Pharmacological effect of one icv dose of Allopregnanolone in female rat: behavioural profile

We have previously observed that intracerebroventricular allopregnanolone (ALLO) injection produced an anxiolytic effect and inhibited sexual receptivity when the test was performed in a separate manner. Also, ALLO reverts learning deficit in female rats in the hippocampi. To study the behavioral effects of an acute treatment with ALLO in the right lateral ventricle we used two approaches: a- A battery test to analyze the anxiety and mating behavior. And b- The avoidance test and novel object recognition test to evaluate its effect on memory and learning. Ovariectomized rats were injected with estrogen and progesterone. After it ALLO or vehicle were administered into the right lateral ventricle. To reach the objective (a) rats were put in a sequential battery test in the next order: 1-Open field. 2- Plus maze task. 3- Mating behavior. For the aim (b) it was performed a Novel Object Recognition Test and Step-down Inhibitory Avoidance Task. ALLO did not affect locomotors-exploratory behavior. Animals treated with ALLO, spent more time and had more entries into the open arm in a plus maze task and lordosis quotient was lower than in the control group. ALLO increased the latency in step down test and had no effects on discrimination index test in NORT. Here we demonstrated that one pharmacological dose of ALLO in ovariectomized primed rats is enough to generate all changes observed in the battery test. Moreover, the acute treatment with ALLO in lateral ventricle enhanced the memory acquisition in an avoidance task.Fil: Pelegrina, Laura Tatiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Escudero, Carla Gimena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Giuliani, Fernando Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: García Menéndez, Sebastián Marcelo Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Cabrera Kreiker, Ricardo Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Laconi, Myriam Raquel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin

A single dose of allopregnanolone affects rat ovarian morphology and steroidogenesis

Allopregnanolone, a progesterone metabolite, is one of the best characterized neurosteroids. In a dose that mimics serum levels during stress, allopregnanolone inhibits sexual receptivity and ovulation and induces a decrease in luteinizing hormone levels. The aim of this work was to examine the effect of an intracerebroventricular administration of allopregnanolone on ovarian morphophysiology; serum and tissue levels of progesterone and estrogen; and enzymatic activity of 3β-hydroxysteroid dehydrogenase, 20α-hydroxysteroid dehydrogenase and 3α-hydroxysteroid oxido-reductase in the ovary and in the medial basal hypothalamus on the morning of estrus. Ovarian morphology was analyzed under light microscopy. The hormone assays were performed by radioimmunoassay. The enzymatic activities were measured by spectrophotometric analysis. The morphometric analysis revealed that, in allopregnanolone-treated animals, the number of secondary and Graafian follicles was decreased, whereas that of atretic follicles and cysts was significantly increased. Some cysts showed luteinized unruptured follicles. There were no differences in the number of tertiary follicles or corpora lutea in comparison with the corresponding control groups. In allopregnanolone-treated animals, progesterone serum levels were increased, whereas ovarian progesterone levels were decreased. Moreover, 3β-HSD and 3α-HSOR enzymatic activities were increased in the medial basal hypothalamus, whereas ovarian levels were decreased. The enzyme 20α-hydroxysteroid dehydrogenase showed the opposite profile. The results of this study showed that allopregnanolone interferes on ovarian steroidogenesis and ovarian morphophysiology in rats, providing a clear evidence for the role of this neurosteroid in the control of reproductive function under stress situations.Fil: Pelegrina, Laura Tatiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Cáceres Gimenez, Antonella Rosario Ramona. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Giuliani, Fernando Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Asensio, Joana Antonela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Parborell, Maria Fernanda Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Laconi, Myriam Raquel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

Neuromodulatory effect of progesterone on the dopaminergic, glutamatergic, and GABAergic activities in a male rat model of Parkinson's disease

Objectives: Progesterone has been reported to have a neuroprotective role in depression-like rats in a hemiparkinsonian model of the disease. In this work, we investigate if this hormone affects the three principal neurochemicals striatal systems (dopaminergic, glutamatergic, and GABAergic) that are involved in the physiopathology of the disease in a hemiparkinsonim male rat model at 8 weeks post-chemical injury. Methods: For this purpose, we design three experimental groups: (1) sham group; (2) hemiparkinsonian group; and (3) hemiparkinsonian group subcutaneously injected with progesterone at 7 days post- chemical injury. Animals were tested in an automated rotational device at 8 weeks post-chemical injury. After behavioral test, Kz-evoked [3H]-dopamine, [3H]-glutamate, and [3H]-gamma aminobutyric acid release from striatum slices were analyzed by superfusion experiments. Results: The hemiparkinsonian group showed distinctive alterations that are produced by neurodegenera- tion of left nigrostriatal dopaminergic pathway by 6-hydroxydopamine hydrobromide (6-OHDA). On the other hand, the administration of progesterone 7 days after the injection of the neurotoxin was able to (1) improve the Kz-evoked [3H]-dopamine release from the damaged striata (left); (2) avoid significant increase in the Kz-evoked [3H]-glutamate release from the left striata; and (3) progesterone does not modify the Kz-evoked [3H]-gamma aminobutyric acid release from the left striata. Discussion: These results suggest that progesterone does have neuroprotective and neuromodulatory effects on striatal neurotransmission systems in the hemiparkinsonian male rats. The possible mechanisms would involve genomic and non-genomic actions of this neuroactive steroid which would modulate the activity of dopaminergic, glutamatergic, and GABAergic pathways.Fil: Casas, Sebastián Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina; Universidad de Mendoza. Facultad de Ciencias Médicas. Instituto de Investigaciones Biomédicas; Argentina;Fil: Giuliani, Fernando Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina; Universidad de Mendoza. Facultad de Ciencias Médicas. Instituto de Investigaciones Biomédicas; Argentina;Fil: Cremaschi, Fabián. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Area de Neurología Clínica y Quirúrgica; Argentina;Fil: Yunes, Roberto Miguel Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina; Universidad de Mendoza. Facultad de Ciencias Médicas. Instituto de Investigaciones Biomédicas; Argentina;Fil: Cabrera, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina; Universidad de Mendoza. Facultad de Ciencias Médicas. Instituto de Investigaciones Biomédicas; Argentina

Allopregnanolone reversion of estrogen and progesterone memory impairment: interplay with serotonin release

Previously, we found out that in ovariectomized female rats, estrogen and progesterone produce a memory deficit which is reverted by the intrahippocampal administration of allopregnanolone. Here, we study the possible interplay between allopregnanolone and hippocampal serotonergic activity. Ovariectomized rats injected subcutaneously with estrogen and progesterone were subsequently injected in the dorsal hippocampus with vehicle, allopregnanolone alone or allopregnanolone shortly after 8OH-DPAT, a predominantly 5HT1A-7 receptor agonist. Then, the subjects were sequentially tested in: (1) an inhibitory avoidance task and (2) K+-evoked [3H]-serotonin ex vivo release through superfusion experiments. Allopregnanolone increased the K+-evoked [3H]-serotonin release compared to control. 8OH-DPAT infusions reversed the effects of allopregnanolone on memory and K+-evoked [3H]-serotonin release. These results suggest that allopregnanolone memory improvement could be mediated, at least in part, through modulation of the hippocampal serotonergic system reactivity.Fil: Escudero, Carla Gimena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Giuliani, Fernando Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Mulle Bernedo, María Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Yunes, Roberto Miguel Federico. 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: Cabrera Kreiker, Ricardo Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin

Allopregnanolone prevents memory impairment: Effect on mRNA expression and enzymatic activity of hippocampal 3-α hydroxysteroid oxide-reductase

In this work we investigated how the neurosteroid allopregnanolone can modulate learning and memory processes. For this purpose, we used ovariectomized (OVX) rats subcutaneously injected with oestradiol benzoate (E) alone or E and progesterone (P). Then, rats were injected in dorsal hippocampus with allopregnanolone or vehicle. Animals were tested in inhibitory avoidance task (IA task). After behavioural test hippocampal mRNA expression and enzymatic activity of 3-HOR, the enzyme responsible of allopregnanolone synthesis, were analysed. In IA task OVX-EP rats spent less time on platform, compared to those OVX or OVX-E. Regression analyses revealed that there was a significant negative relationship between E-P infusion and performance in this task. Pre-training allopregnanolone administration to OVX-EP rats increased the time spent on the platform. Interestingly, when enzymatic activity of 3-HOR was tested, OVX-EP rats showed a significant decrease in the enzymatic activity, compared with OVX and OVX-E rats. In addition, OVX-EP group showed a significant increase in the enzymatic activity after intrahippocampal infusion of allopregnanolone. On the other hand, when mRNA expression of 3-HOR was analysed no differences were observed when the hippocampal allopregnanolone injection was done. These results suggest that E and P have amnesic effects on female rats, being reversed by allopregnanolone through its modulation on hippocampal 3-HOR activity.Fil: Escudero, Carla Gimena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad de Mendoza; ArgentinaFil: Casas, Sebastián Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad de Mendoza; ArgentinaFil: Giuliani, Fernando Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad de Mendoza; ArgentinaFil: Bazzocchini, Vanesa Silvana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad de Mendoza; ArgentinaFil: García, Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad de Mendoza; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; ArgentinaFil: Yunes, Roberto Miguel Federico. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; Argentina. Universidad de Mendoza; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Cabrera Kreiker, Ricardo Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad de Mendoza; Argentin

Allopregnanolone and puberty: modulatory effect on glutamate and GABA release and expression of 3-hydroxysteroid oxidoreductase in the hypothalamus of female rats.

The hypothalamic release of glutamate and GABA regulates neurosecretory functions that may control the onset of puberty. This release may be influenced by neurosteroids such as allopregnanolone. Using superfusion experiments we examined the role of allopregnanolone on the K+-evoked and basal [3H]-glutamate and [3H]-GABA release from mediobasal hypothalamus and anterior preoptic area in prepubertal, vaginal opening and pubertal (P) rats and evaluated its modulatory effect on GABAA and NMDA (N-methyl-d-aspartic acid) receptors. Also, we examined the hypothalamic activity and mRNA expression of 3α-hydroxysteroid oxidoreductase (3α-HSOR) ? enzyme that synthesizes allopregnanolone ? using a spectrophotometric method and RT-PCR, respectively. Allopregnanolone increased both the K+-evoked [3H]-glutamate and [3H]-GABA release in P rats, being the former effect mediated by the modulation of NMDA receptors ? as was reverted by Mg2+ and by the NMDA receptor antagonist AP-7 and the latter by the modulation of NMDA and GABAA receptors ? as was reverted by Mg2+ and the GABAA receptor antagonist bicuculline. The neurosteroid also increased the basal release of [3H]-glutamate in VO rats in an effect that was dependent on the modulation of NMDA receptors as was reverted by Mg2+. On the other hand we show that allopregnanolone reduced the basal release of [3H]-GABA in P rats although we cannot elucidate the precise mechanism by which the neurosteroid exerted this latter effect. The enzymatic activity and the mRNA expression of 3α-HSOR were both increased in P rats regarding the other two studied stages of sexual development. These results suggest an important physiological function of allopregnanolone in the hypothalamus of the P rat where it might be involved in the ?fine tuning? of neurosecretory functions related to the biology of reproduction of the female rats.Fil: Giuliani, Fernando Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Escudero, Carla Gimena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Casas, Sebastián Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Bazzocchini, Vanesa Silvana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Yunes, Roberto Miguel Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Área de Farmacología; ArgentinaFil: Laconi, Myriam Raquel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Cabrera Kreiker, Ricardo Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin

La estimulación gabaérgica del núcelo septal lateral del cerebro de ratas macho disminuye la inhibición al miedo frente a estímulos normalmente neutros

El núcleo septal lateral forma parte de estructuras subcorticales del cerebro.  La destrucción de dicho núcleo  genera lo que se conoce como síndrome de furia septal. En este trabajo demostramos que el agonista GABAérgico muscimol, en dosis no sedativas, indujo una inhibición del miedo en ratas macho de la cepa Sprague-Dawley, asociada a un aumento de respuestas agresivas a objetos habitualmente neutros. Estos resultados, sumados al hecho de que el núcleo septal lateral participa en diversas entidades psiquiátricas, hace que sea interesante aportar al conocimiento de su función apelando a moduladores que se sabe están presentes en el en dicha estructura del sistema nervioso central.Destruction of lateral septum –a nucleus located in subcortical regions of the anterior brain– has been related to an entity known as rage septal syndrome. In the present paper we demonstrate that the direct GABAergic agonist muscimol produces “fear inhibition” when tested at non-sedative doses in Sprague-Dawley male rats. This phenomenon is also supported by an increase of aggressive behaviors directed to otherwise neutral objects. Since the septal lateral has been involved in several psychiatric diseases, it appears as potentially interesting to contribute to the knowledge of its function by taking advantage of eventual modulators known to be present in the nucleus.Fil: Nanfaro, Federico. 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: Bazzocchini, Vanesa Silvana. 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; Argentina. Universidad de Mendoza; ArgentinaFil: Vega, Adriana. 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: Giuliani, Fernando Alfredo. 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: Laconi, Myriam Raquel. 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: Casas, Sebastián Marcelo. Universidad de Mendoza; ArgentinaFil: Escudero, Carla Gimena. 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: Cabrera Kreiker, Ricardo Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universidad de Mendoza; ArgentinaFil: Yunes, Roberto Miguel Federico. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin