Effect of pharmacological treatment on cardiac biomarkers in patients with acute coronary syndrome of non–ST segment elevation with Type-2 diabetes

The acute coronary syndrome is a consequence of coronary artery disease. Creatine Kinase MB is a cardiac biochemical marker used in the diagnosis and risk stratification of patients. The diabetes is a pathology associated to acute coronary syndrome non–ST segment elevation that change the cardiac conditions, in this sense, our objective was to evaluate the modifications of cardiac biomarkers values in diabetic patients. Materials and methods: A retrospective study included 155 patients of both sexes, ages ranging from 31 to 92 years old, admitted to the coronary unit of the “Reina Fabiola†Clinic, Córdoba, Argentina was performed in the period 2014-2015. Body mass index, time consultation pain, plasmatic Creatine Kinase isoenzyme MB activity and Troponin I levels were measured. The patients were stratified into two groups: without cardiovascular risk pathologies (Control group), n = 7; and with only type II diabetes, n = 64 treated with therapeutic doses of metformin (n= 37), and glibenclamide plus glizipide (n= 27). Results: cTnI levels were lower in both pharmacological treatments at 12 hrs when the values in control reach the highest. Similarly, CK-MB activity was lower at 8 hrs in both treatments; however at 12 hrs these values were lower only with metformin but not in glibenclamide plus glizipide treatment. These results could be showing an interaction between diabetes and pharmacological treatment upon the biomarkers values. Conclusion: The use of hypoglycemic drugs and the glycometabolic state are conditions that could modify CK-MB and cTnI release/clearance balance at 8 and 12 hrs after admission to the coronary unit.Fil: Joison, Agustín Néstor. Universidad Catolica de Córdoba. Facultad de Ciencias Químicas; ArgentinaFil: Baiardi, Gustavo Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentin

Involment of 5HT1A receptors in the angiogenic-like effects of the Uncaria tomentosa (Willd) DC aqueous extract

1 p.The aqueous extract of Uncaria tomentosa (EUT) prepared by decoction of the root and stem bark is used in the treatment of several diseases. There is evidence showing the interaction of the extract components with serotonin receptors. Particularly, the 5HT1A receptors strongly involved in the etiology of anxiety and depression disorders. The aim of the present work was to study the involvement of 5HT1A receptors in the anxiogenic-like effect induced by the aqueous extract of Uncaria tomentosa and the influence of estrous cycle. Female albino swiss mice stereotaxically implanted with bilateral stainlesssteel cannuli into lateral ventricles were used. During 20 days, the mice were orally administered with water or EUT. It was used NAN 190 described as 5HT1A autoreceptors partial agonist and 5HT1A postsynaptic receptor antagonist. The animals receiveda 1 μl intracerebroventricular injection of vehicle or NAN 190 (0.10 μg/μl o 0.25 μg/μl). Five minutes later, the mice were tested in the elevated plus maze. The results obtained showed a significant anxiogenic effect induced by EUT and the higher dose of NAN 190 during the estrous although no differences were found when NAN 190 was administered in EUT treated animals. In the diestrous stage, the low dose of NAN 190 induced an anxiolytic effect and this response was blunted in EUT treated animals. Interestingly, an anxiolytic effect was found with the higher dose of NAN 190 in EUT treated animals. Our findings support a differential action of EUT depending on estrous cycle that could be explained as a desensitization of the 5HT1A autoreceptor induced by estrogen. Since the anxiogenic effect of EUT is observed only under desensitization conditions of 5HT1A autoreceptors, it was concluded that EUT could induce anxiety through an indirect stimulation of the raphe nucleus.Fil: Ortiz, María Julia. Universidad Católica de Córdoba. Facultad de Ciencias Químicas. Laboratorio de Neurofarmacología; Argentina.Fil: Ortiz, María Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Ponce, Andrés. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Fisiología Humana; ArgentinaFil: Bregoncio, Claudia. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacología; Argentina.Fil: Bregoncio, Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología; ArgentinaFil: Baiardi, Gustavo. Universidad Católica de Córdoba. Facultad de Ciencias Químicas. Laboratorio de Neurofarmacología; Argentina.Fil: Baiardi, Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina.Neurociencias (incluye Psicofiosiología

Renin-angiotensin sistem modulating funtions in the cpu.

The caudate-putamen (CPu) of the striatum is one of the main entrances to the basal ganglia. The CPu is fundamentally a dopaminergic area receiving dopamine innervation from the substantia nigra, ventral tegmental area, and mesencephalic structures, but also has noradrenergic inputs from a post-encephalic area, the locus coeruleus, and glutamatergic innervation from cortical structures and cholinergic and GABAergic interneurons. It is well known that functional interactions between different neurotransmission systems play a crucial integrative role in the caudate-putamen, and are widely recognized as contributing to central motor activity and movements, and also to the processing of cognitive and limbic functions, despite autonomic responses across the noradrenergic system. Not only does typical neurotransmission regulate these functions, but peptidergic systems also have an important role. The brain renin-angiotensin system (RAS) is involved not only in the regulation of blood pressure, but also in the modulation of multiple additional functions in the brain, including processes of sensory information, learning and memory, and the regulation of emotional and behavioral responses. There is increasing ontogenetic, anatomic and functional evidence of the existence of a brain renin-angiotensin system and of its interaction with other putative neurotransmitters and their receptors. All components of the RAS have been observed in the striatum, and Ang II modulates dopamine release from striatal dopaminergic terminals, in vivo and in vitro, via their AT1 receptors. There is considerable evidence supporting a key role for dopamine (DA) neurotransmission in the Cpu in long-term neuroadaptative changes induced by stress or psychostimulants, such as cocaine or amphetamine. Repeated amphetamine or cocaine administration results in progressive and enduring enhancement of their psychomotor and positive reinforcing effects (sensitization phenomenon). We recently found evidence of the participation of Ang II, through its AT1 receptors, in the development of the locomotor sensitization induced by psychostimulant drugs. Moreover, the brain RAS may play a role in the pathogenesis and progression of Parkinson?s disease and aging-related loss of DA neurons. Manipulation of RAS components may be useful for neuroprotection in Parkinson?s disease patients because local RAS plays a major role in proinflammatory and pro-oxidative changes in aged substantia nigra. RAS is involved in modulating neurotransmission systems in the CPu and their functions, and for this reason it could be a possible target in the treatment of stress related diseases, drug abuse or neurodegenerative disorders.http://www.novapublishers.com/catalog/product_info.Fil: Bregonzio, Claudia. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacología, ArgentinaFil: Bregonzio, Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Farmacología Experimental de Córdoba, Argentina.Fil: Marinzalda, M. A. Universidad Católica de Córdoba. Facultad de Ciencias Químicas. Laboratorio de Neurofarmacología, Argentina.Fil: Baiardi, Gustavo.Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales, ArgentinaFil: Baiardi, Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Biológicas y Tecnológicas, Argentina.Fil: Baiardi, Gustavo. Universidad Católica de Córdoba. Facultad de Ciencias Químicas. Laboratorio de Neurofarmacologia, Argentina.Fil: Paz, María Constanza. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Farmacología Experimental de Córdoba, Argentina , Argentina.Fil: Paz, María Constanza. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacología, ArgentinaNeurociencias (incluye Psicofiosiología

From brain to kidney: Central AT1 receptors and sympathetic nervous system interaction in sodium excretion mechanisms

Central angiotensin II through AT1 receptors (AT1-R), closely interact with sympathetic nervous system (SNS) in the maintenance of renal sodium equilibrium under normal and pathological conditions. Our aim was to unmask the brain AT1-R role in the renal sodium excretion mechanisms and the interaction with the SNS. For these purposes, male Wistar rats with renal nervous ablation/sham and implanted with bilateral cannulae in lateral ventricle, received normosodic (0.4 %) or hypersonic (4 %) diet in metabolic cages for 5 days. The surgical procedures were performed under ketamine/xylaxine (75/5 mg/kg i.p.) anesthesia. The urine was daily collected and water intake was register along the experiment. On day 6 the animals received saline/losartan (AT1- R antagonist 4ug/1 μl) intracerebrally and sacrificed 12 hours later. The parameters analyzed were; in urine: volume, sodium, potassium, water, creatinine and osmolarity to evaluate kidney function; at brain: c-Fos expression in paraventricular (PVN), supraoptic (SON) and subfornical (SFO) nucleus and vasopressin by immunohistochemistry. The data were analyzed by factorial ANOVA. The effects of central AT1-R and the interaction with SNS were observed on water intake and sodium and water excretion. Renal sodium excretion and water intake are under central AT1-R activation depending on renal nervous integrity. AT1-R blockade blunted the increased c-Fos expression induced by hypersodic diet in vasopressinergic neurons (PVN and SON). We conclude that SNS regulates the complex interaction between central angiotensin II, through AT1-R, and vasopressinergic neurons at SON and PVN under sodium overload conditions.Fil: Ruberto, Celia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Occhieppo, Victoria Belen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Farmacología Experimental de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Farmacología Experimental de Córdoba; ArgentinaFil: Basmadjian, Osvaldo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Farmacología Experimental de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Farmacología Experimental de Córdoba; ArgentinaFil: Bregonzio, Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Farmacología Experimental de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Farmacología Experimental de Córdoba; ArgentinaFil: Baiardi, Gustavo Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaReunión Anual de Sociedades de BiocienciaMar del PlataArgentinaSociedad Argentina de Investigación ClínicaAsociación Argentina de Farmacología ExperimentalSociedad Argentina de BiologíaSociedad Argentina de ProtozoologíaAsociación Argentina de Nanomedicina

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

Amphetamine induced differential effects in vascular and glial components at somatosensory cortex: Why to focus on AT1 receptors

Amphetamine (Amph), is associated with inflammatory processes, involving glial and vascular alterations. Brain Angiotensin II, through AT1-receptors (AT1-R), modulates dopaminergic neurotransmission and plays a crucial role in inflammatory responses. Our aim was to evaluate the role of AT1-R in long-term alterations induced by repeated exposure to Amph. Astrocyte and microglia reactivity, and brain microvascular network were analysed at the somatosensory cortex (S1 Barrel and S1 Trunk area). Male Wistar rats (250–320 g) were administered with AT1-R antagonist Candesartan/vehicle (3 mg/kg p.o., days 1–10) and Amph/saline (2.5 mg/kg i.p., days 6–10). The four experimental groups at the two times evaluated (17 and 31 days) were: Veh-Sal, CV-Sal, Veh-Amph, CV-Amph. On days 17 and 31 the animals were sacrificed and their brains were processed for immunohistochemistry against GFAP (astroglial marker), CD11b (microglial marker) and von Willebrand factor (vascular marker). Data were analysed with factorial ANOVA followed by Bonferroni test. Our results indicate that Amph exposure induces an endurable increase in astrocyte and microglia reactivity at S1 Barrel and S1 Trunk area. Although, the microvascular rearrangement (evaluated as vascular area density, branching points and tortuosity) showed time dependant differential response to Amph, since at day 31 these parameters return to basal conditions at S1 Barrel. Meanwhile, at S1 Trunk the vascular changes were observed only at day 31. Pretreatment with the AT1-R blocker prevented the described alterations induced by Amph. We conclude that neuroplastic changes induced by Amph demand an AT1-R active role showing a regional susceptibility at vascular level.Fil: Armonelli Fiedler, Samanta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Farmacología Experimental de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Farmacología Experimental de Córdoba; ArgentinaFil: Occhieppo, Victoria Belen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Farmacología Experimental de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Farmacología Experimental de Córdoba; ArgentinaFil: Basmadjian, Osvaldo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Farmacología Experimental de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Farmacología Experimental de Córdoba; ArgentinaFil: Bregonzio Diaz, Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Farmacología Experimental de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Farmacología Experimental de Córdoba; ArgentinaFil: Baiardi, Gustavo Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaReunión anual de sociedades de BiocienciaMar 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

Angiotensin II modulates amphetamine‐induced glial and brain vascular responses, and attention deficit via Angiotensin Type 1 receptor: evidence from brain regional sensitivity to amphetamine

Amphetamine‐induced neuroadaptations involve vascular damage, neuroinflammation, a hypo‐functioning prefrontal cortex (PFC) as well as cognitive alterations. Brain angiotensin II, through Angiotensin Type 1 receptor (AT1‐R), mediates oxidative/inflammatory responses, promoting endothelial dysfunction, neuronal oxidative damage and glial reactivity. The present work aims to unmask the role of AT1‐R in the development of amphetamine‐induced changes over glial and vascular components within PFC and hippocampus. Attention deficit was evaluated as a behavioral neuroadaptation induced by amphetamine. Brain microvessels were isolated to further evaluate vascular alterations after amphetamine exposure. Male Wistar rats were administered with AT1‐R antagonist, Candesartan, followed by repeated amphetamine. After one week drug‐off period, animals received a saline or amphetamine challenge and were evaluated in behavioral tests. Afterwards, their brains were processed for cresyl violet staining, CD11b (microglia marker), GFAP (astrocyte marker) or von Willebrand factor (vascular marker) immunohistochemistry, and oxidative/cellular stress determinations in brain microvessels. Statistical analysis was performed by using Factorial ANOVA followed by Bonferroni or Tukey tests. Repeated amphetamine administration increased astroglial and microglial markers immunoreactivity, increased apoptotic cells and promoted vascular network rearrangement at the PFC concomitantly with an attention deficit. Although, the amphetamine challenge improved the attentional performance, it triggers detrimental effects probably because of the exacerbated malondialdehyde levels and increased heat shock protein 70 expression in microvessels. All observed amphetamine‐induced alterations were prevented by the AT1‐R blockade. Our results support the AT1‐R involvement in the development of oxidative/inflammatory conditions triggered by amphetamine exposure, affecting cortical areas and increasing vascular susceptibility to future challenges.Fil: Marchese, Natalia Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Farmacología Experimental de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Farmacología Experimental de Córdoba; ArgentinaFil: Occhieppo, Victoria Belen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Farmacología Experimental de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Farmacología Experimental de Córdoba; ArgentinaFil: Basmadjian, Osvaldo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Farmacología Experimental de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Farmacología Experimental de Córdoba; ArgentinaFil: Casarsa, Brenda Solange. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Baiardi, Gustavo Carlos. Universidad Católica de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Bregonzio Diaz, Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Farmacología Experimental de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Farmacología Experimental de Córdoba; Argentin

Estudio de las respuestas neurofisiológicas y conductuales integradas en el sistema límbico: participación de los neuropéptidos derivados de la pre pro MCH y Angiotensina II

Numerosos estudios indican que la amígdala, se encuentra estrechamente ligada a la generación y modulación de los procesos emocionales. Aunque el complejo de la amígdala generalmente se define por varios grupos distintos de células, los núcleos de la amígdala basolateral que se conectan con el núcleo central y el núcleo de la estría terminal son los que proyectan a las áreas del sistema nervioso central involucradas en el control de las respuestas autónomas, los procesos cognitivos y la respuesta emocional. Además de los ampliamente estudiados sistemas glutamatérgico, gabaérgico, endorfinérgico, CRH, CCK entre otros, en estas áreas de la amígdala se encuentran receptores AT1 del sistema renina-angiotensina cerebral y llegan fibras del sistema de la pre-pro-hormona MCH (ppMCH) de la que se derivan la hormona concentradora de melanina (MCH) y otros dos péptidos biológicamente activos: el neuropéptido glicina (G)-ácido glutámico (E) (NGE) y el neuropéptido glutamina (E)- isoleucina (I) (NEI). Entre las áreas a las que se proyectan los núcleos de la amígdala se destaca la inervación de núcleos dopaminérgicos a través del área tegmental ventral y su influencia sobre la función del eje hipotálamo-hipófiso-adrenal (HHA) por la modulación de la descarga de ACTH a través de la inervación del núcleo hipotalámico paraventricular. Este proyecto tiene como objetivo evaluar los efectos de los neuropéptidos derivados de la ppMCH y Angiotensina II en la amígdala basolateral, sobre: el estado de ansiedad, conducta de exploración, activación del eje HHA y la trasmisión dopaminérgica en las áreas de proyección de la amígdala. Se empleará un modelo de miedo potenciado en ratas, que provoca una mayor activación de la amígdala y el establecimiento de un estado de ansiedad por la exposición previa a una situación de estrés. En este modelo se desencadenan respuestas similares a las encontradas en pacientes que sufren desórdenes de ansiedad, lo que nos permite estudiar el rol de los neuromoduladores en su fisiopatogenia

Vibrationally resolved NEXAFS at C and N K-edges of pyridine, 2-fluoropyridine and 2,6-difluoropyridine: A combined experimental and theoretical assessment

In the present work, the near edge X-ray absorption spectroscopy (NEXAFS) spectra at both C and N K-edges of pyridine, 2-fluoropyridine, and 2,6-difluoropyridine have been studied both experimentally and theoretically. From an electronic point of view, both transition potential density functional theory and time-dependent density functional theory approaches lead to reliable results provided that suitable basis sets and density functionals are employed. In this connection, the global hybrid B3LYP functional in conjunction with the EPR-III basis set appears particularly suitable after constant scaling of the band positions. For the N K-edge, vertical energies obtained at these levels and broadened by symmetric Gaussian distributions provide spectra in reasonable agreement with the experiment. Vibronic contributions further modulate the band-shapes leading to a better agreement with the experimental results, but are not strictly necessary for semi-quantitative investigations. On the other hand, vibronic contributions are responsible for strong intensity redistribution in the NEXAFS C K-edge spectra, and their inclusion is thus mandatory for a proper description of experiments. In this connection, the simple vertical gradient model is particularly appealing in view of its sufficient reliability and low computational cost. For more quantitative results, the more refined vertical Hessian approach can be employed, and its effectiveness has been improved thanks to a new least-squares fitting approach

Estudio de las respuestas neurofisiológicas y conductuales integradas en el sistema límbico: participación de los neuropéptidos derivados de la pre pro MCH y Angiotensina II

Numerosos estudios indican que la amígdala, se encuentra estrechamente ligada a la generación y modulación de los procesos emocionales. Aunque el complejo de la amígdala generalmente se define por varios grupos distintos de células, los núcleos de la amígdala basolateral que se conectan con el núcleo central y el núcleo de la estría terminal son los que proyectan a las áreas del sistema nervioso central involucradas en el control de las respuestas autónomas, los procesos cognitivos y la respuesta emocional. Además de los ampliamente estudiados sistemas glutamatérgico, gabaérgico, endorfinérgico, CRH, CCK entre otros, en estas áreas de la amígdala se encuentran receptores AT1 del sistema renina-angiotensina cerebral y llegan fibras del sistema de la pre-pro-hormona MCH (ppMCH) de la que se derivan la hormona concentradora de melanina (MCH) y otros dos péptidos biológicamente activos: el neuropéptido glicina (G)-ácido glutámico (E) (NGE) y el neuropéptido glutamina (E)- isoleucina (I) (NEI). Entre las áreas a las que se proyectan los núcleos de la amígdala se destaca la inervación de núcleos dopaminérgicos a través del área tegmental ventral y su influencia sobre la función del eje hipotálamo-hipófiso-adrenal (HHA) por la modulación de la descarga de ACTH a través de la inervación del núcleo hipotalámico paraventricular. Este proyecto tiene como objetivo evaluar los efectos de los neuropéptidos derivados de la ppMCH y Angiotensina II en la amígdala basolateral, sobre: el estado de ansiedad, conducta de exploración, activación del eje HHA y la trasmisión dopaminérgica en las áreas de proyección de la amígdala. Se empleará un modelo de miedo potenciado en ratas, que provoca una mayor activación de la amígdala y el establecimiento de un estado de ansiedad por la exposición previa a una situación de estrés. En este modelo se desencadenan respuestas similares a las encontradas en pacientes que sufren desórdenes de ansiedad, lo que nos permite estudiar el rol de los neuromoduladores en su fisiopatogenia.Fil: Baiardi, Gustavo Carlos. Universidad Católica de Córdoba. Facultad de Ciencias Químicas, Argentin