RESUMO
INTRODUCTION: The adult brain of mammals preserves the capacity to generate new neurons from neural stem/progenitor cells. The new neurons become part of the already-existing networks by means of a process called 'neurogenesis in the adult brain', which is restricted to regions of the brain with a high degree of plasticity and which are associated to functions that are impaired in Alzheimer's disease. DEVELOPMENT: Despite increasing knowledge, there are still many questions surrounding these neurogenic phenomena, their regulation and their real therapeutic potential in cases of neurodegeneration such as the one referred to here. CONCLUSIONS: We have reviewed the subject of neurogenesis of the adult brain from both the pre-clinical point of view (experimental modelling) and the therapeutic perspective within the framework of Alzheimer's disease.
Assuntos
Doença de Alzheimer/terapia , Neurogênese/fisiologia , Doença de Alzheimer/fisiopatologia , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/fisiologia , Modelos Animais de Doenças , Hipocampo/citologia , Humanos , Neurônios/fisiologia , Transplante de Células-Tronco , Células-Tronco/fisiologiaRESUMO
Introducción. El trasplante es una de las alternativas para el tratamiento de enfermedades neurodegenerativas, y está encaminado hacia el reemplazo de las células perdidas durante el desarrollo de la enfermedad. Una fuente celular prometedora para el desarrollo de los trasplantes podrían ser las células mononucleadas de la médula ósea. Objetivo. Estudiar la capacidad de las células mononucleadas de la médula ósea de sobrevivir al trasplante y buscar un método que permita el seguimiento de estas células in vivo una vez implantadas. Materiales y métodos. Las células mononucleadas fueron extraídas del fémur de ratas mediante un gradiente de Ficoll-Hypaque. Las células objeto de estudio fueron modificadas genéticamente con un adenovirus que expresa la PFV o marcadas con el reactivo de Hoechst. Las células marcadas se implantaron en el estriado de ratas lesionadas con ácido quinolínico. Resultados. La viabilidad de las células modificadas genéticamente fue baja, mientras que la de las células marcadas con el reactivo de Hoechst fue superior al 90 por ciento. Las células implantadas sobrevivieron al trasplante al menos un mes y se dispersaron desde el sitio de entrada hacia el cuerpo calloso y la corteza. Conclusiones. Consideramos más ventajoso el uso del reactivo de Hoechst para el seguimiento de estas células in vivo. Las células mononucleadas tienen características que les permiten formar parte de las fuentes celulares candidatas para el tratamiento de las enfermedades neurodegenerativas(AU)
Introduction: Transplant is one of the alternatives available for the treatment of neurodegenerative diseases aimed at replacing the cells lost during the course of the disease. One promising source of cells for the development of transplants could be the mononucleate cells from bone marrow. AIMS. The purpose of this study was to study the capacity of bone marrow mononucleate cells to survive the transplant process, and to search for a method that enables tracking of these cells in vivo once they have been implanted. MATERIALS AND METHODS: Bone marrow mononucleate cells were extracted from the femur of rats by means of a Ficoll-Hypaque gradient. The cells under study were modified genetically with an adenovirus that expresses the PFV or which are marked with Hoechst dye. The marked cells were implanted in the striatum of rats with lesions caused by quinolinic acid. RESULTS: The viability of the genetically modified cells was low, whereas that of the cells marked with Hoechst dye was above 90percent. The implanted cells survived the transplant at least a month and dispersed away from the site of entry towards the corpus callosum and cortex. CONCLUSIONS: We consider that the use of Hoechst dye offers more advantages for tracking these cells in vivo. Mononucleate cells have a number of characteristics that allow them to be included as candidate sources of cells for the treatment of neurodegenerative diseases
Assuntos
Animais , Ratos , Células da Medula Óssea/citologia , Células da Medula Óssea/fisiologia , Transplante de Medula Óssea , Movimento Celular , Ácido Quinolínico/toxicidade , Córtex Visual/citologia , Córtex Visual , Córtex Visual/patologiaRESUMO
INTRODUCTION: Transplant is one of the alternatives available for the treatment of neurodegenerative diseases aimed at replacing the cells lost during the course of the disease. One promising source of cells for the development of transplants could be the mononucleate cells from bone marrow. AIMS. The purpose of this study was to study the capacity of bone marrow mononucleate cells to survive the transplant process, and to search for a method that enables tracking of these cells in vivo once they have been implanted. MATERIALS AND METHODS: Bone marrow mononucleate cells were extracted from the femur of rats by means of a Ficoll-Hypaque gradient. The cells under study were modified genetically with an adenovirus that expresses the PFV or which are marked with Hoechst dye. The marked cells were implanted in the striatum of rats with lesions caused by quinolinic acid. RESULTS: The viability of the genetically modified cells was low, whereas that of the cells marked with Hoechst dye was above 90%. The implanted cells survived the transplant at least a month and dispersed away from the site of entry towards the corpus callosum and cortex. CONCLUSIONS: We consider that the use of Hoechst dye offers more advantages for tracking these cells in vivo. Mononucleate cells have a number of characteristics that allow them to be included as candidate sources of cells for the treatment of neurodegenerative diseases.
Assuntos
Células da Medula Óssea , Transplante de Medula Óssea , Sobrevivência Celular , Ácido Quinolínico/toxicidade , Córtex Visual , Animais , Benzimidazóis/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/fisiologia , Movimento Celular , Corantes Fluorescentes/metabolismo , Masculino , Doenças Neurodegenerativas/terapia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Córtex Visual/citologia , Córtex Visual/efeitos dos fármacos , Córtex Visual/patologiaRESUMO
INTRODUCTION: The use of fresh foetal tissue in neurotransplants entails considerable problems of logistics that limit its clinical applicability, something that can be resolved by the development of optimal tissue storage procedures that do not affect in vivo viability and survival of dopamine. AIMS. To determine whether 7 days' hibernation affects the survival of mesencephalic tissue in vitro, and to compare it to fresh tissue. MATERIALS AND METHODS: The midbrains of rats were hibernated for 1, 3, 5 and 7 days at 4 degrees C. A cellular suspension was prepared for culture throughout a 7-day period. The number of TH+ cells present in the fresh and hibernated cultures was determined. RESULTS: The morphology of the hibernated and cultured dopaminergic neurons was very similar to that of the fresh cells. Comparing the viability of the hibernated and fresh cells did not reveal any significant differences. No significant differences between the numbers of TH+ neurons were observed at any of the hibernation times. The lowest rate of TH+ cell survival was reached at seven days' hibernation. Significant differences (p < 0.05) were found between the number of TH+ neurons for fresh and hibernated tissue. CONCLUSIONS: Hibernation at 4 degrees C for up to five days guarantees the survival of TH+ cells in vitro, but it is affected by longer times. This procedure could be considered useful for preserving human tissue in clinical transplant applications. These results refer to in vitro conditions; therefore, studies must be conducted to investigate the survival and functionality of hibernated and transplanted neurons in animal models to enable us to evaluate its applicability in neurorestorative therapy.
Assuntos
Transplante de Tecido Encefálico/métodos , Técnicas de Cultura de Células , Sobrevivência Celular , Dopamina/metabolismo , Transplante de Tecido Fetal/métodos , Neurônios , Animais , Forma Celular , Humanos , Mesencéfalo/citologia , Mesencéfalo/metabolismo , Neurônios/química , Neurônios/citologia , Neurônios/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo , Tirosina 3-Mono-Oxigenase/metabolismoRESUMO
El uso de tejido fetal fresco en el neurotrasplante presenta considerables dificultades logìsticas que limitan su aplicabilidad clìnica . Este aspecto podrìa solucionarse con el desarrollo de procedimientos optimos de almacenamiento del tejido que no afecten a la viabilidad y la supervivencia dopaminèrgica in vivo. Es objetivo del trabajao determinar si la hibernaciòn durante siete dìas influye sobre la supervivencia del tejido mesencefàlico in vitro y comparar el tejido hibernado con el fresco...(AU)
Assuntos
Humanos , Animais , Ratos , Transplante de Tecido Encefálico/métodos , Neurônios/citologia , Neurônios/fisiologia , Técnicas de Cultura de Células/métodos , Sobrevivência CelularRESUMO
INTRODUCTION: Most of the culture system for in vitro maintenance and neural differentiation of marrow stromal cells (MSCs) use synthetic media supplemented with 10 or 20% fetal bovine serum (FBS). Serum, however, is comprised of unknown quantities of undefined substances which could interfere the effect of exogenous substances on neural differentiation of MSCs. AIM. Here we describe survival of MSCs cultured in culture conditions where serum was reduced at 0.5 and 1% using Bottenstein and Sato's N2 formula (1979) and poly-L-lysine (PLL)-coated substrate. MATERIALS AND METHODS: Stromal cells isolated from rat femurs were cultivated in Dulbecco's modified Eagle medium at 10, 1, 0.5% FBS or in serum free medium containing N2 formula. In serum free medium or at low serum concentration culture surface was coated with PLL. Cell survival was determined by MTT method or by counting viable cells. RESULTS: Survival of MSCs cultured in N2 supplement was reduced at about 40% of that observed in 10% FBS containing medium. Under these conditions cell morphology was also affected. When N2 containing medium was supplemented with FBS at 0.5 or 1% a significant increase of survival with respect to that observed in N2-supplemented cultures was observed. Cells seeded on PLL-coated surface increased their survival by contrast with their homologous cultures seeded on uncoated surface. CONCLUSIONS: The culture system which combines N2 formula with FBS 1% and PLL-coated surface is useful for the maintenance of MSCs. These conditions offer advantages for the study of differentiation of these cells because they reduce the confounding influence of serum. The possible implication of this culture system for the study of neural differentiation by these cells is discussed.
Assuntos
Células da Medula Óssea/metabolismo , Técnicas de Cultura de Células , Meios de Cultura/química , Células Estromais/metabolismo , Animais , Células da Medula Óssea/citologia , Bovinos , Forma Celular , Sobrevivência Celular , Células Cultivadas , Meios de Cultura Livres de Soro , Ratos , Ratos Wistar , Células Estromais/citologiaRESUMO
Most of the culture system for in vitro maintenance and neural differentiation of marrow stromal cells (MSCs) use synthetic media supplemented with 10 or 20 percent fetal bovine serum (FBS). Serum, however, is comprised of unknown quantities of undefined substances which could interfere the effect of exogenous substances on neural differentiation of MSCs, AIM. Here we describe survival of MSCs cultured in culture conditions where serum was reduced at 0,5 and 1 percent using Bottenstein and Sato's N2 formula (1979) and poly-L-lysine (PLL)-coated substrate...(AU)
Assuntos
Animais , Ratos , Células da Medula Óssea , Técnicas de Cultura de Células , Meios de Cultura , Células EstromaisRESUMO
INTRODUCTION: A good deal of evidence currently exists to show that transplanting foetal mesencephalic tissue can produce symptomatic benefits both in patients and in disease models. Nevertheless, the technical and ethical difficulties involved in obtaining enough suitable foetal cerebral tissue have been a serious obstacle to its application. Stromal cells derived from bone marrow, due to their potential capacity to generate different types of cells, could be an ideal source of material for cell restoration in neurodegenerative diseases. AIMS: Our aim was to evaluate the effect of transplanting stromal cells derived from bone marrow on the behaviour of 6-OHDA rats, when they are inserted into the striatum. MATERIAL AND METHODS: In this study we used rats with a lesion in the substantia nigra induced by 6-hydroxydopamine, divided into several experimental groups. Rotary activity induced by D-amphetamine (5 mg/kg, intraperitoneally) was evaluated before and throughout the three months following the transplant in all the experimental groups, except in the group of healthy controls. Hemiparkinsonian rats received a total of 350 000 foetal ventral mesencephalic cells and 8 x 10(4) stromal cells/microL, which were implanted in the striatum. RESULTS AND CONCLUSIONS: Animals with stromal cells transplanted in the body of the striatum significantly reduced the number of turns induced by amphetamine (p < 0.05); yet this reduction was not greater than that induced by foetal mesencephalic cell transplants. We were also unable to demonstrate any significant improvement in the motor skills of the forelimbs.
Assuntos
Modelos Animais de Doenças , Doença de Parkinson/cirurgia , Células Estromais/transplante , Animais , Comportamento Animal , Masculino , Oxidopamina/administração & dosagem , Doença de Parkinson/etiologia , Ratos , Ratos WistarRESUMO
A good deal of evidence currently exists to show that transplanting foetal mesencephalic tissue can produce symptomatic benefits both in patients and in disease models. Nevertheless, the technical and ethical difficulties involved in obtaining enough suitable foetal cerebral tissue have been a serious obstacle to its application. Stromal cells derived from bone marrow, due to their potential capacity to generate different types of cells, could be an ideal source of material for cell restoration in neurodegenerative diseases. AIMS: Our aim was to evaluate the effect of transplanting stromal cells derived from bone marrow on the behaviour of 6-OHDA rats, when they are inserted into the striatum(AU)
Assuntos
Animais , Ratos , Modelos Animais de Doenças , Doença de Parkinson/cirurgia , Células Estromais/transplanteRESUMO
In embryonic mesencephalic transplant in patients with Parkinson s disease dopaminergic survival is low (5 10%), and for this reason the use of multiple donors has been considered. The difficulty of obtaining more tissue determines the need for a procedure that enables human nigral tissue to be stored for a time without affecting its physiological state in any significant way. This study was designed to determine whether hibernation of tissue fragments has any influence on viability, how the viability of the mesencephalic cells behaves after 7 days hibernation and the glutathione levels in the hibernated tissue (HT). The viability of the HT in pieces (82.37 2.12) was found to be higher than the value for the whole mesencephalon (70.29 3.43). Viability of the HT, seven days at 4 C, at different post dissociation times, did not differ significantly. Despite the significant differences found between hibernated and fresh tissue at t= 0, this procedure does not seem to affect the mesencephalic tissue in any significant way, as it conserved a 94% viability after hibernation. No evidence was found of increased glutathione content as an antioxidizing response to the damage that might be caused by hibernation. These results suggest that since hibernation does not have any significant effect on the state of the cells it could be considered a useful procedure for conserving tissue to be used in clinical transplants. Moreover, further research is needed on survival and functionality of hibernated cells after being transplanted into animal models in order to evaluate their potential for use in cell therapy.
Assuntos
Embrião de Mamíferos/fisiologia , Glutationa/metabolismo , Hibernação/fisiologia , Mesencéfalo/embriologia , Mesencéfalo/metabolismo , Neurônios/metabolismo , Doença de Parkinson/cirurgia , Animais , Modelos Animais de Doenças , Dopamina/metabolismo , Transplante de Tecido Fetal , Mesencéfalo/transplante , Neurônios/citologia , Neurônios/transplante , Ratos , Ratos Wistar , Substância Negra/metabolismo , Substância Negra/transplante , Fatores de TempoRESUMO
INTRODUCTION: The main strategy followed in neural transplants as a method of treatment for Parkinson s disease, both experimental and clinical, has been to introduce foetal mesencephalic cells into the target area: the striatum. However, when the dopaminergic cells in the substantia nigra degenerate, not only is the dopaminergic innervation of the striatum affected but also other nuclei: globus pallidus, substantia nigra, substantia nigra pars reticulata and subthalamic nucleus. A series of data from pharmacological and physiological studies offer strong evidence that the dopamine released in these nuclei may play an important role in regulating the output nuclei of the basal ganglia. AIM: To evaluate the effect of transplanting foetal mesencephalic cells on the behaviour of 6 OH DA rats when introduced into the striatum and the subthalamic nucleus. MATERIALS AND METHODS: 6 OH DA was used to induce lesions in the substantia nigra of rats, which were divided into several experimental groups. The rotating activity induced by D amphetamine (5 mg/kg, intraperitoneally) and apomorphine (0.05 mg/kg, subcutaneously) was evaluated before and three months after the transplant in all the experimental groups, except in the control group of healthy rats. The hemiparkinsonian rats received a total of 350,000 foetal ventral mesencephalic cells, which were implanted within small deposits in the striatum (8) and in the subthalamic nucleus (4). RESULTS AND CONCLUSIONS: Rotation induced by both drugs was significantly lower (p= 0.05) in animals that had had dopaminergic cells transplanted into the striatum body. No significant improvement in this behaviour was to be found when transplants were limited to just the subthalamus or, simultaneously, also to the striatum. A significant increase in rotating behaviour induced by apomorphine was observed in the group which received a transplant in just the subthalamus.
Assuntos
Transplante de Tecido Encefálico , Transplante de Tecido Fetal , Mesencéfalo/citologia , Neurônios/transplante , Doença de Parkinson/terapia , Núcleo Subtalâmico/cirurgia , Córtex Visual/cirurgia , Adrenérgicos/farmacologia , Animais , Antiparkinsonianos/farmacologia , Apomorfina/farmacologia , Comportamento Animal , Dextroanfetamina/farmacologia , Modelos Animais de Doenças , Dopamina/metabolismo , Masculino , Mesencéfalo/embriologia , Mesencéfalo/transplante , Neurônios/citologia , Neurônios/efeitos dos fármacos , Oxidopamina/toxicidade , Ratos , Ratos Wistar , Rotação , Núcleo Subtalâmico/patologia , Córtex Visual/patologiaRESUMO
Introducción. La principal estrategia de trasplante neural como tratamiento de la enfermedad de Parkinson, tanto experimental como clínico, ha sido colocar las células mesencefálicas fetales en su principal blanco: el estriado. Sin embargo, cuando las células dopaminérgicas de la sustancia negra degeneran, no sólo se afecta la inervación dopaminérgica del estriado; por el contrario, la inervación de otros núcleos, como el globo pálido, sustancia negra parte reticulada y núcleo subtalámico, también se afectan. Una serie de datos provenientes de estudios farmacológicos y fisiológicos proveen de fuertes evidencias acerca de que la dopamina liberada en estos núcleos puede desempeñar un papel importante en la regulación de los núcleos de salida de los ganglios basales. Objetivo. El objetivo principal de este estudio fue evaluar el efecto del trasplante de células mesencefálicas fetales sobre la conducta de ratas-6-OH-DA, cuando el mismo se coloca en el estriado y el núcleo subtalámico. Materiales y métodos. Se utilizaron ratas con lesión de la sustancia negra inducida por la 6-OHDA,divididas en varios grupos experimentales. La actividad rotatoria inducida por D-anfetamina (5 mg/kg, intraperitonealmente) y apomorfina (0,05 mg/kg, subcutáneamente) se evaluó antes y en los tres meses posteriores al trasplante en todos los grupos experimentales, excepto en el grupo de controles sanos. Las ratas hemiparkinsonianas recibieron un total de 350.000 células de mesencéfalo ventral fetal, que se implantaron en pequeños depósitos en el estriado (8) y en el núcleo subtalámico (4). Resultados y conclusiones. Los animales con trasplante de células dopaminérgicas en el cuerpo estriado redujeron significativamente el número de vueltas inducido por ambas drogas (p=0,05). No fue posible demostrar mejoría significativa de estas conductas cuando los trasplantes se colocaron sólo en el subtálamo o en este núcleo, simultáneamente al estriado. Se observó un incremento significativo en la conducta de giro inducida por apomorfina en el grupo con trasplante aislado en subtálamo neural(AU)
Assuntos
Doença de Parkinson , Núcleo SubtalâmicoRESUMO
Introducción. El factor de crecimiento epidérmico (FCE) ejerce un efecto neurotrófico o mitogénico sobre diferentes poblaciones celulares en el sistema nervioso, lo que está modulado por el estadío de desarrollo celular y el microambiente donde se desarrollan las células. Objetivo y métodos. En este trabajo se describe la acción del FCE sobre las células del estriado embrionario en un sistema de cultivo disociado de neuronas y glias. El cultivo de células se preparó a partir de embriones de ratas de 16-17 días. En el sistema empleado la población celular fue cultivada durante 20-24 horas en un medio que contenía suero y posteriormente se sutituyó este por una mezcla de nutrientes definidos y se trató con 20 ng/ml de FCE durante 6 días. Resultados y conclusiones. La sustitución del suero en este período inicial de desarrollo provocó una disminución apreciable de las células vivas en los cultivos tratados y en los controles. Las células sobrevivientes estaban representadas mayoritariamente por precursores celulares teniendo en cuenta sus características morfológicas y su capacidad proliferativa. El efecto del FCE se manifestó en un aumento del número de células y se demostró un estímulo de la proliferación de los precursores neuronales y de los astrocitos. La actividad específica de la colina acetiltransferasa determinada en los cultivos a los 16 días evidenció la diferenciación de una subpoblación neuronal colinérgica, la cual respondió al tratamiento con el factor de crecimiento nervioso con un aumento de la actividad de esta enzima (AU)
Assuntos
Técnicas In Vitro , Fator de Crescimento Epidérmico , Técnicas de Cultura de Células , Fatores de Crescimento Neural , Técnicas de CulturaAssuntos
Animais , Potenciação de Longa Duração , Demência , Modelos Animais de Doenças , EnvelhecimentoRESUMO
Introducción. El factor de crecimiento epidérmico (FCE) ejerce un efecto neurotrófico o mitogénico sobre diferentes poblaciones celulares en el sistema nervioso, lo que está modulado por el estadío de desarrollo celular y el microambiente donde se desarrollan las células. Objetivo y métodos. En este trabajo se describe la acción del FCE sobre las células del estriado embrionario en un sistema de cultivo disociado de neuronas y glias. El cultivo de células se preparó a partir de embriones de ratas de 16-17 días. En el sistema empleado la población celular fue cultivada durante 20-24 horas en un medio que contenía suero y posteriormente se sutituyó este por una mezcla de nutrientes definidos y se trató con 20 ng/ml de FCE durante 6 días. Resultados y conclusiones. La sustitución del suero en este período inicial de desarrollo provocó una disminución apreciable de las células vivas en los cultivos tratados y en los controles. Las células sobrevivientes estaban representadas mayoritariamente por precursores celulares teniendo en cuenta sus características morfológicas y su capacidad proliferativa. El efecto del FCE se manifestó en un aumento del número de células y se demostró un estímulo de la proliferación de los precursores neuronales y de los astrocitos. La actividad específica de la colina acetiltransferasa determinada en los cultivos a los 16 días evidenció la diferenciación de una subpoblación neuronal colinérgica, la cual respondió al tratamiento con el factor de crecimiento nervioso con un aumento de la actividad de esta enzima (AU)
Assuntos
Técnicas In Vitro , Fator de Crescimento Epidérmico , Técnicas de Cultura de Células , Fatores de Crescimento Neural , Técnicas de CulturaRESUMO
Introducción. El factor de crecimiento epidérmico (FCE) ejerce un efecto neurotrófico o mitogénico sobre diferentes poblaciones celulares en el sistema nervioso, lo que está modulado por el estadío de desarrollo celular y el microambiente donde se desarrollan las células. Objetivo y métodos. En este trabajo se describe la acción del FCE sobre las células del estriado embrionario en un sistema de cultivo disociado de neuronas y glias. El cultivo de células se preparó a partir de embriones de ratas de 16-17 días. En el sistema empleado la población celular fue cultivada durante 20-24 horas en un medio que contenía suero y posteriormente se sutituyó este por una mezcla de nutrientes definidos y se trató con 20 ng/ml de FCE durante 6 días. Resultados y conclusiones. La sustitución del suero en este período inicial de desarrollo provocó una disminución apreciable de las células vivas en los cultivos tratados y en los controles. Las células sobrevivientes estaban representadas mayoritariamente por precursores celulares teniendo en cuenta sus características morfológicas y su capacidad proliferativa. El efecto del FCE se manifestó en un aumento del número de células y se demostró un estímulo de la proliferación de los precursores neuronales y de los astrocitos. La actividad específica de la colina acetiltransferasa determinada en los cultivos a los 16 días evidenció la diferenciación de una subpoblación neuronal colinérgica, la cual respondió al tratamiento con el factor de crecimiento nervioso con un aumento de la actividad de esta enzima (AU)
Assuntos
Técnicas In Vitro , Fator de Crescimento Epidérmico , Técnicas de Cultura de Células , Fatores de Crescimento Neural , Técnicas de CulturaRESUMO
INTRODUCTION: Epidermic growth factor (EGF) has a neurotrophic mitogenic effect on different cell populations in the nervous system. This is modulated by the stage of development and microenvironment of the cells. OBJECTIVE AND METHODS: In this paper we describe the action of EGF on embryonic striatum cells of a culture system dissociated from neurons and glias. The cell culture is prepared from 16-17 day rat embryos. In the system used, the cell population was cultured for 20-24 hours in a medium containing serum. This medium was later replaced by a mixture of specific nutrients and treated for 6 days with 20 mg/ml of EGF. RESULTS AND CONCLUSIONS: The substitution of serum during the initial period of development led to an appreciable reduction in the living cells in the treated cultures and in the controls. The surviving cells were mainly cellular precursors, taking into account their morphological characteristics and capacity for proliferation. The effect of EGF was seen in an increase in the number of cells and was shown to be a stimulus to the proliferation of neuronal and astrocyte precursors. The specific activity of choline acetyl-transferases determined in the cultures at 16 days showed differentiation of a cholinergic neurons subpopulation, which responded to treatment with nerve growth factor with an increase in the activity of this enzyme.
Assuntos
Corpo Estriado/citologia , Corpo Estriado/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Substâncias de Crescimento/farmacologia , Animais , Anticorpos Monoclonais , Morte Celular , Divisão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Células Cultivadas/efeitos dos fármacos , Colina O-Acetiltransferase/metabolismo , Fibras Colinérgicas/efeitos dos fármacos , Fibras Colinérgicas/enzimologia , Corpo Estriado/enzimologia , Fatores de Crescimento Neural/farmacologia , Ratos , Ratos WistarRESUMO
Introducción. El factor de crecimiento epidérmico (FCE) ejerce un efecto neurotrófico o mitogénico sobre diferentes poblaciones celulares en el sistema nervioso, lo que está modulado por el estadío de desarrollo celular y el microambiente donde se desarrollan las células. Objetivo y métodos. En este trabajo se describe la acción del FCE sobre las células del estriado embrionario en un sistema de cultivo disociado de neuronas y glias. El cultivo de células se preparó a partir de embriones de ratas de 16-17 días. En el sistema empleado la población celular fue cultivada durante 20-24 horas en un medio que contenía suero y posteriormente se sutituyó este por una mezcla de nutrientes definidos y se trató con 20 ng/ml de FCE durante 6 días. Resultados y conclusiones. La sustitución del suero en este período inicial de desarrollo provocó una disminución apreciable de las células vivas en los cultivos tratados y en los controles. Las células sobrevivientes estaban representadas mayoritariamente por precursores celulares teniendo en cuenta sus características morfológicas y su capacidad proliferativa. El efecto del FCE se manifestó en un aumento del número de células y se demostró un estímulo de la proliferación de los precursores neuronales y de los astrocitos. La actividad específica de la colina acetiltransferasa determinada en los cultivos a los 16 días evidenció la diferenciación de una subpoblación neuronal colinérgica, la cual respondió al tratamiento con el factor de crecimiento nervioso con un aumento de la actividad de esta enzima