Drosophila embryonic dorsal-ventral (D-V) polarity is defined by the expression of the gene pipe in the ventral cells of the follicular epithelium surrounding the developing oocyte. pipe encodes a sulfotransferase that transfers sulfate groups to several protein components of the vitelline membrane layer of the eggshell, including Vitelline Membrane-Like protein (VML). These sulfated proteins represent a ventral cue embedded in the eggshell, which, during embryogenesis, leads to the spatially-restricted activation of a serine protease cascade involving Gastrulation Defective (GD), Snake and Easter. Several important pieces of information missing from our understanding of Drosophila D-V patterning include the structures of the carbohydrates borne by the Pipe targets that represent the direct substrates for Pipe and how the Pipe-sulfated ventral cue triggers the spatially-regulated activation of the serine protease cascade. Two major goals of my studies on VML are to elucidate the structures of Pipe-sulfated carbohydrates associated with VML and to identify proteins that interact with VML in a Pipe-dependent manner. To achieve the first goal, I explored different purification systems to isolate VML and eventually found a way of partially purifying VML from Drosophila ovaries. Mass spectrometric analysis of the purified VML is underway to determine the carbohydrate structures on VML and the sites of Pipe-mediated sulfation. Future experiments will involve identification of putative enzymes responsible for the glycosylation of VML and examination of their requirements in D-V patterning. To identify interacting partners of VML, a strategy combining in vivo biotinylation of VML, reversible protein crosslinking and Streptavidin purification of crosslinked complexes will be used. In the second section of my studies, I have demonstrated that VML bearing a biotin acceptor peptide (BAP) tag can be efficiently biotinylated in vivo by co-expressing it with a biotin protein ligase BirA in the follicle cells. As an extension of the application of the approach, I also show that the Torso-like protein, which is localized to the poles of the vitelline membrane and whose polar localization is crucial for Drosophila terminal patterning, can also be biotinylated in vivo when the BAP-tagged protein is co-expressed with BirA in the follicle cells. / text

No description available.

Research Doctorate - Doctor of Philosophy (PhD) / World shark populations are declining rapidly from the increased demand for shark meat and fins and from their capture as by-catch. Techniques to accurately and reliably estimate the age of elasmobranchs are required to understand life history and develop management strategies. Although some biological information exists for the harvested species, few of the many shark species caught as by-catch have been investigated. In the waters of New South Wales, Australia, the Port Jackson shark (Heterodontus portusjacksoni) is a non-targeted species, however it is a major contributor to the elasmobranch by-catch in the bottom trawl and prawn fisheries. Although some biological and ecological information exists on Port Jackson sharks from New South Wales, there is no understanding of suitable techniques to age this species and of the age structure of the New South Wales’ population. Hence, the main purpose for the present study was to determine a suitable technique to age Port Jackson sharks and thereby provide essential age and growth data for its future management, sustainable use and conservation. This study consisted of research into: (1) the macroscopic anatomy of the vertebral centra and dorsal spines from 652 H. portusjacksoni to explore their suitability as ageing structures; (2) a comparison of whole and sectioned vertebral centra and of whole and sectioned dorsal spines for ageing; (3) validation of the annual formation of growth bands; (4) a comparison of the effect of prior experience on readers’ ability to count annual growth bands in vertebral centra; and (5) the development of age-growth models for the New South Wales’ population of H. portusjacksoni. Two types of vertebral centra (trunk and caudal vertebrae) were found in the vertebral column. Both vertebrae consisted of a centrum, 2 ribs, 4 neural arches, basiopophyses and neural foramen and decreased in size from anterior to posterior. A strong linear relationship was identified between vertebral diameter (VD) and fork length (FL). Each dorsal spine was positioned anterior to the dorsal fin and consisted of a stem and the cap. A strong linear relationships were identified between spine base width (SBW) and FL. The existence of alternating opaque and translucent band pairs in both structures further suggested they may be suitable for ageing purposes. Validation (calcein and oxytetracycline injections, marginal increment analysis, and centrum edge analysis) confirmed that translucent band pairs were formed during the winter (September-November) and were annual in both vertebral centra and dorsal spines. Whole and sectioned vertebral centra and dorsal spines were individually examined to determine which method best estimated the age. Although both methods had individual low reading bias and high precision, there was a difference between the two methods. The average bias between the two methods using vertebral centra was -0.158 ±0.05 and the coefficient of variance (CV) was 92.32% for females and -0.157 ±0.03 and CV was 56.95% for males. This indicated that sectioned vertebral centra returned higher ages than whole vertebral centra. When comparing whole dorsal spine age estimates to sectioned dorsal spines, there was an average bias between methods of -0.22 ±0.026 and a low precision 73.09%. Again indicating that sectioned dorsal spines returned higher ages than whole dorsal spines. A comparison of ages estimated from sectioned vertebral centra and sectioned dorsal spines showed that vertebral centra aged older than dorsal spines. Although the two structures each had low reading bias and high reading precision, there were differences between the two structures. The average bias between the two structures was -0.4 ±0.03 and the CV was low (74.7%), indicating that there was a significant difference in age derived from the two structures. Therefore, great caution should be taken when choosing which structure to use for age estimation. Ages of sharks estimated from the recommended sectioned vertebral centra ranged from 0.2 to 32.5 years for females and 0.2 to 23.8 years for males. Four different growth models were compared using both sectioned vertebral centra and sectioned dorsal spines to estimate the best suitable growth curve. Out of the 4 growth models the Gompertz Growth Function (GGF) best described the growth of H. portusjacksoni. von Bertalanffy growth parameters estimated from ageing data using the GGF for females were t0 = 2.584 yr, k = 0.111, L∞ = 1134.1 mm FL, and for males t0 = 1.629 yr, k = 0.131, L∞ = 1012.9 mm FL. This indicates that H. portusjacksoni has a slow growth rate and a longer life span than most other elasmobranch species. The effect of reader’s experience on the bias and precision of age estimates of sectioned vertebral centra was determined in an experiment that compared the author (an experienced vertebral centra reader) with an experienced fish otolith reader, two readers recently trained in reading vertebral centra (but lacking experience), and two untrained and inexperienced readers. Bias and precision were determined for each reader from two ageing trials with the same structure three months apart. Between-trials bias for each reader (except the author)ranged from 0.033 to 0.13 and precision ranged from 8.2 to 19.5%, while the author had low bias 0.006 and high precision 1.1%. When comparing all the readers with the author, bias ranged from 0.033 to 0.13 with an 8.2 to 19.5% precision for trial one, and 0.017 to 0.5 with precision between 2.5 to 5.4% in trial two. The age-bias plots comparing the two trials all indicated that only the author was consistent. And the age-bias plots between the author and the other readers all indicated that neither experience in ageing teleost otoliths or limited training in ageing enhanced the bias or precision compared to inexperienced elasmobranch agers.

Research Doctorate - Doctor of Philosophy (PhD) / World shark populations are declining rapidly from the increased demand for shark meat and fins and from their capture as by-catch. Techniques to accurately and reliably estimate the age of elasmobranchs are required to understand life history and develop management strategies. Although some biological information exists for the harvested species, few of the many shark species caught as by-catch have been investigated. In the waters of New South Wales, Australia, the Port Jackson shark (Heterodontus portusjacksoni) is a non-targeted species, however it is a major contributor to the elasmobranch by-catch in the bottom trawl and prawn fisheries. Although some biological and ecological information exists on Port Jackson sharks from New South Wales, there is no understanding of suitable techniques to age this species and of the age structure of the New South Wales’ population. Hence, the main purpose for the present study was to determine a suitable technique to age Port Jackson sharks and thereby provide essential age and growth data for its future management, sustainable use and conservation. This study consisted of research into: (1) the macroscopic anatomy of the vertebral centra and dorsal spines from 652 H. portusjacksoni to explore their suitability as ageing structures; (2) a comparison of whole and sectioned vertebral centra and of whole and sectioned dorsal spines for ageing; (3) validation of the annual formation of growth bands; (4) a comparison of the effect of prior experience on readers’ ability to count annual growth bands in vertebral centra; and (5) the development of age-growth models for the New South Wales’ population of H. portusjacksoni. Two types of vertebral centra (trunk and caudal vertebrae) were found in the vertebral column. Both vertebrae consisted of a centrum, 2 ribs, 4 neural arches, basiopophyses and neural foramen and decreased in size from anterior to posterior. A strong linear relationship was identified between vertebral diameter (VD) and fork length (FL). Each dorsal spine was positioned anterior to the dorsal fin and consisted of a stem and the cap. A strong linear relationships were identified between spine base width (SBW) and FL. The existence of alternating opaque and translucent band pairs in both structures further suggested they may be suitable for ageing purposes. Validation (calcein and oxytetracycline injections, marginal increment analysis, and centrum edge analysis) confirmed that translucent band pairs were formed during the winter (September-November) and were annual in both vertebral centra and dorsal spines. Whole and sectioned vertebral centra and dorsal spines were individually examined to determine which method best estimated the age. Although both methods had individual low reading bias and high precision, there was a difference between the two methods. The average bias between the two methods using vertebral centra was -0.158 ±0.05 and the coefficient of variance (CV) was 92.32% for females and -0.157 ±0.03 and CV was 56.95% for males. This indicated that sectioned vertebral centra returned higher ages than whole vertebral centra. When comparing whole dorsal spine age estimates to sectioned dorsal spines, there was an average bias between methods of -0.22 ±0.026 and a low precision 73.09%. Again indicating that sectioned dorsal spines returned higher ages than whole dorsal spines. A comparison of ages estimated from sectioned vertebral centra and sectioned dorsal spines showed that vertebral centra aged older than dorsal spines. Although the two structures each had low reading bias and high reading precision, there were differences between the two structures. The average bias between the two structures was -0.4 ±0.03 and the CV was low (74.7%), indicating that there was a significant difference in age derived from the two structures. Therefore, great caution should be taken when choosing which structure to use for age estimation. Ages of sharks estimated from the recommended sectioned vertebral centra ranged from 0.2 to 32.5 years for females and 0.2 to 23.8 years for males. Four different growth models were compared using both sectioned vertebral centra and sectioned dorsal spines to estimate the best suitable growth curve. Out of the 4 growth models the Gompertz Growth Function (GGF) best described the growth of H. portusjacksoni. von Bertalanffy growth parameters estimated from ageing data using the GGF for females were t0 = 2.584 yr, k = 0.111, L∞ = 1134.1 mm FL, and for males t0 = 1.629 yr, k = 0.131, L∞ = 1012.9 mm FL. This indicates that H. portusjacksoni has a slow growth rate and a longer life span than most other elasmobranch species. The effect of reader’s experience on the bias and precision of age estimates of sectioned vertebral centra was determined in an experiment that compared the author (an experienced vertebral centra reader) with an experienced fish otolith reader, two readers recently trained in reading vertebral centra (but lacking experience), and two untrained and inexperienced readers. Bias and precision were determined for each reader from two ageing trials with the same structure three months apart. Between-trials bias for each reader (except the author)ranged from 0.033 to 0.13 and precision ranged from 8.2 to 19.5%, while the author had low bias 0.006 and high precision 1.1%. When comparing all the readers with the author, bias ranged from 0.033 to 0.13 with an 8.2 to 19.5% precision for trial one, and 0.017 to 0.5 with precision between 2.5 to 5.4% in trial two. The age-bias plots comparing the two trials all indicated that only the author was consistent. And the age-bias plots between the author and the other readers all indicated that neither experience in ageing teleost otoliths or limited training in ageing enhanced the bias or precision compared to inexperienced elasmobranch agers.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 168-181).

A zona de cisalhamento Dorsal de Canguçu (ZCDC) é uma zona transcorrente levógira de escala crustal e direção preferencial NE, que condicionou o emplaçamento e deformação de suítes de granitóides do Cinturão Dom Feliciano ao final do Ciclo Brasiliano. Os diversos granitóides que compbe o Batólito de Pelotas podem ser divididos em pré, sin ou tardi a pós ZCDC (D2). Os metagranitóides pré-D2 do Complexo Canguçu e do Complexo Gnaissico Arroio dos Ratos são de caráter cálcio-alcalino e mostram-se deformados por um regime tangencial D com sentido dextrógiro de movimento. As estruturas lineares incluem lineaçe5es de estiramento, linea0es minerais e eixo de dobras com orientação preferencial L-W a NW e baixo caimento. Evidências microestruturais de mecanismos de plasticidade cristalina, como subgrãos e novos grãos em feldspatos, mostram que este regime ocorreu em condiOes metamórficas equivalentes às de fácies anfibolito. Os metagranitos sin-ZCDC são cálcio-alcalinos a cálcio-alcalinos alto potássio e peraluminosos, denominados de Quitéria e Arroio Francisquinho, respectivamente. Os metagranitos pré e sin D2 apresentam uma fonação milonítica homogênea precoce e são cortados por diversas faixas de cisalhamento -(D2) tardias, com a formação de rochas protomiloníticas, ortomiloniticas e ultramiloníticas. Mudanças no comportamento dos feldspatos de dúctil a frágil, bem como o aparecimento de uma assembléia mineral metamórfico-hidrotermal composta por albita, epidoto, mica branca, biotita e.ou clorita demostram que este regime tardi - D2 instalou-se predominantemente sob condiç3es retrogressivas "semelhantes" as de fácies xistos verdes. / The Dorsal de Canguçu (DCSZ) is a sinistral transcurent shear zone of crustal scale, with a NE trend. This zone has affected and controlled the emplacement of granitic rocks of Brasilian age. The granitic rocks related to the DCSZ may be divided in pre, sin or tardi to pos-tectonic (D2). The pre D2 metagranitoids, belonging to Canguçu Complex and Arroio dos Ratos gneissic Complex, have calc-alkaline character and were deformed during the DI tangencial regime with a E-W translation direction of rocks masses. That is characterized by dextral sense of moviment. Linear D structures include stretching and mineral lineations and fold axes with L-W to NW preferential orientation, and low plunge. Microstructural evidence of crystal plasticity, as subgrains and new grains in feldspars, show that Dl deformation occurred in metamorphic conditions equivalent to amphibolite facies. The sin-D2 (DCSZ) metagranitic rocks are calc-alkaline to high-K calc-alkaline and peraluminous (Quitéria and Arroio Francisquinho respectively). The pre and sin-D2 metagranitic rocks present an early homogenous mylonitic foliation and cut by several late discrete shear zones (D2), that produce protomylonites, orthomylonites and ultramylonites. The change in feldspat benavior, from ductile to brittle, and the formation of a metamorphic-hydrothermal mineral assemblage composed by albite, epidote, white mica, biotite and/or chlorite demostrate that this tardi-D2 deformation took place under predominantely retrogressive conditions (green schist facies).

A zona de cisalhamento Dorsal de Canguçu (ZCDC) é uma zona transcorrente levógira de escala crustal e direção preferencial NE, que condicionou o emplaçamento e deformação de suítes de granitóides do Cinturão Dom Feliciano ao final do Ciclo Brasiliano. Os diversos granitóides que compbe o Batólito de Pelotas podem ser divididos em pré, sin ou tardi a pós ZCDC (D2). Os metagranitóides pré-D2 do Complexo Canguçu e do Complexo Gnaissico Arroio dos Ratos são de caráter cálcio-alcalino e mostram-se deformados por um regime tangencial D com sentido dextrógiro de movimento. As estruturas lineares incluem lineaçe5es de estiramento, linea0es minerais e eixo de dobras com orientação preferencial L-W a NW e baixo caimento. Evidências microestruturais de mecanismos de plasticidade cristalina, como subgrãos e novos grãos em feldspatos, mostram que este regime ocorreu em condiOes metamórficas equivalentes às de fácies anfibolito. Os metagranitos sin-ZCDC são cálcio-alcalinos a cálcio-alcalinos alto potássio e peraluminosos, denominados de Quitéria e Arroio Francisquinho, respectivamente. Os metagranitos pré e sin D2 apresentam uma fonação milonítica homogênea precoce e são cortados por diversas faixas de cisalhamento -(D2) tardias, com a formação de rochas protomiloníticas, ortomiloniticas e ultramiloníticas. Mudanças no comportamento dos feldspatos de dúctil a frágil, bem como o aparecimento de uma assembléia mineral metamórfico-hidrotermal composta por albita, epidoto, mica branca, biotita e.ou clorita demostram que este regime tardi - D2 instalou-se predominantemente sob condiç3es retrogressivas "semelhantes" as de fácies xistos verdes. / The Dorsal de Canguçu (DCSZ) is a sinistral transcurent shear zone of crustal scale, with a NE trend. This zone has affected and controlled the emplacement of granitic rocks of Brasilian age. The granitic rocks related to the DCSZ may be divided in pre, sin or tardi to pos-tectonic (D2). The pre D2 metagranitoids, belonging to Canguçu Complex and Arroio dos Ratos gneissic Complex, have calc-alkaline character and were deformed during the DI tangencial regime with a E-W translation direction of rocks masses. That is characterized by dextral sense of moviment. Linear D structures include stretching and mineral lineations and fold axes with L-W to NW preferential orientation, and low plunge. Microstructural evidence of crystal plasticity, as subgrains and new grains in feldspars, show that Dl deformation occurred in metamorphic conditions equivalent to amphibolite facies. The sin-D2 (DCSZ) metagranitic rocks are calc-alkaline to high-K calc-alkaline and peraluminous (Quitéria and Arroio Francisquinho respectively). The pre and sin-D2 metagranitic rocks present an early homogenous mylonitic foliation and cut by several late discrete shear zones (D2), that produce protomylonites, orthomylonites and ultramylonites. The change in feldspat benavior, from ductile to brittle, and the formation of a metamorphic-hydrothermal mineral assemblage composed by albite, epidote, white mica, biotite and/or chlorite demostrate that this tardi-D2 deformation took place under predominantely retrogressive conditions (green schist facies).

A zona de cisalhamento Dorsal de Canguçu (ZCDC) é uma zona transcorrente levógira de escala crustal e direção preferencial NE, que condicionou o emplaçamento e deformação de suítes de granitóides do Cinturão Dom Feliciano ao final do Ciclo Brasiliano. Os diversos granitóides que compbe o Batólito de Pelotas podem ser divididos em pré, sin ou tardi a pós ZCDC (D2). Os metagranitóides pré-D2 do Complexo Canguçu e do Complexo Gnaissico Arroio dos Ratos são de caráter cálcio-alcalino e mostram-se deformados por um regime tangencial D com sentido dextrógiro de movimento. As estruturas lineares incluem lineaçe5es de estiramento, linea0es minerais e eixo de dobras com orientação preferencial L-W a NW e baixo caimento. Evidências microestruturais de mecanismos de plasticidade cristalina, como subgrãos e novos grãos em feldspatos, mostram que este regime ocorreu em condiOes metamórficas equivalentes às de fácies anfibolito. Os metagranitos sin-ZCDC são cálcio-alcalinos a cálcio-alcalinos alto potássio e peraluminosos, denominados de Quitéria e Arroio Francisquinho, respectivamente. Os metagranitos pré e sin D2 apresentam uma fonação milonítica homogênea precoce e são cortados por diversas faixas de cisalhamento -(D2) tardias, com a formação de rochas protomiloníticas, ortomiloniticas e ultramiloníticas. Mudanças no comportamento dos feldspatos de dúctil a frágil, bem como o aparecimento de uma assembléia mineral metamórfico-hidrotermal composta por albita, epidoto, mica branca, biotita e.ou clorita demostram que este regime tardi - D2 instalou-se predominantemente sob condiç3es retrogressivas "semelhantes" as de fácies xistos verdes. / The Dorsal de Canguçu (DCSZ) is a sinistral transcurent shear zone of crustal scale, with a NE trend. This zone has affected and controlled the emplacement of granitic rocks of Brasilian age. The granitic rocks related to the DCSZ may be divided in pre, sin or tardi to pos-tectonic (D2). The pre D2 metagranitoids, belonging to Canguçu Complex and Arroio dos Ratos gneissic Complex, have calc-alkaline character and were deformed during the DI tangencial regime with a E-W translation direction of rocks masses. That is characterized by dextral sense of moviment. Linear D structures include stretching and mineral lineations and fold axes with L-W to NW preferential orientation, and low plunge. Microstructural evidence of crystal plasticity, as subgrains and new grains in feldspars, show that Dl deformation occurred in metamorphic conditions equivalent to amphibolite facies. The sin-D2 (DCSZ) metagranitic rocks are calc-alkaline to high-K calc-alkaline and peraluminous (Quitéria and Arroio Francisquinho respectively). The pre and sin-D2 metagranitic rocks present an early homogenous mylonitic foliation and cut by several late discrete shear zones (D2), that produce protomylonites, orthomylonites and ultramylonites. The change in feldspat benavior, from ductile to brittle, and the formation of a metamorphic-hydrothermal mineral assemblage composed by albite, epidote, white mica, biotite and/or chlorite demostrate that this tardi-D2 deformation took place under predominantely retrogressive conditions (green schist facies).

Developing and applying pre-clinical tumour models in order to determine the mechanistic action of applied therapies is essential if we aim to improve antitumour strategies in the clinical setting. The chaotic nature of tumour vasculature impacts directly on the effectiveness of combined chemo-radiotherapy and antiangiogenic (AA) strategies and as such warrants closer study. This work looked at the effects of novel AAs combined with clinically relevant radiotherapy (RT) using both conventional murine xenograft growth delay studies and real-time imaging. The imaging methodology was the non-invasive Dorsal Window Chamber/Intra Vital Microscopy (DWC/IVM) model which allows the study of real-time vascular responses to these therapies. The DWC/IVM model was applied to determine whether the DNA repair inhibitors Nicotinamide, AG14361 and AGO14699 had additional modes of action which could contribute to tumour radioresistance/radiosensitivity. Using the DWC/IVM model a secondary quantifiable mechanistic function was determined where these drugs also increased tumour vessel permeability. The DWC/IVM model was also used to investigate the effects of AZD2171 and AZD6244 combined with radiotherapy. These agents can inhibit angiogenic signalling pathways and it was demonstrated that both drugs worked by reducing tumour microvascular density when used in combination with radiation. In studies looking at the influence of hypoxia inducible factor-1(HIF-1) on tumour response to radiation the DWC/IVM model provided measurable differences in the microvascular density between HIF-1 deficient and HIF-1 competent tumours. The DWC/IVM model allowed the direct visualisation and quantification of the less well developed vasculature in HIF-1 deficient tumours compared to that found in HIF-1 competent tumours. The results provide a mechanistic basis for understanding the improved response to radiotherapy of HIF-1 deficient tumours. By applying the DWC/IVM model to conventional murine xenograft models the DWC/IVM proved itself as a useful research tool where continuous real-time non-invasive measurements could be made without the need for large numbers of time points or laborious histological analysis.

O hipocampo dorsal (HD) é uma estrutura do sistema límbico que está envolvida em processos emocionais, de memória e aprendizado. Alem disso, o HD também exerce influência sobre a atividade autonômica. Durante situações aversivas pode se observar tanto respostas autonômicas (aumento da pressão arterial, frequência cardíaca e queda da temperatura cutânea) quanto comportamentais. O HD está envolvido com diversas alterações associadas a reações defensivas e apresenta conexões com diversas estruturas que modulam essas respostas, fazendo parte de uma via responsável por modular as respostas durante situações aversivas. São observadas aumentos nas respostas autonômicas durante o estresse por restrição (ER). Durante a atividade do HD está aumentada. Além disso, é possível observar aumento dos níveis de glutamato no HD. A ativação de receptores glutamatérgicos do tipo NMDA no sistema nervoso central aumenta a síntese de óxido nítrico (NO) por ativação da isoforma neuronial da óxido nítrico sintase (nNOS). Além disso, esta interação, NMDA/NO, no HD parece ser importante nas reações defensivas. Portanto, no presente estudo nós observamos que a administração de glutamato no HD promove aumentos do sistema cardiovascular, similares a aqueles observados durante situações de estresse. Estas respostas cardiovasculares são associadas com um aumento da atividade simpática. Além disso, os efeitos do glutamato foram inibidos pela administração do AP7, um antagonista NMDA, do N?-Propyl-L-Arginine, um inibidor da nNOS ou do Carboxy-PTIO(S)-3-carboxy-4- hydroxyphenylglicine, um sequestrador de NO. Finalmente, a administração destas drogas foi capaz de reduzir as respostas autonômicas causadas pelo ER. Portanto, nossos achados mostram que o sistema glutamatérgico presente no HD esta envolvido com a modulação autonômica através de receptores do tipo NMDA e a ativação de nNOS. Além disso, esta via NMDA/NO está envolvida na modulação autonômica durante situações de estresse. / The dorsal hippocampus (DH) is a structure of limbic system that is involved in emotional, leaning and memories process. Moreover, the DH also exerts influence on autonomic activity. During aversive situations it is possible observes autonomic responses (increase in blood pressure, heart rate and decrease in cutaneous temperature) associated to defensive behavioral. The DH is involved with alterations associated to defensive reactions and presents connections with several structures which modulate that responses, making part of a pathway involved with behavior and autonomic responses associated with aversive situations. Increase of autonomics responses are observed during restraint stress (RS). During RS the DH activity is increased. Moreover, it is possible observe increases in glutamate levels in DH. In central nervous system the activation of NMDA glutamatergic receptors increases the nitric oxide (NO) synthesis by activate the neuronal isoform of nitric oxide syntase (nNOS). Moreover, this interaction, NMDA/ NO, in the DH appears to important in the defensive reactions. Therefore, in the present work we observed that administration of glutamate in the DH promotes increases of cardiovascular system, similar those observed during stress situation. These cardiovascular responses were associate with an increase of sympathetic activity. Also, the glutamate effects were inhibited by administration of AP7, a NMDA antagonist, N?-Propyl-L-Arginine, a nNOS inhibitor, or Carboxy-PTIO(S)-3- carboxy-4-hydroxyphenylglicine, a NO scavenger. Finally, the administration of these drugs were able to reduces the autonomic responses evoked by RS. Therefore, our findings showed that glutamatergic system present in DH are involved with autonomic modulation through NMDA receptors and nNOS activation. Moreover, this NMDA/ NO is involved with autonomic modulation during stress situation.