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Consumer and shear force evaluation of steaks from the M. Serratus ventralisBagley, Jason Lee 25 April 2007 (has links)
An in-home evaluation of steaks from the M. Serratus ventralis was conducted to
determine consumer acceptance. Steaks were also evaluated by Warner-Bratzler shear
force (WBS) evaluations. Steaks from the M. Serratus ventralis were either blade
tenderized, injected with a salt, phosphate, and papain solution, or served as a control.
Consumers (n = 136) were not given a specific method of cookery, but were asked to
document cooking method and degree of doneness, overall-like, tenderness desirability,
tenderness of cut, juiciness desirability, juiciness of cut, flavor desirability, and flavor
intensity. When cooked on the grill, in the oven, or in a skillet, injected steaks received
the highest (P < 0.05) ratings for tenderness. Furthermore, consumers rated injected and
blade tenderized steaks higher (P<0.05) for overall like when they were cooked on the
grill to a higher degree of doneness. Oven cooked steaks that were injected, rated higher
(P<0.05) than blade tenderized steaks for juiciness. When cooked on the grill, juiciness
ratings were also higher (P<0.05) for injected steaks compared to control steaks.
Moreover, injected steaks had significantly lower (P<0.05) WBS values when compared
to blade tenderized and control steaks. Overall, ratings for all steaks were adequate,
confirming the M. Serratus ventralis as a potential high quality steak for use in the retail
market.
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Tinktūros Neuroventralis 1, skystojo ekstrakto Ventralis ir tablečių Ventralis technologijos ir jų vertinimas / Technologies and valuation of The tincture neuroventralis 1, Liquid extract ventralis and Tablets ventralisVelžienė, Saulė 11 October 2005 (has links)
1. Relevance of the work
First medicine used by man was of herbal origin, i.e. prepared from plants, their parts and mixtures. After thousands of years, these preparations have not lost their relevance. Increasingly more and more clinical research is done on verification of efficiency and safety of herbal medicine, whereas methods of modern analysis help to ensure their quality and stability. This allows to objectively determine the potential of herbal medicine use, to foresee their possible side effects and to warn against their interaction with other drugs. It is essential that medicinal plants and their parts should be treated as a whole of biologically active substances. A lot of resources are allocated annually to the development of new herbal preparations and research of new plants, analysis of their chemical composition, pharmacological toxicological action, and interaction of plants with other medicinal drugs. By interacting with regulatory systems of the organism, herbal drugs inhibit or stimulate them and primarily affect subjective symptoms. Herbal medicine must be individually prescribed according to the peculiarities of the patient’s ailment and body. Herbal medicine can evoke reactions of the body, which depend on individual characteristics of the patient and on effect of the herbal drugs. There must be no doubts, though, that this medicine is better tolerated and its side effects are considerably milder that those of synthetic preparations. This can be... [to full text]
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Estrutura de habitat, diversidade e comportamento da avifauna em sistemas de silvicultura em floresta ombrófila mistaLima, André de Mendonça January 2012 (has links)
A silvicultura está em franco progresso na América do Sul e as áreas de plantio têm ocupado cada vez mais territórios. No Brasil o conhecimento dos efeitos desta atividade sobre a fauna e flora nativas ainda está em formação e poucos estudos tem sido realizados na Floresta Ombrófila Mista. Os capítulos 1 e 2 discorrem sobre aspectos teóricos envolvidos na elaboração do estudo e sobre a descrição da região/área estudada, respectivamente. No capítulo 3 foi efetuado estudo sobre como o estabelecimento de espécies em plantios comerciais de Pinus elliottii e Araucaria angustifolia afetam a riqueza, densidade e composição de plantas lenhosas nativas e quais características das espécies colonizadoras são selecionadas nestes ambientes. Não houve diferença na riqueza rarefeita encontrada entre os tratamentos amostrados, contudo a densidade e a composição de espécies foram diferentes. As características de dispersão dos frutos foram diferentes entre os tratamentos e entre os plantios exóticos e nativos, com maior frequência de zoocoria ocorrendo nos plantios de P. elliottii. No capítulo 4 foi desenvolvido um estudo para verificar se a riqueza, a densidade, a composição e parâmetros de diversidade da avifauna são afetados por variáveis ambientais estruturais de plantios nativos e exóticos de diferentes idades e com e sem sub-bosque. A riqueza rarefeita, a densidade e a diversidade de aves foi mais elevada em floresta nativa e plantios com sub-bosque do que em plantios sem sub-bosque. Conforme a análise de correlação canônica houve a formação de três grupos definidos pelos parâmetros fitossociológicos: (1) plantios de P. elliotti sem sub-bosque, (2) plantios de P. elliottii com sub-bosque e (3) plantios de A. angustifolia e floresta nativa. Nos capítulos 4 e 5 existe a indicação de que a distribuição das espécies de plantas lenhosas de sub-bosque e de aves dos plantios é aninhada, onde as assembleias encontradas nos plantios são subgrupos da assembleia observada em ambiente florestal nativo. O desenvolvimento do capítulo 5 foi baseado nas táticas de forrageamento empregadas para a captura de presas por Phylloscartes ventralis nos diferentes plantios trabalhados. O comportamento de forrageio de P. ventralis foi diferente entre as áreas amostradas, onde as principais alterações foram relacionadas a manobras de ataque a presas, ao ângulo e o substrato de forrageio, a altura e a localização horizontal onde as presas foram capturadas. Na ordenação os plantios de P. elliottii com sub-bosque e A. angustifolia aparecem junto com as áreas de floresta nativa indicando que houve poucas modificações no comportamento de forrageio entre estas áreas quando comparadas a plantios de P. elliottii sem sub-bosque. A partir dos resultados obtidos foi realizado o capítulo 6 onde se reúnem todas as considerações e conclusões obtidas. Os resultados indicam que existe alteração quanto aos parâmetros de vegetação, avifauna e comportamento quando se comparam a floresta nativa e os plantios de espécies nativas e exóticas. Fica evidente a importância de utilização de espécies nativas como alternativa a espécies exóticas em áreas de silvicultura. Outra característica importante para implementação de medidas de mitigação aos impactos desta atividade econômica é a possibilidade de manutenção do sub-bosque em áreas de plantios comerciais. / Silviculture has been in sheer progress in South America and the planting areas have increasingly taken up new territories. In Brazil knowledge of the effects of this activity on native flora and fauna is still being built and few studies have been conducted in the Araucaria Forest. Chapters 1 and 2 present theoretical aspects involved in preparing the study and the description of the region / area studied, respectively. In chapter 3 a study was conducted on how the establishment of species in Pinus elliottii and Araucaria angustifolia commercial plantations affects the richness, density and composition of native woody plants and which characteristics of the colonizing species are selected in such environments. No difference in rarefied richness was found between the treatments sampled, but the density and composition of the species were different. The characteristics of fruit dispersion were different between the treatments and between exotic and native plantations, with higher incidence of zoochory in P. elliottii plantations. Chapter 4 presents the study carried out to verify whether the avifauna’s richness, density, composition and parameters of diversity are affected by structural environmental variables of native and exotic plantations of different ages and with and without understory. The rarefied richness, density and diversity of birds were higher in native forest and in plantations with understory than in plantations without understory. According to canonical correlation analysis, there was the formation of three groups defined by phytosociological parameters: (1) P. elliotti plantations without understory, (2) P. elliottii plantations with understory and (3) A. angustifolia and native forest plantations. Chapters 4 and 5 indicate that the distribution of species of understory woody plants and of plantation birds is nested, the assemblies found in plantations being subsets of the assembly observed in native forest environment. The development of chapter 5 was based on the foraging tactics employed in prey capture by Phylloscartes ventralis in the different plantations in study. The foraging behavior of P. ventralis was different in the sampled areas, the chief alterations being related to prey attack maneuvers, foraging angle and substrate, height and horizontal location where prey was captured. In ordination, P. elliottii plantations with understory and A. angustifolia rank along with the native forest areas, which indicates that there were few modifications in foraging behavior between these areas as compared to P. elliottii plantations without understory. From the results obtained chapter 6 was created, gathering all the considerations and conclusions made. The results indicate that there is alteration regarding parameters of vegetation, avifauna and behavior when comparing native forest and plantations of native and exotic species. This evidences the importance of employing native species as an alternative to exotic ones in silviculture areas. Another important feature in implementing measures for mitigating the impacts of this economic activity is the possibility of maintaining the understory in commercial plantation areas.
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Estrutura de habitat, diversidade e comportamento da avifauna em sistemas de silvicultura em floresta ombrófila mistaLima, André de Mendonça January 2012 (has links)
A silvicultura está em franco progresso na América do Sul e as áreas de plantio têm ocupado cada vez mais territórios. No Brasil o conhecimento dos efeitos desta atividade sobre a fauna e flora nativas ainda está em formação e poucos estudos tem sido realizados na Floresta Ombrófila Mista. Os capítulos 1 e 2 discorrem sobre aspectos teóricos envolvidos na elaboração do estudo e sobre a descrição da região/área estudada, respectivamente. No capítulo 3 foi efetuado estudo sobre como o estabelecimento de espécies em plantios comerciais de Pinus elliottii e Araucaria angustifolia afetam a riqueza, densidade e composição de plantas lenhosas nativas e quais características das espécies colonizadoras são selecionadas nestes ambientes. Não houve diferença na riqueza rarefeita encontrada entre os tratamentos amostrados, contudo a densidade e a composição de espécies foram diferentes. As características de dispersão dos frutos foram diferentes entre os tratamentos e entre os plantios exóticos e nativos, com maior frequência de zoocoria ocorrendo nos plantios de P. elliottii. No capítulo 4 foi desenvolvido um estudo para verificar se a riqueza, a densidade, a composição e parâmetros de diversidade da avifauna são afetados por variáveis ambientais estruturais de plantios nativos e exóticos de diferentes idades e com e sem sub-bosque. A riqueza rarefeita, a densidade e a diversidade de aves foi mais elevada em floresta nativa e plantios com sub-bosque do que em plantios sem sub-bosque. Conforme a análise de correlação canônica houve a formação de três grupos definidos pelos parâmetros fitossociológicos: (1) plantios de P. elliotti sem sub-bosque, (2) plantios de P. elliottii com sub-bosque e (3) plantios de A. angustifolia e floresta nativa. Nos capítulos 4 e 5 existe a indicação de que a distribuição das espécies de plantas lenhosas de sub-bosque e de aves dos plantios é aninhada, onde as assembleias encontradas nos plantios são subgrupos da assembleia observada em ambiente florestal nativo. O desenvolvimento do capítulo 5 foi baseado nas táticas de forrageamento empregadas para a captura de presas por Phylloscartes ventralis nos diferentes plantios trabalhados. O comportamento de forrageio de P. ventralis foi diferente entre as áreas amostradas, onde as principais alterações foram relacionadas a manobras de ataque a presas, ao ângulo e o substrato de forrageio, a altura e a localização horizontal onde as presas foram capturadas. Na ordenação os plantios de P. elliottii com sub-bosque e A. angustifolia aparecem junto com as áreas de floresta nativa indicando que houve poucas modificações no comportamento de forrageio entre estas áreas quando comparadas a plantios de P. elliottii sem sub-bosque. A partir dos resultados obtidos foi realizado o capítulo 6 onde se reúnem todas as considerações e conclusões obtidas. Os resultados indicam que existe alteração quanto aos parâmetros de vegetação, avifauna e comportamento quando se comparam a floresta nativa e os plantios de espécies nativas e exóticas. Fica evidente a importância de utilização de espécies nativas como alternativa a espécies exóticas em áreas de silvicultura. Outra característica importante para implementação de medidas de mitigação aos impactos desta atividade econômica é a possibilidade de manutenção do sub-bosque em áreas de plantios comerciais. / Silviculture has been in sheer progress in South America and the planting areas have increasingly taken up new territories. In Brazil knowledge of the effects of this activity on native flora and fauna is still being built and few studies have been conducted in the Araucaria Forest. Chapters 1 and 2 present theoretical aspects involved in preparing the study and the description of the region / area studied, respectively. In chapter 3 a study was conducted on how the establishment of species in Pinus elliottii and Araucaria angustifolia commercial plantations affects the richness, density and composition of native woody plants and which characteristics of the colonizing species are selected in such environments. No difference in rarefied richness was found between the treatments sampled, but the density and composition of the species were different. The characteristics of fruit dispersion were different between the treatments and between exotic and native plantations, with higher incidence of zoochory in P. elliottii plantations. Chapter 4 presents the study carried out to verify whether the avifauna’s richness, density, composition and parameters of diversity are affected by structural environmental variables of native and exotic plantations of different ages and with and without understory. The rarefied richness, density and diversity of birds were higher in native forest and in plantations with understory than in plantations without understory. According to canonical correlation analysis, there was the formation of three groups defined by phytosociological parameters: (1) P. elliotti plantations without understory, (2) P. elliottii plantations with understory and (3) A. angustifolia and native forest plantations. Chapters 4 and 5 indicate that the distribution of species of understory woody plants and of plantation birds is nested, the assemblies found in plantations being subsets of the assembly observed in native forest environment. The development of chapter 5 was based on the foraging tactics employed in prey capture by Phylloscartes ventralis in the different plantations in study. The foraging behavior of P. ventralis was different in the sampled areas, the chief alterations being related to prey attack maneuvers, foraging angle and substrate, height and horizontal location where prey was captured. In ordination, P. elliottii plantations with understory and A. angustifolia rank along with the native forest areas, which indicates that there were few modifications in foraging behavior between these areas as compared to P. elliottii plantations without understory. From the results obtained chapter 6 was created, gathering all the considerations and conclusions made. The results indicate that there is alteration regarding parameters of vegetation, avifauna and behavior when comparing native forest and plantations of native and exotic species. This evidences the importance of employing native species as an alternative to exotic ones in silviculture areas. Another important feature in implementing measures for mitigating the impacts of this economic activity is the possibility of maintaining the understory in commercial plantation areas.
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Estrutura de habitat, diversidade e comportamento da avifauna em sistemas de silvicultura em floresta ombrófila mistaLima, André de Mendonça January 2012 (has links)
A silvicultura está em franco progresso na América do Sul e as áreas de plantio têm ocupado cada vez mais territórios. No Brasil o conhecimento dos efeitos desta atividade sobre a fauna e flora nativas ainda está em formação e poucos estudos tem sido realizados na Floresta Ombrófila Mista. Os capítulos 1 e 2 discorrem sobre aspectos teóricos envolvidos na elaboração do estudo e sobre a descrição da região/área estudada, respectivamente. No capítulo 3 foi efetuado estudo sobre como o estabelecimento de espécies em plantios comerciais de Pinus elliottii e Araucaria angustifolia afetam a riqueza, densidade e composição de plantas lenhosas nativas e quais características das espécies colonizadoras são selecionadas nestes ambientes. Não houve diferença na riqueza rarefeita encontrada entre os tratamentos amostrados, contudo a densidade e a composição de espécies foram diferentes. As características de dispersão dos frutos foram diferentes entre os tratamentos e entre os plantios exóticos e nativos, com maior frequência de zoocoria ocorrendo nos plantios de P. elliottii. No capítulo 4 foi desenvolvido um estudo para verificar se a riqueza, a densidade, a composição e parâmetros de diversidade da avifauna são afetados por variáveis ambientais estruturais de plantios nativos e exóticos de diferentes idades e com e sem sub-bosque. A riqueza rarefeita, a densidade e a diversidade de aves foi mais elevada em floresta nativa e plantios com sub-bosque do que em plantios sem sub-bosque. Conforme a análise de correlação canônica houve a formação de três grupos definidos pelos parâmetros fitossociológicos: (1) plantios de P. elliotti sem sub-bosque, (2) plantios de P. elliottii com sub-bosque e (3) plantios de A. angustifolia e floresta nativa. Nos capítulos 4 e 5 existe a indicação de que a distribuição das espécies de plantas lenhosas de sub-bosque e de aves dos plantios é aninhada, onde as assembleias encontradas nos plantios são subgrupos da assembleia observada em ambiente florestal nativo. O desenvolvimento do capítulo 5 foi baseado nas táticas de forrageamento empregadas para a captura de presas por Phylloscartes ventralis nos diferentes plantios trabalhados. O comportamento de forrageio de P. ventralis foi diferente entre as áreas amostradas, onde as principais alterações foram relacionadas a manobras de ataque a presas, ao ângulo e o substrato de forrageio, a altura e a localização horizontal onde as presas foram capturadas. Na ordenação os plantios de P. elliottii com sub-bosque e A. angustifolia aparecem junto com as áreas de floresta nativa indicando que houve poucas modificações no comportamento de forrageio entre estas áreas quando comparadas a plantios de P. elliottii sem sub-bosque. A partir dos resultados obtidos foi realizado o capítulo 6 onde se reúnem todas as considerações e conclusões obtidas. Os resultados indicam que existe alteração quanto aos parâmetros de vegetação, avifauna e comportamento quando se comparam a floresta nativa e os plantios de espécies nativas e exóticas. Fica evidente a importância de utilização de espécies nativas como alternativa a espécies exóticas em áreas de silvicultura. Outra característica importante para implementação de medidas de mitigação aos impactos desta atividade econômica é a possibilidade de manutenção do sub-bosque em áreas de plantios comerciais. / Silviculture has been in sheer progress in South America and the planting areas have increasingly taken up new territories. In Brazil knowledge of the effects of this activity on native flora and fauna is still being built and few studies have been conducted in the Araucaria Forest. Chapters 1 and 2 present theoretical aspects involved in preparing the study and the description of the region / area studied, respectively. In chapter 3 a study was conducted on how the establishment of species in Pinus elliottii and Araucaria angustifolia commercial plantations affects the richness, density and composition of native woody plants and which characteristics of the colonizing species are selected in such environments. No difference in rarefied richness was found between the treatments sampled, but the density and composition of the species were different. The characteristics of fruit dispersion were different between the treatments and between exotic and native plantations, with higher incidence of zoochory in P. elliottii plantations. Chapter 4 presents the study carried out to verify whether the avifauna’s richness, density, composition and parameters of diversity are affected by structural environmental variables of native and exotic plantations of different ages and with and without understory. The rarefied richness, density and diversity of birds were higher in native forest and in plantations with understory than in plantations without understory. According to canonical correlation analysis, there was the formation of three groups defined by phytosociological parameters: (1) P. elliotti plantations without understory, (2) P. elliottii plantations with understory and (3) A. angustifolia and native forest plantations. Chapters 4 and 5 indicate that the distribution of species of understory woody plants and of plantation birds is nested, the assemblies found in plantations being subsets of the assembly observed in native forest environment. The development of chapter 5 was based on the foraging tactics employed in prey capture by Phylloscartes ventralis in the different plantations in study. The foraging behavior of P. ventralis was different in the sampled areas, the chief alterations being related to prey attack maneuvers, foraging angle and substrate, height and horizontal location where prey was captured. In ordination, P. elliottii plantations with understory and A. angustifolia rank along with the native forest areas, which indicates that there were few modifications in foraging behavior between these areas as compared to P. elliottii plantations without understory. From the results obtained chapter 6 was created, gathering all the considerations and conclusions made. The results indicate that there is alteration regarding parameters of vegetation, avifauna and behavior when comparing native forest and plantations of native and exotic species. This evidences the importance of employing native species as an alternative to exotic ones in silviculture areas. Another important feature in implementing measures for mitigating the impacts of this economic activity is the possibility of maintaining the understory in commercial plantation areas.
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The Neural Substrate of Sex Pheromone Signalling in Male Goldfish (Carassius auratus)Lado, Wudu E. 26 October 2012 (has links)
The transmission of sex pheromone-mediated signals is essential for goldfish reproduction. However, the neural pathways underlying this reproductive signalling pathway in the goldfish brain is not well described. Lesioning experiments have shown previously that two brain areas, the preoptic area (POA) and the ventral telencephali pars ventralis (Vv) in particular, are important for reproduction. We used patch clamp electrophysiology to study the electrical activities of POA and Vv neurons. Based on the intrinsic properties of these neurons, we suggest there are five different functional classes of POA neurons and a single class of Vv neurons. In addition, by electrically stimulating the olfactory bulb (OB), we were able to show that this primary sensory structure makes monosynaptic glutamatergic connections with both POA and Vv neurons. While electrophysiology measures signalling events occurring at short time scales on the order of milliseconds to minutes, we were also interested in studying sex pheromone signalling in the goldfish brain over a long time scale. Thus, we describe changes in gene expression in male goldfish exposed to waterborne sex pheromones (17alpha,20beta dihydroxy-4-pregene-3-one and Prostaglandin-F2alpha) over 6 hours. We perform cDNA microarrays on Prostaglandin-F2alpha-treated fish to study the rapid modulation of transcription and define the signalling pathways affected. Our microarrays showed that 71 genes were differentially regulated (67 up and 4 down). Through gene ontology enrichment analysis, we found that these genes were involved in various biological processes such as RNA processing, neurotransmission, neuronal development, apoptosis, cellular metabolism and sexual reproduction. RT-PCRs were performed to validate our microarrays and to facilitate direct comparisons of the effects of the two sex pheromones, 17alpha,20beta dihydroxy-4-pregene-3-one and Prostaglandin-F2alpha. By combining electrophysiology and gene expression analyses, we were able to study sex-pheromone signalling on two different time scales. One short, occurring on the order of milliseconds to minutes, that involves electrical activities in the brain through the glutamatergic amino-3-hydroxy-5-methylisoxazole-4-propionate and N-methyl-D-aspartate receptors; and the other long occurring several hours later that involves changes in the gene expression levels of calmodulin and ependymin among other genes underlying neuroplasticity. Reproductive neuroplasticity in the goldfish may therefore require the activation of glutamatergic receptors which then activate downstream signals like calmodulin and ependymin to transform the sex pheromones-mediate signal into gene expression.
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The Neural Substrate of Sex Pheromone Signalling in Male Goldfish (Carassius auratus)Lado, Wudu E. 26 October 2012 (has links)
The transmission of sex pheromone-mediated signals is essential for goldfish reproduction. However, the neural pathways underlying this reproductive signalling pathway in the goldfish brain is not well described. Lesioning experiments have shown previously that two brain areas, the preoptic area (POA) and the ventral telencephali pars ventralis (Vv) in particular, are important for reproduction. We used patch clamp electrophysiology to study the electrical activities of POA and Vv neurons. Based on the intrinsic properties of these neurons, we suggest there are five different functional classes of POA neurons and a single class of Vv neurons. In addition, by electrically stimulating the olfactory bulb (OB), we were able to show that this primary sensory structure makes monosynaptic glutamatergic connections with both POA and Vv neurons. While electrophysiology measures signalling events occurring at short time scales on the order of milliseconds to minutes, we were also interested in studying sex pheromone signalling in the goldfish brain over a long time scale. Thus, we describe changes in gene expression in male goldfish exposed to waterborne sex pheromones (17alpha,20beta dihydroxy-4-pregene-3-one and Prostaglandin-F2alpha) over 6 hours. We perform cDNA microarrays on Prostaglandin-F2alpha-treated fish to study the rapid modulation of transcription and define the signalling pathways affected. Our microarrays showed that 71 genes were differentially regulated (67 up and 4 down). Through gene ontology enrichment analysis, we found that these genes were involved in various biological processes such as RNA processing, neurotransmission, neuronal development, apoptosis, cellular metabolism and sexual reproduction. RT-PCRs were performed to validate our microarrays and to facilitate direct comparisons of the effects of the two sex pheromones, 17alpha,20beta dihydroxy-4-pregene-3-one and Prostaglandin-F2alpha. By combining electrophysiology and gene expression analyses, we were able to study sex-pheromone signalling on two different time scales. One short, occurring on the order of milliseconds to minutes, that involves electrical activities in the brain through the glutamatergic amino-3-hydroxy-5-methylisoxazole-4-propionate and N-methyl-D-aspartate receptors; and the other long occurring several hours later that involves changes in the gene expression levels of calmodulin and ependymin among other genes underlying neuroplasticity. Reproductive neuroplasticity in the goldfish may therefore require the activation of glutamatergic receptors which then activate downstream signals like calmodulin and ependymin to transform the sex pheromones-mediate signal into gene expression.
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The Neural Substrate of Sex Pheromone Signalling in Male Goldfish (Carassius auratus)Lado, Wudu E. January 2012 (has links)
The transmission of sex pheromone-mediated signals is essential for goldfish reproduction. However, the neural pathways underlying this reproductive signalling pathway in the goldfish brain is not well described. Lesioning experiments have shown previously that two brain areas, the preoptic area (POA) and the ventral telencephali pars ventralis (Vv) in particular, are important for reproduction. We used patch clamp electrophysiology to study the electrical activities of POA and Vv neurons. Based on the intrinsic properties of these neurons, we suggest there are five different functional classes of POA neurons and a single class of Vv neurons. In addition, by electrically stimulating the olfactory bulb (OB), we were able to show that this primary sensory structure makes monosynaptic glutamatergic connections with both POA and Vv neurons. While electrophysiology measures signalling events occurring at short time scales on the order of milliseconds to minutes, we were also interested in studying sex pheromone signalling in the goldfish brain over a long time scale. Thus, we describe changes in gene expression in male goldfish exposed to waterborne sex pheromones (17alpha,20beta dihydroxy-4-pregene-3-one and Prostaglandin-F2alpha) over 6 hours. We perform cDNA microarrays on Prostaglandin-F2alpha-treated fish to study the rapid modulation of transcription and define the signalling pathways affected. Our microarrays showed that 71 genes were differentially regulated (67 up and 4 down). Through gene ontology enrichment analysis, we found that these genes were involved in various biological processes such as RNA processing, neurotransmission, neuronal development, apoptosis, cellular metabolism and sexual reproduction. RT-PCRs were performed to validate our microarrays and to facilitate direct comparisons of the effects of the two sex pheromones, 17alpha,20beta dihydroxy-4-pregene-3-one and Prostaglandin-F2alpha. By combining electrophysiology and gene expression analyses, we were able to study sex-pheromone signalling on two different time scales. One short, occurring on the order of milliseconds to minutes, that involves electrical activities in the brain through the glutamatergic amino-3-hydroxy-5-methylisoxazole-4-propionate and N-methyl-D-aspartate receptors; and the other long occurring several hours later that involves changes in the gene expression levels of calmodulin and ependymin among other genes underlying neuroplasticity. Reproductive neuroplasticity in the goldfish may therefore require the activation of glutamatergic receptors which then activate downstream signals like calmodulin and ependymin to transform the sex pheromones-mediate signal into gene expression.
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