RESUMEN
Assisted reproductive technologies (ARTs), including in vitro maturation and fertilization (IVF), are increasingly used in human and animal reproduction. Whether these technologies directly affect the rate of de novo mutation (DNM), and to what extent, has been a matter of debate. Here we take advantage of domestic cattle, characterized by complex pedigrees that are ideally suited to detect DNMs and by the systematic use of ART, to study the rate of de novo structural variation (dnSV) in this species and how it is impacted by IVF. By exploiting features of associated de novo point mutations (dnPMs) and dnSVs in clustered DNMs, we provide strong evidence that (1) IVF increases the rate of dnSV approximately fivefold, and (2) the corresponding mutations occur during the very early stages of embryonic development (one- and two-cell stage), yet primarily affect the paternal genome.
Asunto(s)
Desarrollo Embrionario , Familia , Embarazo , Femenino , Animales , Bovinos , Humanos , Mutación , Linaje , Genoma HumanoRESUMEN
BACKGROUND: Structural variants (SVs) are chromosomal segments that differ between genomes, such as deletions, duplications, insertions, inversions and translocations. The genomics revolution enabled the discovery of sub-microscopic SVs via array and whole-genome sequencing (WGS) data, paving the way to unravel the functional impact of SVs. Recent human expression QTL mapping studies demonstrated that SVs play a disproportionally large role in altering gene expression, underlining the importance of including SVs in genetic analyses. Therefore, this study aimed to generate and explore a high-quality bovine SV catalogue exploiting a unique cattle family cohort data (total 266 samples, forming 127 trios). RESULTS: We curated 13,731 SVs segregating in the population, consisting of 12,201 deletions, 1,509 duplications, and 21 multi-allelic CNVs (> 50-bp). Of these, we validated a subset of copy number variants (CNVs) utilising a direct genotyping approach in an independent cohort, indicating that at least 62% of the CNVs are true variants, segregating in the population. Among gene-disrupting SVs, we prioritised two likely high impact duplications, encompassing ORM1 and POPDC3 genes, respectively. Liver expression QTL mapping results revealed that these duplications are likely causing altered gene expression, confirming the functional importance of SVs. Although most of the accurately genotyped CNVs are tagged by single nucleotide polymorphisms (SNPs) ascertained in WGS data, most CNVs were not captured by individual SNPs obtained from a 50K genotyping array. CONCLUSION: We generated a high-quality SV catalogue exploiting unique whole genome sequenced bovine family cohort data. Two high impact duplications upregulating the ORM1 and POPDC3 are putative candidates for postpartum feed intake and hoof health traits, thus warranting further investigation. Generally, CNVs were in low LD with SNPs on the 50K array. Hence, it remains crucial to incorporate CNVs via means other than tagging SNPs, such as investigation of tagging haplotypes, direct imputation of CNVs, or direct genotyping as done in the current study. The SV catalogue and the custom genotyping array generated in the current study will serve as valuable resources accelerating utilisation of full spectrum of genetic variants in bovine genomes.
Asunto(s)
Genoma , Genómica , Femenino , Humanos , Bovinos , Animales , Genómica/métodos , Genotipo , Variaciones en el Número de Copia de ADN , Haplotipos , Polimorfismo de Nucleótido Simple , Proteínas Musculares/genética , Moléculas de Adhesión Celular/genéticaRESUMEN
The purpose of this study was to gather opinions from experts via the Delphi method to inform the future development of a virtual reality based English language communication program for university level students in Korea. The participants, who consisted of a panel of experts and professors who majored in English language and multimedia education, completed three Delphi surveys based on Context, Input, Process, and Product evaluation, which is referred to as CIPP. In the first Delphi survey, the participants answered multiple choice questions and open-ended questions related to four areas relevant to the development of a virtual reality based program. Based on their answers, a second Delphi survey was designed to determine the participants' level of agreement with the appropriateness of the questions related to the four areas. In the third Delphi survey, participants were shown the results (mean, standard deviation, median, interquartile range, consensus chart, and convergence degree) and were asked to confirm or modify their answers based on the other participants' answers. According to the analysis of the Delphi survey results, need for the development of a virtual reality based English language communication program was suggested, and recommendations were made regarding the content and application of the program.
Asunto(s)
Lenguaje , Realidad Virtual , Comunicación , Consenso , Técnica Delphi , Humanos , Encuestas y CuestionariosRESUMEN
Clinical mastitis (CM) is an inflammatory disease occurring in the mammary glands of lactating cows. CM is under genetic control, and a prominent CM resistance QTL located on chromosome 6 was reported in various dairy cattle breeds. Nevertheless, the biological mechanism underpinning this QTL has been lacking. Herein, we mapped, fine-mapped, and discovered the putative causal variant underlying this CM resistance QTL in the Dutch dairy cattle population. We identified a ~12 kb multi-allelic copy number variant (CNV), that is in perfect linkage disequilibrium with a lead SNP, as a promising candidate variant. By implementing a fine-mapping and through expression QTL mapping, we showed that the group-specific component gene (GC), a gene encoding a vitamin D binding protein, is an excellent candidate causal gene for the QTL. The multiplicated alleles are associated with increased GC expression and low CM resistance. Ample evidence from functional genomics data supports the presence of an enhancer within this CNV, which would exert cis-regulatory effect on GC. We observed that strong positive selection swept the region near the CNV, and haplotypes associated with the multiplicated allele were strongly selected for. Moreover, the multiplicated allele showed pleiotropic effects for increased milk yield and reduced fertility, hinting that a shared underlying biology for these effects may revolve around the vitamin D pathway. These findings together suggest a putative causal variant of a CM resistance QTL, where a cis-regulatory element located within a CNV can alter gene expression and affect multiple economically important traits.
Asunto(s)
Elementos de Facilitación Genéticos , Mastitis Bovina/genética , Proteína de Unión a Vitamina D/genética , Animales , Bovinos , Variaciones en el Número de Copia de ADN , Femenino , Predisposición Genética a la Enfermedad , Haplotipos , Desequilibrio de Ligamiento , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Secuenciación Completa del GenomaRESUMEN
BACKGROUND: Copy Number Variations (CNVs) are gain or loss of DNA segments that are known to play a role in shaping a wide range of phenotypes. In this study, we used two dairy cattle populations, Holstein Friesian and Jersey, to discover CNVs using the Illumina BovineHD Genotyping BeadChip aligned to the ARS-UCD1.2 assembly. The discovered CNVs were investigated for their functional impact and their population genetics features. RESULTS: We discovered 14,272 autosomal CNVs, which were aggregated into 1755 CNV regions (CNVR) from 451 animals. These CNVRs together cover 2.8% of the bovine autosomes. The assessment of the functional impact of CNVRs showed that rare CNVRs (MAF < 0.01) are more likely to overlap with genes, than common CNVRs (MAF ≥ 0.05). The Population differentiation index (Fst) based on CNVRs revealed multiple highly diverged CNVRs between the two breeds. Some of these CNVRs overlapped with candidate genes such as MGAM and ADAMTS17 genes, which are related to starch digestion and body size, respectively. Lastly, linkage disequilibrium (LD) between CNVRs and BovineHD BeadChip SNPs was generally low, close to 0, although common deletions (MAF ≥ 0.05) showed slightly higher LD (r2 = ~ 0.1 at 10 kb distance) than the rest. Nevertheless, this LD is still lower than SNP-SNP LD (r2 = ~ 0.5 at 10 kb distance). CONCLUSIONS: Our analyses showed that CNVRs detected using BovineHD BeadChip arrays are likely to be functional. This finding indicates that CNVs can potentially disrupt the function of genes and thus might alter phenotypes. Also, the population differentiation index revealed two candidate genes, MGAM and ADAMTS17, which hint at adaptive evolution between the two populations. Lastly, low CNVR-SNP LD implies that genetic variation from CNVs might not be fully captured in routine animal genetic evaluation, which relies solely on SNP markers.
Asunto(s)
Variaciones en el Número de Copia de ADN , Genética de Población , Animales , Cruzamiento , Bovinos , Genoma , Desequilibrio de Ligamiento , Sitios de Carácter CuantitativoRESUMEN
Wild boar (Sus scrofa) drastically colonized mainland Eurasia and North Africa, most likely from East Asia during the Plio-Pleistocene (2-1Mya). In recent studies, based on genome-wide information, it was hypothesized that wild boar did not replace the species it encountered, but instead exchanged genetic materials with them through admixture. The highly endangered pygmy hog (Porcula salvania) is the only suid species in mainland Eurasia known to have outlived this expansion, and therefore provides a unique opportunity to test this hybridization hypothesis. Analyses of pygmy hog genomes indicate that despite large phylogenetic divergence (~2 My), wild boar and pygmy hog did indeed interbreed as the former expanded across Eurasia. In addition, we also assess the taxonomic placement of the donor of another introgression, pertaining to a now-extinct species with a deep phylogenetic placement in the Suidae tree. Altogether, our analyses indicate that the rapid spread of wild boar was facilitated by inter-specific/inter-generic admixtures.
Asunto(s)
Genómica/métodos , Sus scrofa/clasificación , Sus scrofa/genética , África del Norte , Animales , ADN Mitocondrial/genética , Filogenia , Análisis de Secuencia de ADN , PorcinosRESUMEN
Most previous studies of 3D shape perception have shown a general inability to visually perceive metric shape. In line with this, studies of object recognition have shown that only qualitative differences, not quantitative or metric ones can be used effectively for object recognition. Recently, Bingham and Lind (2008) found that large perspective changes (≥ 45°) allow perception of metric shape and Lee and Bingham (2010) found that this, in turn, allowed accurate feedforward reaches-to-grasp objects varying in metric shape. We now investigated whether this information would allow accurate and effective recognition of objects that vary in respect to metric shape. Both judgment accuracies (d') and reaction times confirmed that, with the availability of visual information in large perspective changes, recognition of objects using quantitative as compared to qualitative properties was equivalent in accuracy and speed of judgments. The ability to recognize objects based on their metric shape is, therefore, a function of the availability or unavailability of requisite visual information. These issues and results are discussed in the context of the Two Visual System hypothesis of Milner and Goodale (1995, 2006).
Asunto(s)
Percepción de Forma/fisiología , Reconocimiento en Psicología/fisiología , Adolescente , Adulto , Análisis de Varianza , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estimulación Luminosa , Adulto JovenRESUMEN
During wakefulness and in absence of performing tasks or sensory processing, the default-mode network (DMN), an intrinsic central nervous system (CNS) network, is in an active state. Non-human primate and human CNS imaging studies have identified the DMN in these two species. Clinical imaging studies have shown that the pattern of activity within the DMN is often modulated in various disease states (e.g., Alzheimer's, schizophrenia or chronic pain). However, whether the DMN exists in awake rodents has not been characterized. The current data provides evidence that awake rodents also possess 'DMN-like' functional connectivity, but only subsequent to habituation to what is initially a novel magnetic resonance imaging (MRI) environment as well as physical restraint. Specifically, the habituation process spanned across four separate scanning sessions (Day 2, 4, 6 and 8). At Day 8, significant (p<0.05) functional connectivity was observed amongst structures such as the anterior cingulate (seed region), retrosplenial, parietal, and hippocampal cortices. Prior to habituation (Day 2), functional connectivity was only detected (p<0.05) amongst CNS structures known to mediate anxiety (i.e., anterior cingulate (seed region), posterior hypothalamic area, amygdala and parabracial nucleus). In relating functional connectivity between cingulate-default-mode and cingulate-anxiety structures across Days 2-8, a significant inverse relationship (râ=â-0.65, pâ=â0.0004) was observed between these two functional interactions such that increased cingulate-DMN connectivity corresponded to decreased cingulate anxiety network connectivity. This investigation demonstrates that the cingulate is an important component of both the rodent DMN-like and anxiety networks.
Asunto(s)
Encéfalo/fisiología , Red Nerviosa/fisiología , Vigilia/fisiología , Animales , Ansiedad/fisiopatología , Encéfalo/anatomía & histología , Mapeo Encefálico , Giro del Cíngulo/anatomía & histología , Giro del Cíngulo/fisiología , Hipotálamo/anatomía & histología , Hipotálamo/fisiología , Imagen por Resonancia Magnética/métodos , Masculino , Modelos Neurológicos , Red Nerviosa/anatomía & histología , Lóbulo Parietal/anatomía & histología , Lóbulo Parietal/fisiología , Corteza Prefrontal/anatomía & histología , Corteza Prefrontal/fisiología , Ratas , Ratas Long-Evans , Frecuencia Respiratoria/fisiologíaRESUMEN
BACKGROUND: Intra-articular injection of monosodium iodoacetate (MIA) in the knee joint of rats disrupts chondrocyte metabolism resulting in cartilage degeneration and subsequent nociceptive behavior that has been described as a model of osteoarthritis (OA) pain. Central sensitization through activation of mitogen activated protein kinases (MAPKs) is recognized as a pathogenic mechanism in chronic pain. In the present studies, induction of central sensitization as indicated by spinal dorsal horn MAPK activation, specifically ERK and p38 phosphorylation, was assessed in the MIA-OA model. RESULTS: Behaviorally, MIA-injected rats displayed reduced hind limb grip force 1, 2, and 3 weeks post-MIA treatment. In the same animals, activation of phospho ERK1/2 was gradually increased, reaching a significant level at post injection week 3. Conversely, phosphorylation of p38 MAPK was enhanced maximally at post injection week 1 and decreased, but remained elevated, thereafter. Double labeling from 3-wk MIA rats demonstrated spinal pERK1/2 expression in neurons, but not glia. In contrast, p-p38 was expressed by microglia and a subpopulation of neurons, but not astrocytes. Additionally, there was increased ipsilateral expression of microglia, but not astrocytes, in 3-wk MIA-OA rats. Consistent with increased MAPK immunoreactivity in the contralateral dorsal horn, mechanical allodynia to the contralateral hind-limb was observed 3-wk following MIA. Finally, intrathecal injection of the MEK1 inhibitor PD98059 blocked both reduced hind-limb grip force and pERK1/2 induction in MIA-OA rats. CONCLUSION: Results of these studies support the role of MAPK activation in the progression and maintenance of central sensitization in the MIA-OA experimental pain model.
Asunto(s)
Articulaciones/patología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Dolor/enzimología , Dolor/patología , Médula Espinal/enzimología , Médula Espinal/patología , Animales , Conducta Animal/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Flavonoides/farmacología , Hiperalgesia/complicaciones , Hiperalgesia/patología , Inmunohistoquímica , Inyecciones Intraarticulares , Yodoacetatos/administración & dosificación , Articulaciones/efectos de los fármacos , MAP Quinasa Quinasa 1/antagonistas & inhibidores , MAP Quinasa Quinasa 1/metabolismo , Neuroglía/enzimología , Neuroglía/patología , Nociceptores/efectos de los fármacos , Nociceptores/metabolismo , Nociceptores/patología , Osteoartritis/complicaciones , Osteoartritis/enzimología , Osteoartritis/patología , Dolor/inducido químicamente , Dolor/complicaciones , Fenotipo , Fosforilación/efectos de los fármacos , Células del Asta Posterior/efectos de los fármacos , Células del Asta Posterior/enzimología , Células del Asta Posterior/patología , Ratas , Médula Espinal/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
The design, synthesis, and structure-activity relationships of a novel series of pyrazines, acting as corticotropin releasing factor-1 (CRF-1) receptor antagonists, are described. Synthetic methodologies were developed to prepare a number of substituted pyrazine cores utilizing regioselective halogenation and chemoselective derivatization. Noteworthy, an efficient 5-step synthesis was developed for the lead compound 59 (NGD 98-2), which required no chromatography. Compound 59 was characterized as an orally bioavailable, brain penetrant, and highly selective CRF-1 receptor antagonist. Occupancy of rat brain CRF-1 receptors was quantified using ex vivo receptor occupancy assays, using both brain tissue homogenates as well as brain slices receptor autoradiography. Behaviorally, oral administration of 59 significantly antagonized CRF-induced locomotor activity at doses as low as 10 mg/kg and dose-dependently reduced the restraint stress-induced ACTH increases.
Asunto(s)
Pirazinas/síntesis química , Receptores de Hormona Liberadora de Corticotropina/antagonistas & inhibidores , Tejido Adiposo/metabolismo , Administración Oral , Hormona Adrenocorticotrópica/sangre , Animales , Disponibilidad Biológica , Barrera Hematoencefálica/metabolismo , Línea Celular , Corteza Cerebral/metabolismo , Humanos , Técnicas In Vitro , Inyecciones Intraventriculares , Masculino , Microsomas Hepáticos/metabolismo , Actividad Motora/efectos de los fármacos , Pirazinas/química , Pirazinas/farmacología , Ensayo de Unión Radioligante , Ratas , Receptores de Hormona Liberadora de Corticotropina/metabolismo , Restricción Física , Relación Estructura-ActividadRESUMEN
Lee et al. (Percept Psychophys 70:1032-1046, 2008a) investigated whether visual perception of metric shape could be calibrated when used to guide feedforward reaches-to-grasp. It could not. Seated participants viewed target objects (elliptical cylinders) in normal lighting using stereo vision and free head movements that allowed small (approximately 10 degrees) perspective changes. The authors concluded that poor perception of metric shape was the reason reaches-to-grasp should be visually guided online. However, Bingham and Lind (Percept Psychophys 70:524-540, 2008) showed that large perspective changes (> or =45 degrees) yield good perception of metric shape. So, now we repeated the Lee et al.'s study with the addition of information from large perspective changes. The results were accurate feedforward reaches-to-grasp reflecting accurate perception of both metric shape and metric size. Large perspective changes occur when one locomotes into a workspace in which reaches-to-grasp are subsequently performed. Does the resulting perception of metric shape persist after the large perspective changes have ceased? Experiments 2 and 3 tested reaches-to-grasp with delays (Exp. 2, 5-s delay; Exp. 3, approximately 16-s delay) and multiple objects to be grasped after a single viewing. Perception of metric shape and metric size persisted yielding accurate reaches-to-grasp. We advocate the study of nested actions using a dynamic approach to perception/action.
Asunto(s)
Percepción de Forma/fisiología , Fuerza de la Mano , Percepción del Tamaño/fisiología , Percepción Visual/fisiología , Adolescente , Adulto , Femenino , Humanos , Juicio , Masculino , Adulto JovenRESUMEN
Dopamine D2 receptor blockade has been an obligate mechanism of action present in all medications that effectively treat positive symptoms of schizophrenia (e.g., delusions and hallucinations) and have been approved by regulatory agencies since the 1950s. Blockade of 5-hydroxytryptamine(2A) receptors plays a contributory role in the actions of the second generation of antipsychotic drugs, the so-called atypical antipsychotics. Nevertheless, substantial unmet medical needs remain for the treatment of negative symptoms and cognitive dysfunction. Recognition that dissociative anesthetics block the N-methyl-D-aspartate (NMDA) receptor channel has inspired a search for glutamatergic therapeutic mechanisms because ketamine and phencyclidine are known to induce psychotic-like symptoms in healthy volunteers and exacerbate the symptoms of patients with schizophrenia. Current pathophysiological theories of schizophrenia emphasize that hypofunction of NMDA receptors at critical sites in local circuits modulate the function of a given brain region or control projections from one region to another (e.g., hippocampal-cortical or thalamocortical projections). The demonstration that a metabotropic glutamate 2/3 (mGlu2/3) receptor agonist prodrug decreased both positive and negative symptoms of schizophrenia raised hopes that glutamatergic mechanisms may provide therapeutic advantages. In addition to discussing the activation of mGlu2 receptors with mGlu2/3 receptor agonists or mGlu2 receptor positive allosteric modulators (PAMs), we discuss other methods that may potentially modulate circuits with hypofunctional NMDA receptors such as glycine transporter inhibitors and mGlu5 receptor PAMs. The hope is that by modulating glutamatergic neurotransmission, the dysfunctional circuitry of the schizophrenic brain (both local circuits and long-loop pathways) will be improved.
Asunto(s)
Lóbulo Frontal/fisiología , Red Nerviosa/fisiología , Receptores de N-Metil-D-Aspartato/fisiología , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatología , Animales , Lóbulo Frontal/efectos de los fármacos , Humanos , Interneuronas/metabolismo , Interneuronas/patología , Red Nerviosa/efectos de los fármacos , Receptores AMPA/agonistas , Receptores AMPA/antagonistas & inhibidores , Receptores AMPA/fisiología , Receptores de N-Metil-D-Aspartato/agonistas , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Esquizofrenia/tratamiento farmacológico , Potenciales Sinápticos/fisiologíaRESUMEN
In a natural environment, cast shadows abound. Objects cast shadows both upon themselves and upon background surfaces. Previous research on the perception of 3-D shape from cast shadows has only examined the informativeness of shadows cast upon flat background surfaces. In outdoor environments, however, background surfaces often possess significant curvature (large rocks, trees, hills, etc.), and this background curvature distorts the shape of cast shadows. The purpose of this study was to determine the extent to which observers can "discount" the distorting effects of curved background surfaces. In our experiments, observers viewed deforming or static shadows of naturally shaped objects, which were cast upon flat and curved background surfaces. The results showed that the discrimination of 3-D object shape from cast shadows was generally invariant over the distortions produced by hemispherical background surfaces. The observers often had difficulty, however, in identifying the shadows cast onto saddle-shaped background surfaces. The variations in curvature which occur in different directions on saddle-shaped background surfaces cause shadow distortions that lead to difficulties in object recognition and discrimination.
Asunto(s)
Discriminación en Psicología/fisiología , Percepción de Forma/fisiología , Estimulación Luminosa/métodos , Reconocimiento en Psicología/fisiología , Análisis de Varianza , Señales (Psicología) , HumanosRESUMEN
Both judgment studies and studies of feedforward reaching have shown that the visual perception of object distance, size, and shape are inaccurate. However, feedback has been shown to calibrate feedfoward reaches-to-grasp to make them accurate with respect to object distance and size. We now investigate whether shape perception (in particular, the aspect ratio of object depth to width) can be calibrated in the context of reaches-to-grasp. We used cylindrical objects with elliptical cross-sections of varying eccentricity. Our participants reached to grasp the width or the depth of these objects with the index finger and thumb. The maximum grasp aperture and the terminal grasp aperture were used to evaluate perception. Both occur before the hand has contacted an object. In Experiments 1 and 2, we investigated whether perceived shape is recalibrated by distorted haptic feedback. Although somewhat equivocal, the results suggest that it is not. In Experiment 3, we tested the accuracy of feedforward grasping with respect to shape with haptic feedback to allow calibration. Grasping was inaccurate in ways comparable to findings in shape perception judgment studies. In Experiment 4, we hypothesized that online guidance is needed for accurate grasping. Participants reached to grasp either with or without vision of the hand. The result was that the former was accurate, whereas the latter was not. We conclude that shape perception is not calibrated by feedback from reaches-to-grasp and that online visual guidance is required for accurate grasping because shape perception is poor.
Asunto(s)
Percepción de Forma , Fuerza de la Mano , Internet , Percepción Visual , Adulto , Humanos , JuicioRESUMEN
Increased extra-hypothalamic corticotrophin-releasing factor (CRF) neurotransmission has been suggested as one putative factor in the pathophysiology of anxiety disorders. We have previously reported that administering repeated subanxiogenic doses (termed 'priming') of the CRF receptor agonist urocortin 1 (Ucn1) into the basolateral amygdala (BLA) of rats elicited long-lasting behavioral changes in social interaction (SI) and elevated plus maze (EPM) tests of anxiety. Although substantial similarity exists, the bed nucleus of the stria terminals (BNST) and the amygdala are thought to play distinct roles in anxiety responses. Rats primed with Ucn1 in the BLA not only demonstrated increased anxiety-like behaviors, but also physiological sensitivity to intravenous sodium lactate infusions, which is seen in subjects with panic or posttraumatic stress disorders, but not social or generalized anxiety disorders. In the present study, we tested if similar priming with subanxiogenic doses of Ucn1 in the BNST of rats will induce either chronic anxiety or sensitivity to sodium lactate. After determining the dose of Ucn1 that is subanxiogenic when injected into the BNST, repeated intra-BNST injections of this subanxiogenic dose of Ucn1 (6 fmol/100 nl) elicited persistent (present even after 4 weeks) anxiety-like responses in the SI but not EPM test. Prior local injection of a CRF receptor antagonist, astressin, into the BNST blocked this effect. Unlike Ucn1 priming in the BLA, rats primed in the BNST showed no cardiovascular changes following lactate infusion. Thus, BNST priming appears to selectively model the pathophysiology of subjects with anxiety syndromes like social anxiety, which are not lactate sensitive.
Asunto(s)
Ansiedad/metabolismo , Ansiedad/fisiopatología , Pánico/fisiología , Receptores de Hormona Liberadora de Corticotropina/fisiología , Núcleos Septales/fisiología , Conducta Social , Animales , Ansiedad/inducido químicamente , Hormona Liberadora de Corticotropina/administración & dosificación , Masculino , Pánico/efectos de los fármacos , Fragmentos de Péptidos/administración & dosificación , Ratas , Ratas Wistar , Receptores de Hormona Liberadora de Corticotropina/agonistas , Receptores de Hormona Liberadora de Corticotropina/antagonistas & inhibidores , Núcleos Septales/efectos de los fármacos , Urocortinas/administración & dosificaciónRESUMEN
INTRODUCTION: Recent evidence in clinical and preclinical studies has implicated glutamate neurotransmissions in pathophysiology of mood disorders. The regulation of amino acid neurotransmission, i.e., glutamate and gamma-aminobutyric acid (GABA) involves coordinated mechanisms of uptake and transport within a tripartite synaptic system that includes neurons and glia. Newly appreciated role of the glia, more specifically astrocytes on neuronal functions combined with reported postmortem abnormalities of glia in patients with mood disorders further supports the role of glia in mood disorders. MATERIALS AND METHODS: This report presents some of our preliminary results utilizing glia-selective toxins and other pharmacological tools to suppress glial function within the limbic system to study the resulting behavioral abnormalities, and thus, elucidate glial involvement in the development of mood disorders. RESULTS AND DISCUSSION: We demonstrate that chronic blockade of glutamate uptake by a glial/neuronal transporter antagonist L-trans-pyrrolidine-2,4-dicarboxylic acid (PDC) within the amygdala, a key area implicated in mood regulation, results in dose-dependent reduction in social exploratory behavior and disrupts circadian activity patterns consistent with symptoms of mood disorders. Similarly, the selective astrocytic glutamate transporter type 1 (GLT-1) blocker dihydrokainic acid (DHK) injected into the amygdala also results in reduced social interaction that is blocked by selective glutamate N-methyl-D-aspartate (NMDA) type receptor antagonist AP5. The results are discussed in the context of glial and glutamate mechanisms in mood disorders and potential therapeutic avenues to address these mechanisms.
Asunto(s)
Afecto , Amígdala del Cerebelo/metabolismo , Astrocitos/metabolismo , Conducta Animal , Transportador 2 de Aminoácidos Excitadores/metabolismo , Ácido Glutámico/metabolismo , Afecto/efectos de los fármacos , Sistema de Transporte de Aminoácidos X-AG/metabolismo , Amígdala del Cerebelo/citología , Amígdala del Cerebelo/efectos de los fármacos , Animales , Astrocitos/efectos de los fármacos , Conducta Animal/efectos de los fármacos , Ritmo Circadiano/efectos de los fármacos , Ácidos Dicarboxílicos/farmacología , Relación Dosis-Respuesta a Droga , Transportador 2 de Aminoácidos Excitadores/antagonistas & inhibidores , Conducta Exploratoria/efectos de los fármacos , Ácido Kaínico/análogos & derivados , Ácido Kaínico/farmacología , Masculino , Trastornos del Humor/metabolismo , Neuroglía/metabolismo , Inhibidores de la Captación de Neurotransmisores/farmacología , Pirrolidinas/farmacología , Ratas , Ratas Wistar , Receptores de N-Metil-D-Aspartato/metabolismo , Conducta SocialRESUMEN
Both a 5-hydroxytryptamine2A (5-HT2A) agonist and immobilization stress previously have been shown to differentially alter brain-derived neurotrophic factor (BDNF) mRNA expression in the neocortex and hippocampus. Both 5-HT2A receptor activation and immobilization stress also increase glutamate release in the rat prefrontal cortex. Given that the metabotropic glutamate2/3 receptor (mGluR2/3) agonist (1S,2S,5R,6S)-2-aminobicyclo[3.1.0] hexane-2,6-dicarboxylate monohydrate (LY354740) suppressed electrophysiological, behavioral and biochemical effects of 5-HT2A receptor activation in the medial prefrontal cortex (mPFC), we assessed the efficacy of the mGluR2/3 agonist in suppressing the stress-induced increase in BDNF mRNA expression. LY35740 (10 mg/kg, i.p.) attenuated the immobilization stress-induced increase in BDNF mRNA expression in the rat mPFC. This result is consistent with the hypothesis that mGlu2/3 agonists may be an efficacious treatment for stress-induced neuropsychiatric syndromes.
Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/biosíntesis , Compuestos Bicíclicos con Puentes/farmacología , Corteza Prefrontal/efectos de los fármacos , ARN Mensajero/biosíntesis , Receptores de Glutamato Metabotrópico/agonistas , Estrés Psicológico/metabolismo , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Inmovilización , Masculino , Corteza Prefrontal/metabolismo , Ratas , Ratas Sprague-DawleyRESUMEN
The ability of observers to perceive three-dimensional (3-D) distances or lengths along intrinsically curved surfaces was investigated in three experiments. Three physically curved surfaces were used: convex and/or concave hemispheres (Experiments 1 and 3) and a hyperbolic paraboloid (Experiment 2). The first two experiments employed a visual length-matching task, but in the final experiment the observers estimated the surface lengths motorically by varying the separation between their two index fingers. In general, the observers' judgments of surface length in both tasks (perceptual vs. motoric matching) were very precise but were not necessarily accurate. Large individual differences (overestimation, underestimation, etc.) in the perception of length occurred. There were also significant effects of viewing distance, type of surface, and orientation of the spatial intervals on the observers' judgments of surface length. The individual differences and failures of perceptual constancy that were obtained indicate that there is no single relationship between physical and perceived distances on 3-D surfaces that is consistent across observers.