As we age, our ability to cope with a variety of stresses significantly decreases. One of the features of an ageing organism is the dramatic increase in the number of cells arrested in the G1 phase, a process known as senescence. It is well established that the senescence phenotype leads to a change in the way cells respond to stress. However, the molecular mechanisms by which these cells cope and/or respond to a variety of environmental challenges remain unknown. In general, cells respond to stress by engaging a variety of mechanisms; one of them is the assembly of cytoplasmic foci known as stress granules (SGs). These entities are considered as part of the survival pathways that are activated at the beginning of any stress to protect key cellular elements which allow a quick recovery if the stress is rapidly removed. However, we do not know whether SGs formation is activated during senescence. In this study, we investigated the formation and the role of SGs in senescent cells exposed to various stresses. We demonstrated that while SGs can assemble in response to oxidative stress (OS) during all the steps leading to senescence activation, their number significantly increases at late stage of senescence. This increase correlates with a rapid decrease in the expression of the cyclin kinase inhibitor p21, one of the main players in the activation of the senescence phenotype. Although the OS-induced recruitment of p21 mRNA to SGs correlates with a significant increase in its half-life, this translocation interferes with p21 translation only at late senescence. This translation inhibition could be explained by the co-recruitment of CUGBP1, a known translation activator during senescence of p21, and p21 mRNA to SGs. Therefore, our data suggest that SGs formation and the reduction in p21 protein levels represent two main events through which senescent cells respond to stress conditions.

Previous findings showed that mild chronic restraint stress causes motor impairments in rats. These behavioural impairments might be related to molecular changes in brain areas that regulate motor functions, such as the cerebellum. Little is known about the role of the cerebellum in stress-induced behavioural alteration. We hypothesized that alteration in animal behaviour after chronic restraint stress is due to brain-specific changes in miRNA and proteins encoding gene expression. Our results revealed that expression of three miRNAs and 39 mRNAs was changed significantly after two weeks of stress. Furthermore, we verified one putative target for one of the changed miRNAs and expression of four randomly selected genes. Changes in gene expression disappeared after two weeks of recovery from stress. These findings provide a novel insight into stress-related mechanisms of gene expression underlying altered behavioural performance. The observations bear implications for the prevention and treatment of stress-related disorders and disease. / xii, 109 leaves. : ill. ; 29 cm

Thesis (M.Sc.)--Memorial University of Newfoundland, 2003. / Restricted until October 2004. Bibliography: leaves 90-116.

During adolescence, animals leave the natal home and interact with potentially threatening stimuli (i.e. stressors), e.g. unfamiliar environments and conspecifics. Adolescent stressors can result in fewer interactions with unfamiliar stimuli in adulthood, plausibly due to sustained effects of glucocorticoid exposure on stress physiology (e.g. glucocorticoid secretion and receptor expression). The current thesis tested the hypothesis that adolescent glucocorticoid exposure and social experiences act as stressors by quantifying the effects of the adolescent experiences on behavioural responses to unfamiliar stimuli and the underlying neuroendocrine mechanisms when in adulthood using two captive species, zebra finches and rats. In study one, adolescent zebra finches were dosed with the glucocorticoid corticosterone. In adulthood, birds dosed with corticosterone in early adolescence took longer to enter an unfamiliar environment when tested individually and had lower expression of the glucocorticoid receptor GR in the hippocampus and hypothalamus, brain regions that regulate stress responses. Glucocorticoids therefore appear to be an endocrine mechanism behind the long-term effects of adolescent stress. Subsequent studies explored whether higher social density and more unfamiliar social interactions during adolescence act as stressors. In study two, early adolescent zebra finches were housed in groups varying in conspecific number and density. In adulthood, females raised in larger groups secreted a higher stressor-induced corticosterone concentration and, if raised at lower density, spent more time in an unfamiliar environment when group housed. In study three, adolescent female rats were housed in familiar pairs or exposed to unfamiliar conspecifics. Unfamiliar adolescent interactions had no effects on responses to unfamiliar environments or stress physiology in adulthood, but heightened ultrasonic call rates. In this thesis, adolescent social experiences do not act like stressors, but modulate (especially female) social behaviour. Adolescent stressors and social experiences therefore have distinct effects on responses to unfamiliar stimuli and stress physiology that are maintained into adulthood.

Made available in DSpace on 2014-06-11T19:32:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-01-14Bitstream added on 2014-06-13T21:05:30Z : No. of bitstreams: 1 santos_vg_dr_botfmvz.pdf: 418050 bytes, checksum: ff8ea12e28e936c31b32dcbb33f589a4 (MD5) / Avaliou-se a ação imunoestimulante da própolis bruta em dietas para tilápia-do-Nilo submetidas a desafio com a Aeromonas hydrophila. Foram alojados 280 peixes (50 ± 5,7 g) em 35 aquários circulares (250 L), oito peixes/aquário. O delineamento estatístico utilizado foi inteiramente casualizado, caracterizado por sete tratamentos, dieta controle e as demais com suplementação de própolis de 0,5; 1,0; 1,5; 2,0; 2,5 e 3,0% com cinco repetições. Os peixes foram pesados no início e final do experimento para avaliação dos parâmetros de desempenho produtivo. Após trinta dias, 16 peixes de cada tratamento foram anestesiados com benzocaína (1,0g/15L de água) para coleta do sangue e avaliação dos parâmetros hematológicos e imunológicos, caracterizando período anterior ao desafio bacteriano. Os parâmetros hematológicos e imunológicos avaliados foram: número de eritrócitos, porcentagem de hematócrito, taxa de hemoglobina, volume corpuscular médio (VCM), concentração de hemoglobina corpuscular média (CHCM) e peróxido de hidrogênio e óxido nitrico (NO). Em seguida, oito peixes de cada tratamento foram inoculados com injeção intraperitoneal com cultura da bactéria contendo 2,0x107UFC/mL e transferidos para 28 aquários plásticos (40L), dois peixes por aquário. Os mesmos parâmetros foram avaliados após 15 dias. Os resultados demonstraram que níveis elevados de própolis bruta influenciaram na redução do ganho de peso e da hemoglobina e aumento do NO. Comparando-se os momentos, observou-se que após o desafio, os peixes apresentaram valores menores de hematócrito, VCM, neutrófilos e NO e maior CHCM. Concluiu-se que a própolis bruta interferiu no crescimento e na saúde da tilápia-do-Nilo / Immunostimulant effects of crude propolis supplementation on diets to Nile tilapia, submitted to Aeromonas hydrophila, were investigated. Thus, 280 Nile tilapia (initial weight = 50 ± 5,7 g/fish), were allocated in 35 tanks (250 l), eight fish/tank. The experiment was conducted in a completely randomized design, characterized by seven treatments, diet control and the other with propolis supplementation of 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0% with five repetitions. The fish were weighed at the beginning and final of experimental for evaluating the performance parameters. After thirty days, 16 fishes/treatment were anesthetized with benzocaine (1.0g/15L of water), and collected blood to evaluation to haematological and immunological parameters, characterizing the period before to bacterial challenge. The parameters analized were: red blood cell count , haematocrit, haemoglobin, mean corpuscular volume (MCV), mean corpuscular haemoglobin concentration (MCHC), and hydrogen peroxide and nitric oxide (NO). Then, eight fish of each treatment were inoculated with intraperitoneal injection with culture of A. Hydrophila containing 2.0x107UFC/mL, and transferred to twenty eight plastic tanks (40L), and two fishes per tank. The same haematological and immunological parameters were evaluated after fifteen days. The results showed that high levels of crude propolis influence at decrease of weight gain and Hb, an increase of NO. Comparing the moments, was observed that after challenge the fishes showed low value of Htc, MCV, neutrophils and NO, also high value of MCHC. It was concluded that crude propolis affect the growth and health of the-Nile tilapia

Orientador: Margarida Maria Barros / Coorientador: Ricardo de Oliveira Orsi / Banca: Luiz Edivaldo Pezzato / Banca: Lidia Mara Ruv Carelli Barreto / Banca: Maria José Tavares Ranzani de Paiva / Banca: Igo Gomes Guimarães / Resumo: Avaliou-se a ação imunoestimulante da própolis bruta em dietas para tilápia-do-Nilo submetidas a desafio com a Aeromonas hydrophila. Foram alojados 280 peixes (50 ± 5,7 g) em 35 aquários circulares (250 L), oito peixes/aquário. O delineamento estatístico utilizado foi inteiramente casualizado, caracterizado por sete tratamentos, dieta controle e as demais com suplementação de própolis de 0,5; 1,0; 1,5; 2,0; 2,5 e 3,0% com cinco repetições. Os peixes foram pesados no início e final do experimento para avaliação dos parâmetros de desempenho produtivo. Após trinta dias, 16 peixes de cada tratamento foram anestesiados com benzocaína (1,0g/15L de água) para coleta do sangue e avaliação dos parâmetros hematológicos e imunológicos, caracterizando período anterior ao desafio bacteriano. Os parâmetros hematológicos e imunológicos avaliados foram: número de eritrócitos, porcentagem de hematócrito, taxa de hemoglobina, volume corpuscular médio (VCM), concentração de hemoglobina corpuscular média (CHCM) e peróxido de hidrogênio e óxido nitrico (NO). Em seguida, oito peixes de cada tratamento foram inoculados com injeção intraperitoneal com cultura da bactéria contendo 2,0x107UFC/mL e transferidos para 28 aquários plásticos (40L), dois peixes por aquário. Os mesmos parâmetros foram avaliados após 15 dias. Os resultados demonstraram que níveis elevados de própolis bruta influenciaram na redução do ganho de peso e da hemoglobina e aumento do NO. Comparando-se os momentos, observou-se que após o desafio, os peixes apresentaram valores menores de hematócrito, VCM, neutrófilos e NO e maior CHCM. Concluiu-se que a própolis bruta interferiu no crescimento e na saúde da tilápia-do-Nilo / Abstract: Immunostimulant effects of crude propolis supplementation on diets to Nile tilapia, submitted to Aeromonas hydrophila, were investigated. Thus, 280 Nile tilapia (initial weight = 50 ± 5,7 g/fish), were allocated in 35 tanks (250 l), eight fish/tank. The experiment was conducted in a completely randomized design, characterized by seven treatments, diet control and the other with propolis supplementation of 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0% with five repetitions. The fish were weighed at the beginning and final of experimental for evaluating the performance parameters. After thirty days, 16 fishes/treatment were anesthetized with benzocaine (1.0g/15L of water), and collected blood to evaluation to haematological and immunological parameters, characterizing the period before to bacterial challenge. The parameters analized were: red blood cell count , haematocrit, haemoglobin, mean corpuscular volume (MCV), mean corpuscular haemoglobin concentration (MCHC), and hydrogen peroxide and nitric oxide (NO). Then, eight fish of each treatment were inoculated with intraperitoneal injection with culture of A. Hydrophila containing 2.0x107UFC/mL, and transferred to twenty eight plastic tanks (40L), and two fishes per tank. The same haematological and immunological parameters were evaluated after fifteen days. The results showed that high levels of crude propolis influence at decrease of weight gain and Hb, an increase of NO. Comparing the moments, was observed that after challenge the fishes showed low value of Htc, MCV, neutrophils and NO, also high value of MCHC. It was concluded that crude propolis affect the growth and health of the-Nile tilapia / Doutor

Orientador: Marlene Aparecida Schiavinato / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-11T08:26:31Z (GMT). No. of bitstreams: 1 PinzonTorres_JavierAlberto_D.pdf: 1532904 bytes, checksum: 9f5bb662cffba52fd08c58de00484c25 (MD5) Previous issue date: 2008 / Resumo: As grandes quantidades de poluentes gasosos que as áreas urbano-industriais emitem contribuem para a degradação de ecossistemas com subseqüentes declínios na vegetação. A fotossíntese é um dos primeiros processos alterados pela ação destes poluentes e o dióxido de enxofre (SO₂), por ser um dos poluentes aéreos mais freqüentes e nocivos, afeta drasticamente a atividade fotossintética e causa graves injúrias nos tecidos foliares. O SO₂ difunde-se tão prontamente quanto o CO₂ para o interior da folha através dos estômatos e, na fase aquosa da câmara subestomática, se solubiliza formando bisulfito e sulfito, que são espécies iônicas de ação oxidante altamente agressiva para a célula. O sulfito, se não for rapidamente oxidado para sulfato em presença da luz, compete com o CO₂ tornando-se um inibidor da fixação fotossintética, enquanto que o bisulfito pode reagir com aldeídos e cetonas, formando hidroxisulfonatos, que são inibidores de várias enzimas. Durante a oxidação aeróbica dos sulfitos e bisulfitos há aumento da concentração de radicais livres que, se não forem exauridos rapidamente por enzimas de destoxificação, podem causar peroxidação dos ácidos graxos insaturados, ruptura dos lipídeos hidroperóxidos e co-oxidação das clorofilas nos cloroplastos. A resistência da planta à ação tóxica do SO₂ sugere vários mecanismos, dentre as quais se destacam: a redução da absorção de SO₂ por meio do fechamento estomático; a oxidação do sulfito a sulfato com posterior armazenamento do sulfato no vacúolo e incorporação ao metabolismo normal sob forma orgânica; e a eliminação pelo sistema antioxidante das peroxidases e da superóxido dismutase. Se um excesso de enxofre é absorvido e a concentração de tióis aumenta, o enxofre poderá ser acumulado na forma de glutationa, que é um tripeptídeo com uniões sulfídricas, ou os excessos de grupos sulfídricos e sulfitos poderiam ser convertidos em sulfetos ou perdidos na forma de ácido sulfídrico, por meio de trocas gasosas, retirando enxofre do metabolismo da planta. O objetivo do trabalho foi estudar os mecanismos imediatos de defesa e recuperação da taxa fotossintética em plantas de Centrolobium tomentosum sob condições de estresse induzido por SO₂, antes que algum tipo de injúria foliar ou fitotoxicidade, como clorose ou necrose foliar, se tornassem visíveis. Para isto, uma câmara de indução foi especialmente construída, de modo a permitir coletar amostras foliares in vivo, enquanto o estresse estava acontecendo. Dentro da câmara de indução foi colocada uma espécie nativa, Centrolobium tomentosum, que havia sido mantida até então sob condições ambientais naturais, na casa de vegetação do Departamento de Fisiologia Vegetal (Unicamp). Os ensaios com SO₂ foram realizados na câmara de indução, em sistema fechado, e esta foi mantida em uma câmara de crescimento, sob condições controladas de luz, temperatura e umidade. Plantas de C. tomentosum entre oito meses e um ano de idade foram submetidas a diferentes concentrações de SO₂ com a finalidade de determinar a concentração mínima de SO₂ capaz de induzir, na taxa fotossintética, a sucessão das fases características de uma dinâmica de estresse. Foram utilizadas cinco plantas diferentes por cada concentração de SO₂ aplicada e registrou-se a taxa fotossintética utilizando um Sistema Portátil de Análise de Gases por Infravermelho (IRGA). Nas mesmas folhas foram analisados antioxidantes do tipo não enzimático (pigmentos fotossintéticos e ácido ascórbico) e antioxidantes do tipo enzimático (superóxido dismutase e glutationa redutase). Foi determinado que a concentração mínima para induzir a dinâmica de estresse em plantas de C. tomentosum foi de 258,07 g SO₂ m­­­ֿ³, que equivale a uma concentração muito alta com relação às concentrações máximas recomendadas pelas organizações governamentais para o controle de poluição de ar. A sucessão de fases na taxa fotossintética foram as seguintes: - Taxa fotossintética antes da aplicação do SO&#8322: nesta fase, a taxa fotossintética registrou uma média de 4,4 μmol CO&#8322 m­­­­­ֿ² s­­­­­ֿ¹. Foram tomadas amostras foliares, cujas análises corresponderam ao controle. - Fase de alarme: iniciada imediatamente após a aplicação de 258,07 g SO₂ m­­­ֿ³ e caracterizada por uma queda abrupta na taxa fotossintética de 92%. Posteriormente, veio o estresse propriamente dito, com registros muito baixos na taxa fotossintética. - Fase de restituição: na qual se observou a recuperação paulatina da taxa fotossintética. Fase de resistência: na qual, após 9 h da exposição ao SO₂, a taxa fotossintética registrou recuperação de 50%. Após 24 h do ensaio ter sido iniciado, a taxa fotossintética registrou os valores iniciais correspondentes ao controle, ou seja, uma recuperação completa. Em todas as fases, com exceção da fase de restituição, foram tomadas amostras foliares. Não foram observados sintomas de clorose ou necrose nas folhas de C. tomentosum após a exposição ao SO₂ e as análises químicas dos pigmentos fotossintéticos corroboram esta observação. Porém, nas fases de estresse e de recuperação completa, os teores de carotenóides aumentaram com relação ao controle. O incremento do ácido ascórbico teve a mesma tendência do que o dos carotenóides nas fases de estresse e de recuperação completa. A atividade da superóxido dismutase aumentou significativamente na fase de estresse, enquanto que a atividade da glutationa redutase aumentou significativamente na fase de recuperação completa. A dinâmica de estresse e o mecanismo imediato de destoxificação em plantas de C. tomentosum submetidas a 258,07 g SO₂ m­­­ֿ³ sugerem que efetivamente houve um estresse oxidativo, que foi superado da seguinte maneira: na fase de alarme, o sulfito reagiu com a ribulose bisfosfato antes que fosse foto-oxidado para sulfato. Isto explica a inibição da carboxilação, com a queda abrupta da taxa fotossintética. Os oxi-radicais livres citotóxicos gerados nos cloroplastos, como conseqüência da foto-oxidação dos sulfitos, foram exauridos rapidamente pelo aumento, na fase de estresse, dos carotenóides e do ácido ascórbico e pelo aumento da atividade da superóxido dismutase. Porém, o enxofre proveniente do SO₂ não foi imediatamente acumulado na forma de glutationa. Isso somente ocorreu quando a planta recuperou completamente a taxa fotossintética. Desta maneira, verificou-se que C. tomentosum é uma espécie resistente que poderia ser utilizada em espaços onde as emissões de SO₂ são altas, como nas indústrias químicas, petroquímicas, siderúrgicas e de fertilizantes, dentre outras. / Abstract: Large quantities of gaseous pollutants emited by urban-industrial areas emit contribute to the degradation of ecosystems with subsequent declines in vegetation. The photosynthesis is one of the first processes altered by the action of these pollutants and sulphur dioxide (SO₂), as one of the most common and harmful air pollutants, drastically affect the photosynthetic activity and cause serious injuries in the leaf tissue. The SO₂ diffuses itself as promptly as the CO₂ into the leaf through the stomata, and in the aqueous phase of the substomatal cavity it solubilizes forming bisulphite and sulphite, which are ionic species of highly aggressive oxidant action to the cell. Sulphites, if it is not quickly oxidized to sulphate in the presence of light, it competes with CO₂ becoming an inhibitor of photosynthetic fixation, while the bisulphite can react with aldehydes and ketones, forming hidroxisulphonates, which are inhibitors of several enzymes. During the aerobics oxidation of sulphites and bisulphites there are increase in the concentration of free radicals that cause peroxidation of unsaturated fatty acids, lipid hydroperoxides and disruption of co-oxidation of chlorophylls in chloroplasts, if not quickly eliminated by enzymes of detoxification. The resistance of the plant to the toxic action of SO₂ suggests several mechanisms, among which stand out: the reduction of SO₂ absorption through the stomatal closure, the oxidation of sulphite to sulphate with the subsequent storage of sulphate inside the vacuole and the incorporation in the normal metabolism in organic way, and the scavenging by antioxidant system of peroxidases and superoxide dismutase. If an excess of sulphur is absorbed and the concentration of thiols increase, the sulphur may be accumulated in the form of glutathione, which is a tripeptide with sulphidric bindings, or the excesses of sulphidric groups and sulphites could be converted into sulfides or lost in the form of sulphidric acid, through gas exchange, removing the sulphur from the metabolism of the plant. The objective was to study the mechanisms of immediate protection and recovery of the photosynthetic rate in plants of Centrolobium tomentosum under conditions of stress induced by SO₂, before some kind of leaf injury or phytotoxicity, like chlorosis or leaf necrosis, became visible. For this, an induction chamber has specially been constructed to allow collect of leaf samples in vivo, while the stress was happening. Inside the induction chamber it was put a native species, Centrolobium tomentosum, which had been kept under natural environmental conditions at a greenhouse of the Department of Plant Physiology (UNICAMP). The tests were conducted with SO₂ in the chamber of induction, in a closed system, and this was maintained in a growth chamber, under controlled light, temperature and humidity conditions. Plants of C. tomentosum between eight months and one year old were submited to different concentrations of SO₂ in order to determine the lowest concentration of SO₂ capable to induce, in the photosynthetic rate, the succession of phases that are characteristics of a dynamics of stress. There were used five different plants for each concentration of SO₂ applied, and the photosynthetic rate was recorded using a Portable System for Analysis of gases by Infrared (IRGA). In the same leaves, non-enzymatic antioxidants (photosynthetic pigments and ascorbic acid) and enzymatic antioxidant (superoxide dismutase and glutathione reductase) were analysed. It was determined that the lowest concentration to induce the dynamics of stress in plants of C. tomentosum was 258,07 g SO₂ m­­­ֿ³, which represents a very high concentration regarding the maximum concentrations recommended by governmental organizations to the air pollution control. The succession of phases in the photosynthetic rate was as follows: - Photosynthetic rate before the implementation of SO₂: at this stage, the photosynthetic rate recorded an average of 4.4 μmol CO₂ m­­­ֿ² sֿ¹. Leaf samples were taken, whose analyses correponded to the control. - Phase of alarm: it has begun immediately after the injection of 258,07 g SO₂ m­ֿ³ characterized by the sharp fall in the photosynthetic rate of 92%. Then the stress itself begun, with very low records in photosynthetic rate. - Phase of restitution: in which there was observed the gradual recovery of the photosynthetic rate. - Phase of resistance: in which, after 9 hours of exposure to SO₂, the photosynthetic rate recorded recovery of 50%. After 24 hours of the beginning of the assay, the photosynthetic rate recorded the initial value corresponding to the control, that is, a complete recovery. In all stages, except in the stage of restitution, leaf samples were taken. There were no symptoms of chlorosis or necrosis in the leaves of C. tomentosum after exposure to SO₂ and chemical analysis of photosynthetic pigments corroborate to this observation. However, in stages of stress and complete recovery, the levels of carotenoids increased in relation to the control. The increase of ascorbic acid had the same trend of that of carotenoids in stages of stress and complete recovery. The activity of superoxide dismutase increased significantly in the stage of stress, while the activity of glutathione reductase increased significantly during the complete recovery. The dynamics of stress and the immediate mechanism of detoxification in plants of C. tomentosum submitted to 258,07 g SO₂ m­­­­­ֿ³ suggest that effectively there was actually an oxidative stress, which was overcame in the following way: during the alarm, the sulfite reacted with ribulose bisphosphate before the photo-oxidation to sulphate. This explains the inhibition of carboxylation, with a sharp decrease in the photosynthetic rate. The citotoxic free radicals generated in the chloroplasts, as a result of the photo-oxidation of sulphites, were quickly scavenged by the increase, in the phase of stress, of carotenoids and ascorbic acid and the increasing activity of superoxide dismutase. However, the sulphur from SO₂ has not been immediately accumulated in the form of glutathione. It only occurred when the plant recovered completely the photosynthetic rate. Thus, it was found that C. tomentosum is a resistant species that could be used in areas where SO₂ emissions are high, as in the chemical, petrochemical, steel and fertilizers factories, among others. / Doutorado / Doutor em Biologia Vegetal

No description available.

No description available.

Indiana University-Purdue University Indianapolis (IUPUI) / Brain responds to an array of diverse challenges that are defined as either exteroceptive stress, involving cognitive processing of sensory information from the external environment and or interoceptive stress, detected through sensory neural or chemical cues from the internal environment. The physiological response to most stresses consists of autonomic responses that are essential for animal survival in the face of a threatening circumstance. However, it is known that exposition to continuous situations of stress is involved in the development of a series of diseases such as hypertension, myocardial infarction and panic syndrome. Several studies have shown that cells in a specific area of the brain, the dorsomedial hypothalamus (DMH), are involved in the response produced during emotional stress. However, the role of glutamatergic transmission in the DMH in the increase in body temperature induced by experimental stress has not been examined. Research findings thus far indicate that neurons in the DMH play a role in thermoregulation and that local glutamate receptors may be involved. The hypothesis of this thesis is that activity at ionotropic glutamate receptors in the DMH is necessary for the thermogenic response induced by experimental stress. In the present work, microinjections of kynurenate, an excitatory amino acid antagonist, NBQX (2, 3-dihydroxy-6-nitro-7-sulfamoyl-benzo[f]quinoxaline-2,3-dione), an AMPA/kainate receptor antagonist, DL-2-amino-5-phosphonovaleric acid (APV), an NMDA receptor antagonist, and a mixture of NBQX and APV, were delivered to the DMH before exposure to experimental stress. The stress paradigms used include models for exteroceptive stress and interoceptive stress. The results show that inhibition of both NMDA and non-NMDA receptors is necessary to abolish the thermogenic response produced by all stress paradigms tested. Furthermore, there appears to be a difference in the degree of attenuation of the thermogenic response produced by either inhibition of NMDA receptors or non-NMDA receptors. Together these results support a definite role for ionotropic glutamate receptors within DMH region in the thermogenic response to stress. These results also finally show that the DMH is involved in all the major physiological stress responses including increase in plasma ACTH, increase in heart rate, blood pressure and now temperature as well.