Study of sexual dimorphism in the neurochemical and neuroendocrine response to stress in adult rats exposed prenatally to D-amphetamine

Las anfetaminas son psicoestimulantes que actúan sobre los sistemas monoaminérgicos con un mecanismo de acción similar al de la cocaína. Su consumo ha aumentado en el país en el embarazo. Las drogas psicoactivas pueden atravesar fácilmente la barrera placentaria y llegar al feto para afectar el normal desarrollo cerebral. La exposición a dosis bajas de anfetaminas o meta-anfetamina durante la preñez, tiene consecuencias conductuales y neuroquímicas a largo plazo que se manifiestan en la edad adulta, como una alterada actividad locomotora, modificaciones en la síntesis y recambio de dopamina (DA) y cambios en el número de receptores dopaminérgicos en cuerpo estriado y el núcleo accumbens. El estrés es un factor crítico que lleva a estados patológicos como la depresión o la ansiedad y es dependiente del sexo. Existen similitudes en la respuesta al estrés y la acción de drogas psicoestimulantes tanto a nivel bioquímico como conductual. También existe un dimorfimo sexual en la respuesta a las drogas de abuso como los psicoestimulantes. Aunque hay evidencia que el tratamiento prenatal con anfetaminas regula la actividad del eje del estrés y la actividad dopaminérgica, la interacción de ambos no ha sido aún bien estudiada. En particular, no se ha profundizado el efecto de la exposición prenatal con anfetaminas y su impacto sobre las TIDA que ejercen un tono inhibitorio sobre la prolactina (PRL) hipofisaria. Las neuronas dopaminérgicas son reguladas por los péptidos opiodes endógenos que están ampliamente distribuidos en el SNC y participan en la regulación de muchas funciones como la respuesta al estrés, la acción de los psicoestimulantes y funciones endócrinas como el control de la secreción de PRL. Existe poca evidencia sobre los efectos de la exposición prenatal con psicoestimulantes en la modulación opioide de las neuronas TIDA y la respuesta hormonal al estrés en machos y hembras. En este proyecto estudiaremos la respuesta neuroquímica y neuroendocrina al estrés en ratas adultas machos y hembras, con exposición prenatal a D-anfetamina. Se evaluará a nivel del HMB la actividad dopaminérgica en el HMB en respuesta al estrés en animales machos y hembras determinando la expresión de la pTH, RD2 y DAT. Se evaluará la expresión de los receptores opioides y precursores opioides en HMB para estudiar el rol del sistema opioide en los cambios dopaminérgicos inducidos en respuesta al estrés en animales con exposición intra-útero con anfetaminas.Amphetamines are psychostimulants that act on monoaminergic systems with a mechanism of action similar to that of cocaine. Its consumption has increased in the country in pregnancy. Psychoactive drugs can easily cross the placental barrier and reach the fetus to affect normal brain development. Exposure to low doses of amphetamines or meta-amphetamine during pregnancy has long-term behavioral and neurochemical consequences that manifest themselves in adulthood, such as impaired locomotor activity, modifications in the synthesis and turnover of dopamine (DA), and changes in the number of dopaminergic receptors in the striatum and the nucleus accumbens. Stress is a critical factor that leads to pathological states such as depression or anxiety and is dependent on sex. There are similarities in the response to stress and the action of psychostimulant drugs at both the biochemical and behavioral levels. There is also a sexual dimorphism in the response to drugs of abuse such as psychostimulants. Although there is evidence that prenatal treatment with amphetamines regulates the activity of the stress axis and dopaminergic activity, the interaction of both has not yet been well studied. In particular, the effect of prenatal exposure with amphetamines and its impact on TIDA that exert an inhibitory tone on pituitary prolactin (PRL) has not been deepened. Dopaminergic neurons are regulated by endogenous opioid peptides that are widely distributed in the CNS and participate in the regulation of many functions such as the stress response, the action of psychostimulants and endocrine functions such as the control of PRL secretion. There is little evidence on the effects of prenatal exposure with psychostimulants on the opioid modulation of TIDA neurons and the hormonal response to stress in males and females. In this project we will study the neurochemical and neuroendocrine response to stress in adult male and female rats, with prenatal exposure to D-amphetamine. The dopaminergic activity in the HMB will be evaluated at HMB level in response to stress in male and female animals determining the expression of pTH, RD2 and DAT. The expression of opioid receptors and opioid precursors in HMB will be evaluated to study the role of the opioid system in the dopaminergic changes induced in response to stress in animals with intra-uterine exposure with amphetamines

Effect of hyperthyroidism on circulating prolactin and hypothalamic expression of tyrosine hydroxylase, prolactin signaling cascade members and estrogen and progesterone receptors during late pregnancy and lactation in the rat

Hyperthyroidism (HyperT) compromises pregnancy and lactation, hindering suckling-induced PRL release. We studied the effect of HyperT on hypothalamic mRNA (RT-qPCR) and protein (Western blot) expression of tyrosine hydroxylase (TH), PRL receptor (PRLR) and signaling pathway members, estrogen-α (ERα) and progesterone (PR) receptors on late pregnancy (days G19, 20 and 21) and early lactation (L2) in rats. HyperT advanced pre-partum PRL release, reduced circulating PRL on L2 and increased TH mRNA (G21 and L2), p-TH, PRLR mRNA, STAT5 protein (G19 and L2), PRLR protein (G21) and CIS protein (G19). PRs mRNAs and protein decreased on G19 but afterwards PRA mRNA (G20), PRB mRNA (G21) and PRA mRNA and protein (L2) increased. ERα protein increased on G19 and decreased on G20. Thus, the altered hypothalamic PRLR, STAT5, PR and ERα expression in hyperthyroid rats may induce elevated TH expression and activation, that consequently, elevate dopaminergic tone during lactation, blunting suckling-induced PRL release and litter growth.Fil: Pennacchio, Gisela Erika. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Neira, Flavia Judith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Soaje, Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; ArgentinaFil: Jahn, Graciela Alma. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Valdez, Susana Ruth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentin

Regulation by endogenous opioids of suckling-induced prolactin secretion in pregnant and lactating rats: Role of ovarian steroids

Evidence suggests that endogenous opioid peptides are implicated in the suckling-induced prolactin rise. We explored the role of the opioid system and the participation of ovarian hormones in the regulation of prolactin induced by the suckling stimulus at the end of pregnancy in rats with developed maternal behavior, and during lactation. Suckling for 24 h induced a significant increase in serum prolactin on day 19 of pregnancy, which was increased more than three times when naloxone (2 mg/kg s.c.) or mifepristone (2 mg/kg) was administered. The combination of naloxone and mifepristone did not increase serum prolactin more than either compound alone. Administration of tamoxifen (500 μg/kg orally) on days 14 and 15 of pregnancy completely abolished the effect of naloxone, indicating a role for estrogens in establishing this inhibitory role of opioids. To examine the participation of the opioid system during lactation, we used groups of rats on days 1, 3, 5, 12 and 19 postpartum either (i) isolated from the pups for 4 h, or (ii) isolated from the pups for 3.5 h and reunited with them and suckled for 30 min. Naloxone, given just before replacing the pups, prevented the increase in serum prolactin levels observed in the suckled group of rats but had no effect on the basal levels of the isolated rats. To examine whether the participation of the opioid system in the release of prolactin is dependent on the variation of progesterone levels, rats on day 20 of pregnancy were implanted with two cannulae containing progesterone (that blocked postpartum ovulation) or cholesterol, and cesarean surgery was performed on day 21. To maintain lactation, pups (1-3 days old) were replaced every 24 h, and 4 days after the cesarean eight pups were placed in the cage at 1800 h to maintain a strong suckling stimulus during the following 24 h. Naloxone administration significantly reduced serum prolactin levels in control (cholesterol) rats but progesterone implants prevented the inhibitory effect of naloxone and this effect was not modified by treatment with estrogen. These results indicate that the opioid system modulates suckling-induced prolactin secretion, passing from an inhibitory action before delivery to a stimulatory action during lactation. This regulatory shift seems to be dependent on the fall in progesterone concentration at the end of pregnancy and the subsequent increase after the postpartum ovulation and luteal phase.Fil: Soaje, Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: de Di Nasso, E. G.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Deis, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin

Effects of single injection of naloxone and damgo within nucleus accumbens septi in the plus maze test in rats

Nucleus accumbens septi (NAS) is studied because its relations with cognition and anxiety. Its pharmacological manipulation is widely used in experimental psychopathology to reproduce psychotic signs and symptoms in animal models. In the present study, the effect of the injection of an agonist and a µ-receptor antagonist in this structure is assessed. Holtzman strain male rats (240-290 g) were cannulated bilaterally in NAS. One week after the injection they were subjected to an anxiety test, prior saline injection (controls), DAMGO ([D-Ala2, N-MePhe4, Gly-ol]-encephalin, opioid agonist) or naloxone (opioid antagonist). We evaluated the set of parameters classically considered in our laboratory (open arm time, time per entry, open arm entries, closed arm entries, open/closed arm quotient, open and closed arm ends arrivals, rearing, fecal bowls and grooming behaviors. There was only a significant increase in the length of stay in the open arm with the injection of DAMGO (0.2 µg/1 µL, p < 0.05) and a significant increase in grooming behaviors with naloxone (1 µg/1 µL, p < 0.001), compared with saline controls (1 µL). We conclude that the receptor stimulation in NAS generates effects compatible with anxiolysis, and blocking of such receptor in said structure results in an increase in grooming behaviors.Fil: Morsucci C. Universidad Nacional de Cuyo; ArgentinaFil: Okasova A. Universidad Nacional de Cuyo; ArgentinaFil: Mulet, Daniela. Universidad Nacional de Cuyo; ArgentinaFil: Galiana, Graciana. Universidad Nacional de Cuyo; ArgentinaFil: Rodriguez, Vanesa. Universidad Nacional de Cuyo; ArgentinaFil: Baiardi, Gustavo Carlos. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; ArgentinaFil: Lafuente, José Vicente. Universidad Nacional de Cuyo; ArgentinaFil: Elias, Pablo Adolfo. Universidad Nacional de Cuyo; ArgentinaFil: Landa, Adriana. Universidad Nacional de Cuyo; ArgentinaFil: Soaje, Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Gargiulo, Pascual Angel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Long-term effects od neonatal hypoxia on anxiety-related behaviors and hormonal response to acute stress

Neonatal lesions in the brain have less severe effects than in adults due to the neuronal plasticity of the developing nervous system, although they can cause cognitive and behavioral sequelae. Previously, we found that neonatal hypoxia (NH) transiently affected the expression of proteins associated with synaptogenesis in certain brain areas. The intermingled neural circuits controlling both stress and anxiety suggest a strong relationship between stress experiences and anxiety in both healthy and pathological conditions. We evaluated the long-term effects of NH on anxiety parameters and in stress-induced hormone release in adult female (estrous day of rat cycle) and male rats. Sprague Dawley rats at 4 Post-Natal Day (PND) were exposed to an atmosphere of low oxygen level (6.5% O2 and 93.5% N2) for 70 min. 4PND control pups were exposed to normal oxygen levels (Co) for 70 min. The humidity and temperature conditions were controlled. Pups were then returned with their mother until weaned, and then they were allowed to grow. At 3 months of age, both groups of rats were subjected to two tests, Elevated Plus Maze (EPM) to measure anxiety parameters and a stressful challenge to determine hormone response to acute stress (exposure to ether vapors for 2 min). EPM reflected an unconditional aversion to heights and open spaces, an anxiogenic behavior. The hormonal response to stress included the release of pituitary prolactin (PRL), adrenal progesterone (P4), and adrenal corticosterone (CORT). Blood samples were collected before and after 5 min of stress exposure for serum hormone determinations by RIA. In the EPM test, both female and male hypoxic rats increased the number of entries to the open arms (OA) and the time spent in the OA compared to Co (P<0.05). The results obtained indicated an anxiolytic-related behavior induced by NH, that was higher in female than in male hypoxic rats. Basal levels (unstressed) of PRL and P4 in NH rats remained similar to Co ones in both sexes. Only in female rats, NH increased the basal levels of CORT compared Co rats (P<0.05). In female and male rats, the hormonal release of PRL, P4, and CORT induced by stress, were differentially affected by NH. Hypoxia attenuated the stress-induced PRL secretion in female rats (P<0.05) while this response was blocked in males. The release of CORT by stress was blunted in both sexes by NH. The release of P4 by stress was inhibited in NH female but it was preserved in male rats. In conclusion, the long-term effects of NH were influenced by sex. NH altered the anxiety levels and the hormonal response to stress in adulthood. The alterations caused by NH at the brain level could be influencing the appropriate response to situations of stress and anxiety in adulthood.Fil: Neira, Flavia Judith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Torrecilla, Norma Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Pennacchio, Gisela Erika. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Soaje, Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; ArgentinaFil: Jahn, Graciela Alma. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Seltzer, Alicia Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentina. Universidad Nacional de Villa Mercedes. Escuela de Cs. de la Salud; ArgentinaFil: Valdez, Susana Ruth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; ArgentinaXXXVII Reunión Científica Anual de la Sociedad de Biología de CuyoSan LuisArgentinaSociedad de Biología de Cuy

Differential effects of hypo- and hyperthyroidism on remodeling of contacts between neurons expressing the neuropeptide EI and tyrosine hydroxylase in hypothalamic areas of the male rat

The Neuropeptide EI (NEI, glutamic acid- isoleucine amide) participates in neuroendocrine function. Previously we demonstrated that NEI concentration is regulated by thyroid hormones in discrete hypothalamic areas in rats. We observed that the thyroid status affects the dopaminergic regulation of the pituitary hormones. In this study we explored possible interactions between NEI and tyrosine hydroxylase (TH) containing elements in selected hypothalamic areas of male rats. Neuronal somas, terminals and boutons were assessed by confocal microscopy, in hypo- and hyperthyroid animals. We observed a remodeling of the contacts between the TH and NEI immunoreactive elements in the incerto-hypothalamic area (IHy, also known as rostromedial zona incerta) according to thyroid function. However, in the dorsolateral zone of the peduncular part of the lateral hypothalamus (DL-PLH) the thyroid hormones affect the dendritic trees of the neurons without perturbing the overall NEI/TH contacts. Also, we demonstrated that TRH Receptor 1 (TRH-R1) is colocalized in NEI immunoreactive neurons in the peduncular part of the lateral hypothalamus (PLH) and NEI precursor mRNA expression increased by hypothyroidism indicating that NEI neurons are responsive to the feedback mechanisms of the Hypothalamic Pituitary-Thyroid Axis (HPT). In conclusion, the hypothyroid status seems to increase the interactions between the NEI neurons and the dopaminergic pathways while hyperthyroidism either decreases or displays no effects. Altogether these observations support the participation of the IHy and PLH NEI as a modulating component of the HPT suggesting that altered neuroendocrine, behavioral and cognitive dysfunctions induced by dysthyroidism could be in part mediated by NEI.Fil: Ayala, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Pennacchio, Gisela Erika. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Soaje, Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Bittencourt Guimaraes, Ana Tereza. Instituto de Ciencias Biomedicas; BrasilFil: Celis, Marìa E.. Universidad Nacional de Cordoba. Facultad de Medicina. Departamento de Medicina. Cat.de Bacteriologia y Virologia Medicas; ArgentinaFil: Jahn, Graciela Alma. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Valdez, Susana Ruth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Seltzer, Alicia Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentin

Hyperthyroidism enhances fetal and placental growth and placental immune cell infiltration

Thyroid dysfunctions cause reproductive disorders as fetal deaths, preterm birth and preeclampsia. Whether thyroid hormones (THs) exert any function in placental immune cells is unknown. Therefore, the aim of our work was to assess the influence of hyperthyroidism on placental immune cells as well as the impact on reproduction in pregnant rats. To this end, 10-12 weeks old Wistar rats were injected with a daily dose of T4 (0.1 or 0.25 mg/kg s.c) to induce hyperthyroidism (hyper) or vehicle in control animals. Rats were mated 8 days after starting T4 treatment and euthanized on day 19 (G19) and 20 (G20) of gestation. Placenta samples were minced to reach single cell suspension. Then, resident placental immune cells (CD45+) were analyzed by flow cytometry and mRNA content of hormone receptors by qPCR. Also, placental and fetus weights and fetus number were measured. Hyper mothers delivered more fetuses compared to controls (p<0.001). The offspring of hyper 0.25 mg/kg mothers weighed more in G19 and G20 (p<0.001). The placentas of the hyper 0.25 mg/kg mothers were heavier than controls only in G19 (p<0.001). Furthermore, we showed a decrease in the expression of progesterone, estrogen and ß2 thyroid receptors in hyper 0.1 mg/kg (p<0.05; p<0.01). On G19, the percentage of leukocytes was significantly higher in both hyper groups (p<0.05 for 0.1 mg/kg; p<0.01 for 0.25 mg/kg). On G20 we showed an increase in leukocyte infiltrate respect to G19 in the control (p<0.001) but not in the hyper group. These results suggest that T4 administration accelerates fetal development and changes the placental sensitivity to ovarian steroids by modulating their receptors expression and advances the increase in placental resident leukocytes. To our knowledge, this is the first report that shows the modulation of resident immune cells by thyroid hormones.Fil: Sánchez, María Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Moreno Sosa, María Tamara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Niera, Flavia Judith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Pietrobon, Elisa Olivia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Soaje, Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Valdez, Susana Ruth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Jahn, Graciela Alma. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Mackern Oberti, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaLXIV Reunión Anual de la Sociedad Argentina de Investigación Clínica; LI Reunión Anual de la Asociación Argentina de Farmacología Experimental; XXI Reunión Anual de la Sociedad Argentina de Biología; XXXI Reunión Anual de la Sociedad Argentina de Protozoología; IX Reunión Anual de la Asociación Argentina de Nanomedicinas; VI Reunión Científica Regional de la Asociación Argentina de Ciencia y Tecnología de Animales de LaboratorioMar del PlataArgentinaSociedad Argentina de Investigación ClínicaAsociación Argentina de Farmacología ExperimentalSociedad Argentina de BiologíaSociedad Argentina de ProtozoologíaAsociación Argentina de NanomedicinasAsociación Argentina de Ciencia y Tecnología de Animales de Laboratori

Hipertiroidismo incrementa el crecimiento fetal, el infiltrado leucocitario placentario y los niveles de corticosterona y prolactina en gestación tardía

Las disfunciones tiroideas pueden generar profundas alteraciones endócrinas y trastornos reproductivos durante la etapa gestacional. Sin embargo, se desconoce si el hipertiroidismo (H) puede modular la expresión de citoquinas e infiltrado celular leucocitario en placenta. Por lo antes mencionado, el objetivo del presente trabajo fue determinar la influencia del H en: i) los niveles séricos de hormonas inmunomoduladoras como prolactina y corticosterona, ii) infiltrado leucocitario, iii) la expresión de receptores hormonales iv) y citoquinas (IL-17, IL-8, VEGF, IL-1 β y TGF β). Para esto, fueron empleadas ratas Wistar hembras de 10-12 semanas de edad; las cuales fueron inyectadas diariamente con T4 (0.1 o 0.25 mg/kg s.c) con el objetivo de inducir H o con vehículo (grupo control)

VIII Encuentro de Docentes e Investigadores en Historia del Diseño, la Arquitectura y la Ciudad

Acta de congresoLa conmemoración de los cien años de la Reforma Universitaria de 1918 se presentó como una ocasión propicia para debatir el rol de la historia, la teoría y la crítica en la formación y en la práctica profesional de diseñadores, arquitectos y urbanistas. En ese marco el VIII Encuentro de Docentes e Investigadores en Historia del Diseño, la Arquitectura y la Ciudad constituyó un espacio de intercambio y reflexión cuya realización ha sido posible gracias a la colaboración entre Facultades de Arquitectura, Urbanismo y Diseño de la Universidad Nacional y la Facultad de Arquitectura de la Universidad Católica de Córdoba, contando además con la activa participación de mayoría de las Facultades, Centros e Institutos de Historia de la Arquitectura del país y la región. Orientado en su convocatoria tanto a docentes como a estudiantes de Arquitectura y Diseño Industrial de todos los niveles de la FAUD-UNC promovió el debate de ideas a partir de experiencias concretas en instancias tales como mesas temáticas de carácter interdisciplinario, que adoptaron la modalidad de presentación de ponencias, entre otras actividades. En el ámbito de VIII Encuentro, desarrollado en la sede Ciudad Universitaria de Córdoba, se desplegaron numerosas posiciones sobre la enseñanza, la investigación y la formación en historia, teoría y crítica del diseño, la arquitectura y la ciudad; sumándose el aporte realizado a través de sus respectivas conferencias de Ana Clarisa Agüero, Bibiana Cicutti, Fernando Aliata y Alberto Petrina. El conjunto de ponencias que se publican en este Repositorio de la UNC son el resultado de dos intensas jornadas de exposiciones, cuyos contenidos han posibilitado actualizar viejos dilemas y promover nuevos debates. El evento recibió el apoyo de las autoridades de la FAUD-UNC, en especial de la Secretaría de Investigación y de la Biblioteca de nuestra casa, como así también de la Facultad de Arquitectura de la UCC; va para todos ellos un especial agradecimiento

Role of Oxytocin in Prolactin Secretion during Late Pregnancy

Background/Aims: During late pregnancy, the blockade of progesterone action by mifepristone (Mp) treatment induces a dopaminergic tone fall that enables naloxone (NAL) administration to release pituitary prolactin (PRL). We determined whether oxytocin (OT), which stimulates PRL secretion acting directly on anterior pituitary lactotrophs, mediates the stimulatory action of Mp and NAL on PRL secretion during late pregnancy. Methods: On day 19 of pregnancy, circulating and pituitary OT and PRL levels were measured by radioimmunoassay, 10, 20, and 30 min after NAL (given at 17:30 h) in rats pretreated with Mp (at 08:00 h). Pituitary OT receptor (OTR) expression in Mp-treated rats was evaluated by RT-PCR. Activation of OT neurons in Mp-NAL-treated rats was measured counting double immunoreactive neurons for Fos and OT (Fos-OT-ir) in supraoptic nuclei (SON), and medial (PaMM) and lateral magnocellular divisions of paraventricular nuclei. Results: Elevated serum OT and decreased pituitary OT were observed 10 min after NAL administration in both vehicle-and Mp-treated rats. This PRL increase was prevented by previous i.p. administration of an OTR antagonist, but intracerebroventricular OT administration was ineffective. Mp increased pituitary OTR expression at 18:00 h. Only Mp-NAL increased Fos-OT-ir neurons in the PaMM and SON. Conclusions: These findings suggest that PRL secretion induced by Mp-NAL treatment is preceded by OT release. These results, together with the activation of hypothalamic OT neurons and the higher expression of pituitary OTR, support the hypothesis that, during late pregnancy, OT may act at the pituitary level to facilitate PRL secretion if the inhibitory action of progesterone is blocked.Fil: Villegas Gabutti, Carlos Mauricio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Pennacchio, Gisela Erika. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Vivas, Laura Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; ArgentinaFil: Jahn, Graciela Alma. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Soaje, Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin