reserpine-resistant (non-vesicular) pool, it also appears that this response partially depends on vesicular stores, especially at low and high doses of drug. Concomitant behavioral assessments revealed that the behavioral responses to cocaine and the lowest dose of amphetamine, like the dopamine responses, were significantly suppressed by reserpine pretreatment. In contrast, at the intermediate dose of amphetamine, stereotypies were significantly enhanced. These altered behavioral profiles are discussed in terms of a balance between increases in both dopamine and norepinephrine produced by amphetamine.


Assuntos
Anfetamina/farmacologia , Comportamento Animal/efeitos dos fármacos , Cocaína/farmacologia , Dopamina/metabolismo , Norepinefrina/metabolismo , Reserpina/farmacologia , Animais , Núcleo Caudado/efeitos dos fármacos , Núcleo Caudado/metabolismo , Clorgilina/farmacologia , Interações Medicamentosas , Espaço Extracelular/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
19.
Behav Neurosci ; 109(3): 532-46, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7662163

RESUMO

In order to examine the hypothesis that N-methyl-D-aspartate (NMDA) receptors are selectively involved in the development of stimulant sensitization, we characterized the interaction between acute and chronic dizocilpine (MK-801) + amphetamine using a detailed behavioral analysis, including concurrent assessment of the locomotor and stereotype components of the stimulant response and continuous monitoring of all the various phases of the emergent sensitization. The results showed that MK-801 (0.125 mg/kg) significantly affected the acute response to amphetamine (0.5, 1.75, 4.0 mg/kg), increasing or decreasing locomotor activity depending on dose. Repeated administration of MK-801 + amphetamine resulted in a suppression of stereotyped behaviors and a potentiated locomotor sensitization. These findings suggest that rather than blocking the development of sensitization, MK-801 pretreatment may produce a unique behavioral augmentation that is apparent during coadministration and that persists up to 48 hr in the response to amphetamine challenge.


Assuntos
Anfetamina/antagonistas & inibidores , Nível de Alerta/efeitos dos fármacos , Maleato de Dizocilpina/farmacologia , Atividade Motora/efeitos dos fármacos , Anfetamina/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Comportamento Estereotipado/efeitos dos fármacos
20.
Brain Res ; 654(1): 53-62, 1994 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-7982098

RESUMO

Microdialysis in behaving animals was used to characterize the hippocampus (HP) and prefrontal cortex (PFC) norepinephrine (NE) responses to amphetamine (AMPH) and cocaine (COC). NE exhibited regionally similar dose- and time-dependent increases to each drug. However, peak NE concentrations were approximately 2-fold greater at behaviorally similar doses of AMPH compared with COC. To examine the role of noradrenergic impulse flow in the mechanism(s) by which these stimulants enhance extracellular NE, groups of animals were pretreated with the alpha 2 autoreceptor agonist, clonidine (CLON), prior to stimulant administration. CLON (50 micrograms/kg) administration completely blocked the NE response to both 20 and 30 mg/kg COC. By contrast, CLON decreased the NE response to 0.5 mg/kg AMPH by 75%, but became progressively less effective on the response as the dose was increased to 1.75 and 5.0 mg/kg. CLON also had no effect on the caudate dopamine responses to either AMPH or COC, consistent with the presumed specificity of this drug for alpha 2 receptors and suggesting the absence of any significant pharmacokinetic interactions. These results indicate that COC acts an uptake blocker at NE-containing neurons and suggest that AMPH increases extracellular NE through two consequences of its interaction with the neuronal transport carrier: (1) reuptake blockade which predominates at lower doses; and (2) release which becomes more prevalent at higher doses. Behavioral analyses revealed effects of CLON which varied as a function of stimulant and dose.


Assuntos
Anfetamina/farmacologia , Química Encefálica/efeitos dos fármacos , Clonidina/farmacologia , Cocaína/farmacologia , Norepinefrina/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Dopamina/metabolismo , Relação Dose-Resposta a Droga , Espaço Extracelular/efeitos dos fármacos , Espaço Extracelular/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Microdiálise , Atividade Motora/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Ratos , Ratos Sprague-Dawley
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