Video didàctic per comprendre la cromatografia : utilització de la tècnica d'hplc per la determinació de canvis en la síntesi d'un neurotransmissor : la histamina

La finalitat principal del vídeo realitzat correspon a un dels objectius docents que proposàvem en el projecte que ens va ser concedit per l'AGAUR: que l'alumne es pugui acostar a tècniques sofisticades que per la seva complexitat o perillositat no poden realitzar-se en els laboratoris de docència. També com a segon objectiu, pretenem que l'alumne comprengui millor conceptes que s'expliquen a teoria. En la situació actual, els alumnes de primer curs de medicina realitzen pràctiques de laboratori en que apliquen la cromatografia en capa fina per la separació de molècules i l'anàlisi qualitatiu de la seva presència en mostres tissulars. Malgrat que els principis teòrics són bàsicament els mateixos, és impossible en la pràctica realitzar cromatografies d'alta resolució (HPLC) que són comunament utilitzades per la quantificació de molècules diverses, no només en la recerca bàsica sinó en el laboratori clínic. Per altra banda, els alumnes de tercer i quart curs de la llicenciatura de bioquímica coneixen les bases teòriques de l'HPLC però tampoc en els laboratoris de pràctiques pot realitzar-se cromatografies d'alta resolució degut al grau de complexitat i despesa que comporten

Agonist and antagonist effects of aripiprazole on D<inf>2</inf>-like receptors controlling rat brain dopamine synthesis depend on the dopaminergic tone

Supported by grants SAF2006-08240, SAF2009-12510, and Red de Trastornos Adictivos RD06/0001/0015. G.F.M. was the recipient of a CSC fellowship.Background: The atypical antipsychotic drug aripiprazole binds with high affinity to a number of G protein coupled receptors, including dopamine D2 receptors, where its degree of efficacy as a partial agonist remains controversial. Methods: We examined the properties of aripiprazole at D2-like autoreceptors by monitoring the changes of dopamine synthesis in adult rat brain striatal minces incubated ex vivo. The effects of the dopaminergic tone on the properties of aripiprazole were assayed by comparing a basal condition (2 mM K+, low dopaminergic tone) and a stimulated condition (15 mM K+ where dopamine release mimics a relatively higher dopaminergic tone). We also used 2 reference compounds: quinpirole showed a clear agonistic activity and preclamol (S-(-)-PPP) showed partial agonism under both basal and stimulated conditions. Results: Aripiprazole under the basal condition acted as an agonist at D2-like autoreceptors and fully activated them at about 10 nM, inhibiting dopamine synthesis similarly to quinpirole. Higher concentrations of aripiprazole had effects not restricted to D2-like autoreceptor activation. Under the stimulated (15 mM K+) condition, nanomolar concentrations of aripiprazole failed to decrease dopamine synthesis but could totally block the effect of quinpirole. Conclusions: Under high dopaminergic tone, aripiprazole acts as a D2-like autoreceptor antagonist rather than as an agonist. These data show that, ex vivo, alteration of dopaminergic tone by depolarization affects the actions of aripiprazole on D2-like autoreceptors. Such unusual effects were not seen with the typical partial agonist preclamol and are consistent with the hypothesis that aripiprazole is a functionally selective D2R ligand

Housing and road transport modify the brain neurotransmitter systems of pigs : Do pigs raised in different conditions cope differently with unknown environments?

How housing and transport conditions may affect welfare in porcine production is a leading topic in livestock research. This study investigated whether pigs present a different neurological response to management conditions and to ascertain whether pigs living partially outdoors cope differently with road transport-associated stress. Twenty-four female pigs were divided in two groups: one living indoors (ID, n = 12) and the other housed combining indoor conditions with 4 hours per day of outdoor pasture (OD, n = 12). After one month, one set of animals from each housing condition were driven in a truck to the slaughterhouse in low-stress conditions (5 min drive, no mixing groups, soft management, LS group, n = 12) or high-stress conditions (2 hours drive, mixing groups, harsh management, HS group, n = 12). At the slaughterhouse, blood was collected, and the prefrontal cortex (PFC) and the hippocampus (HC) dissected. OD pigs had lower serum haptoglobin and increased dopaminergic pathway (DA-system) in the PFC, suggesting that living outdoors increases their wellbeing. HS conditions increased serum creatine kinase (CK) and affected several brain pathways: activation of the noradrenergic (NA-system) and DA -system in the PFC and the activation of the DA-system and an increase in c-Fos as well as a decrease in brain-derived neurotrophic factor (BDNF) in the HC. The serotonergic system (5-HT-system) was mildly altered in both areas. There was an interaction between housing and transport in serum NA and the DA-system in the HC, indicating that living conditions affected the response to stress. Multivariate analysis was able to discriminate the four animal groups. In conclusion, this work indicates that housing conditions and road transport markedly modifies the neurophysiology of pigs, and suggests that animals raised partially outdoors respond differently to transport-associated stress than animals raised indoors, indicating that they cope differently with unknown environments

Effect of handling on neurotransmitter profile in pig brain according to fear related behaviour

Chemical neurotransmitters (NT) are principal actors in all neuronal networks of animals. The central nervous system plays an important role in stress susceptibility and organizes the response to a stressful situation through the interaction of the dopaminergic and the serotonergic pathways, leading to the activation of the hypothalamus-pituitary-adrenal axis (HPA). This study was designed to investigate: a) the effects of stressful handling of pigs at the slaughterhouse on the neurotransmitter profile in four brain areas: amygdala, prefrontal cortex (PFC), hippocampus and hypothalamus, and b) whether the alterations in the brain NT profile after stressful handling were associated with fear, determined by the tonic immobility (TI) test. In the first place, the characterization of the NT profile allowed to distinguish the four brain areas in a principal component analysis. The most crucial pathway involved in the reaction of pigs to a stressful handling was the serotonergic system, and changes were observed in the amygdala with a decrease in serotonin (5-HT) and total indoleamines, and in the hippocampus, where this pathway was activated. Fearful and non-fearful pigs did not show significant differences in their NT profile in control conditions, but when subjected to a stressful handling in the slaughterhouse, fearful animals showed a significant variation in the serotonin pathway and, in a lesser extent, the dopamine (DA) pathway. In conclusion, the existence of an underlying biological trait - possibly fearfulness - may be involved in the pig's response toward stressful challenges, and the serotonergic system seems to play a central role in this response

Cellular distribution of the histamine H3 receptor in the basal ganglia : functional modulation of dopamine and glutamate neurotransmission

This is the author's version of a work that was accepted for publication in Basal ganglia. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Vol. 3 Núm. 2 (Jul. 2013)Altres ajuts: Red_de_Trastornos_Adictivos/RD06/0001/0015Histamine H3 receptors (H3R) are widely expressed in the brain where they participate in sleep-wake cycle and cognition among other functions. Despite their high expression in some regions of the basal ganglia, their functional role in this forebrain neural network remains unclear. The present findings provide in situ hybridization and immunohistochemical evidence for H3R expression in several neuronal populations of the rat basal ganglia but not in astrocytes (glial fibrillary acidic protein immunoreactive cells). We demonstrate the presence of H3R mRNA and protein in dopaminergic neurons (tyrosine hydroxylase positive) of the ventral tegmental area and substantia nigra. In the dorsal and ventral (nucleus accumbens) striatal complex we show H3R immunoreactivity in cholinergic (choline acetyltransferase immunoreactive) and GABAergic neurons (substance P, proenkephalin or dopamine D1 receptor positive) as well as in corticostriatal terminals (VGLUT1-immunoreactive). Double-labelling experiments in the medial prefrontal cortex show that H3R is expressed in D1R-positive interneurons and VGLUT1-positive corticostriatal output neurons. Our functional experiments confirm that H3R ligands modulate dopamine synthesis and the probability of glutamate release in the striatum from cortico-striatal afferents. The presence of H3R in such different neuronal populations and its involvement in the control of striatal dopaminergic and glutamatergic transmission ascribes a complex role to H3R in the function of the basal ganglia neural network

Creació de vídeos de tècniques de bioquímica i de bases de dades de preguntes comentades

El treball dut a terme s'emmarca en un objectiu general de producció de materials perquè s'utilitzin com a eines per afavorir l'autoaprenentatge en un entorn de docència semipresencial. S'han fet dos vídeos de dues tècniques experimentals fonamentals en bioquímica: la cromatografia i la fixació de radiolligands. Ambdós vídeos corresponen a la filmació d'experiments que implicaven manipulacions sofisticades i es van dur a terme en els laboratoris docents de la Unitat de Bioquímica de Medicina. S'ha confeccionat una base de dades de preguntes de resposta múltiple que consta actualment de 200 preguntes de bioquímica i biologia molecular classificades i revisades. La utilització tutoritzada dels vídeos i de les preguntes, juntament amb l'avaluació de la comprensió de sessions presencials mitjançant un test ràpid i també l'apropament del coneixement bioquímic a coneixements intuïtius habituals, han permès millorar el rendiment acadèmic de l'alumnat, ja que se n'ha incrementat el nombre que superen les assignatures i també la proporció d'alumnat amb bones qualificacions.El trabajo llevado a cabo se enmarca en un objetivo general de producción de materiales para que se utilicen como herramientas para favorecer el autoaprendizaje en un entorno de docencia semipresencial. Se han hecho dos vídeos de dos técnicas experimentales fundamentales en bioquímica: la cromatografía y la fijación de radio-ligandos. Ambos vídeos corresponden a la filmación de experimentos que implicaban manipulaciones sofisticadas y se llevaron a cabo en los laboratorios docentes de la Unidad de Bioquímica de Medicina. Se ha confeccionado una base de datos de preguntas de respuesta múltiple que consta actualmente de 200 preguntas de bioquímica y biología molecular clasificadas y revisadas. La utilización tutorizada de los vídeos y de laspreguntas, junto con la evaluación de la comprensión de sesiones presenciales mediante un test rápido y también el acercamiento del conocimiento bioquímico a conocimientos intuitivos habituales, han permitido mejorar el rendimiento académico del alumnado, ya que se ha incrementado el número que superan las asignaturas y también la proporción de alumnado con buenas calificaciones.The general objective of this project is the production of materials for use as toolsfor promoting independent learning in a semi-distance learning environment. Two videos were produced of two basic experimental techniques in Biochemistry: chromatography and radioligand binding. Both videos include the filming of experiments that involved sophisticated manipulations which had to be carried out in the teaching laboratories of the Biochemistry Unit in the Faculty of Medicine. A data-base of multiple choice questions was produced. This currently consists of 200 classified and reviewed Biochemistry and Molecular Biology questions. Supervised use of the video and the questions, together with assessment of understanding of presence sessions by means of a Rapid Test and linking biochemical knowledge to normal intuitive knowledge, has led to an improvement in the academic performance of the students, as it has increased the number of students passing the subject as well as the proportion of students with good grades

Video didàctic per comprendre la cromatografia : utilització de la tècnica d'hplc per la determinació de canvis en la síntesi d'un neurotransmissor : la histamina

La finalitat principal del vídeo realitzat correspon a un dels objectius docents que proposàvem en el projecte que ens va ser concedit per l'AGAUR: que l'alumne es pugui acostar a tècniques sofisticades que per la seva complexitat o perillositat no poden realitzar-se en els laboratoris de docència. També com a segon objectiu, pretenem que l'alumne comprengui millor conceptes que s'expliquen a teoria. En la situació actual, els alumnes de primer curs de medicina realitzen pràctiques de laboratori en que apliquen la cromatografia en capa fina per la separació de molècules i l'anàlisi qualitatiu de la seva presència en mostres tissulars. Malgrat que els principis teòrics són bàsicament els mateixos, és impossible en la pràctica realitzar cromatografies d'alta resolució (HPLC) que són comunament utilitzades per la quantificació de molècules diverses, no només en la recerca bàsica sinó en el laboratori clínic. Per altra banda, els alumnes de tercer i quart curs de la llicenciatura de bioquímica coneixen les bases teòriques de l'HPLC però tampoc en els laboratoris de pràctiques pot realitzar-se cromatografies d'alta resolució degut al grau de complexitat i despesa que comporten

Agonist and antagonist effects of aripiprazole on D<inf>2</inf>-like receptors controlling rat brain dopamine synthesis depend on the dopaminergic tone

Background: The atypical antipsychotic drug aripiprazole binds with high affinity to a number of G protein coupled receptors, including dopamine D2 receptors, where its degree of efficacy as a partial agonist remains controversial. Methods: We examined the properties of aripiprazole at D2-like autoreceptors by monitoring the changes of dopamine synthesis in adult rat brain striatal minces incubated ex vivo. The effects of the dopaminergic tone on the properties of aripiprazole were assayed by comparing a basal condition (2 mM K+, low dopaminergic tone) and a stimulated condition (15 mM K+ where dopamine release mimics a relatively higher dopaminergic tone). We also used 2 reference compounds: quinpirole showed a clear agonistic activity and preclamol (S-(-)-PPP) showed partial agonism under both basal and stimulated conditions. Results: Aripiprazole under the basal condition acted as an agonist at D2-like autoreceptors and fully activated them at about 10 nM, inhibiting dopamine synthesis similarly to quinpirole. Higher concentrations of aripiprazole had effects not restricted to D2-like autoreceptor activation. Under the stimulated (15 mM K+) condition, nanomolar concentrations of aripiprazole failed to decrease dopamine synthesis but could totally block the effect of quinpirole. Conclusions: Under high dopaminergic tone, aripiprazole acts as a D2-like autoreceptor antagonist rather than as an agonist. These data show that, ex vivo, alteration of dopaminergic tone by depolarization affects the actions of aripiprazole on D2-like autoreceptors. Such unusual effects were not seen with the typical partial agonist preclamol and are consistent with the hypothesis that aripiprazole is a functionally selective D2R ligand

Housing and road transport modify the brain neurotransmitter systems of pigs : Do pigs raised in different conditions cope differently with unknown environments?

How housing and transport conditions may affect welfare in porcine production is a leading topic in livestock research. This study investigated whether pigs present a different neurological response to management conditions and to ascertain whether pigs living partially outdoors cope differently with road transport-associated stress. Twenty-four female pigs were divided in two groups: one living indoors (ID, n = 12) and the other housed combining indoor conditions with 4 hours per day of outdoor pasture (OD, n = 12). After one month, one set of animals from each housing condition were driven in a truck to the slaughterhouse in low-stress conditions (5 min drive, no mixing groups, soft management, LS group, n = 12) or high-stress conditions (2 hours drive, mixing groups, harsh management, HS group, n = 12). At the slaughterhouse, blood was collected, and the prefrontal cortex (PFC) and the hippocampus (HC) dissected. OD pigs had lower serum haptoglobin and increased dopaminergic pathway (DA-system) in the PFC, suggesting that living outdoors increases their wellbeing. HS conditions increased serum creatine kinase (CK) and affected several brain pathways: activation of the noradrenergic (NA-system) and DA -system in the PFC and the activation of the DA-system and an increase in c-Fos as well as a decrease in brain-derived neurotrophic factor (BDNF) in the HC. The serotonergic system (5-HT-system) was mildly altered in both areas. There was an interaction between housing and transport in serum NA and the DA-system in the HC, indicating that living conditions affected the response to stress. Multivariate analysis was able to discriminate the four animal groups. In conclusion, this work indicates that housing conditions and road transport markedly modifies the neurophysiology of pigs, and suggests that animals raised partially outdoors respond differently to transport-associated stress than animals raised indoors, indicating that they cope differently with unknown environments

Benvinguda als nous alumnes de la Facultat de Medicina

Presentació de la Facultat de Medicina als nous alumnes de 1er curs 2014/2015 dels Graus de Medicina, Infermeria i Fisioteràpia