Sedative-like effect of intraperitoneal GABA administration in the open field test

Gamma-Amino Butyric Acid (GABA) is the main inhibitor neurotransmitter of the Central Nervous System (CNS). Its peripheral administration has been matter of discussion. On the one hand, it has been reported that it does not cross the Blood-Brain Barrier (BBB), and, on the other hand, it has been associated with multiple therapeutic regimens and supplements by peripheral administration. The aim of the present study is to elucidate the possibility of a central sedative effect when administered peripherally. An experimental cohort of 90-day-old Holtzman male rats weighing 240-270 g was used. It was divided into 2 groups: saline-controls (n = 9) and GABA treated rats (12.5 mg/kg, n = 9). Both groups were intraperitoneally injected. The motor behavioral patterns displayed in the Opto Varimex (OVM) were studied. Vertical, horizontal, ambulatory and non-ambulatory movements and the number of movements were recorded in an automated way. Horizontal movements constitute the integration of ambulatory and non-ambulatory movements. Student t test was used comparing groups. In this experiment, there were non-significant downward trends in vertical, ambulatory, non-ambulatory and number of movements. Ambulatory and non-ambulatory tendencies acquired significance when treated together as horizontal movements (p < 0.05). We may conclude that peripheral administration of GABA produced a decrease of the horizontal movements in the open field test. It may be interpreted as a sedative effect, suggesting a passage of GABA through BBB, with central effects. However, there are several alternative possibilities to explain present findings. Other experiments will elucidate the implications or scope of the present findings.Fil: Gargiulo, Augusto Pascual Ítalo. Laboratorio de Neurociencias y Psicología Experimental; Argentina. Universidad Católica de Cuyo - Sede San Juan. Facultad de Ciencias Médicas; ArgentinaFil: Marquez Herrero, Santiago. Laboratorio de Neurociencias y Psicología Experimental; Argentina. Universidad Católica de Cuyo - Sede San Juan. Facultad de Ciencias Médicas; ArgentinaFil: Romanowicz, Esteban Alejandro. Laboratorio de Neurociencias y Psicología Experimental; Argentina. Universidad Católica de Cuyo - Sede San Juan. Facultad de Ciencias Médicas; ArgentinaFil: Guevara, Manuel Alejandro. Laboratorio de Neurociencias y Psicología Experimental; Argentina. Universidad Católica de Cuyo - Sede San Juan. Facultad de Ciencias Médicas; ArgentinaFil: Landa, Adriana Inés. Laboratorio de Neurociencias y Psicología Experimental; Argentina. Universidad Católica de Cuyo - Sede San Juan. Facultad de Ciencias Médicas; ArgentinaFil: Lafuente, José Vicente. Universidad del País Vasco; EspañaFil: Mesones, Humberto Luis. Laboratorio de Neurociencias y Psicología Experimental; Argentina. Fundación Instituto de Neurobiología; Argentina. Universidad Católica de Cuyo - Sede San Juan. Facultad de Ciencias Médicas; ArgentinaFil: Gargiulo, Pascual Angel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Laboratorio de Neurociencias y Psicología Experimental; Argentina. Universidad Católica de Cuyo - Sede San Juan. Facultad de Ciencias Médicas; Argentin

Comparative Effect between Antidepressants and D-phenylalanine, a Phenethylamine Precursor, in an Animal Model of Depression

A relevant role has been attributed to phenethylamine in depressive disorders. It has been measured in human urine and rat brain in pathological conditions and after drug administration. Furthermore, a clinical correlation has been proposed between urinary elimination and depressive symptoms. Furthermore, its metabolic predecessor, D-phenylalanine, has been used as an antidepressant drug in the treatment of depressive disorders. The use of this amino acid has been realized alone, or in combination with classical antidepressants. In the present study, we tried to characterize its behavioural profile comparing it with imipramine and fluoxetine. Antidepressant drugs have been studied using diverse animal models. We used here the Porsolt test, or Forced Swimming Test (FST), measuring times of climbing, swimming and resting. When a comparison was performed between groups in climbing behaviour, significant differences were observed between imipramine treated group and saline controls (p < 0.05), and imipramine versus fluoxetine and D-phenylalanine (p < 0.01). When swimming was evaluated, clear differences between D-phenylalanine and the other groups were observed (p < 0.001). Additionally, a significant difference was also observed between imipramine and fluoxetine (p < 0.01). When resting was evaluated, high differences between D-phenylalanine versus all other groups were shown (p < 0.001). Observed behavioural profile was according to serotonergic antidepressant drugs effects. It is supported by the fact that swimming behaviours were increased, and a correlative decrease in resting was also present. We conclude that D-phenylalanine showed higher antidepressant potency than other classical antidepressants, at least at the doses used

Biological Markers in Psychiatry and its relation with translational approaches: brief historical review

In recent years, psychiatry has attempted to find biological markers of mental illness in the strict sense or psychiatric disorders with a corporal or biological base. The purpose of this chapter is to schematically describe from the beginning the set of efforts made by biological psychiatry with the goal to find markers for mental illness, explaining the pathogenesis of these illnesses, and possibly providing new therapeutic approaches. This chapter attempts to synthetically and schematically review only a few lines of investigation in current psychiatry. It begins with a discussion about the first biochemical peripheral amines dosed, as primarily tracers or trace amines, which generated the first experiences in Argentina in the late 1960s by Fischer and colleagues. It continues with the development of the concept of windows in neuroendocrine function tests and its relevance. They were used primarily in the 1980s and we display this topic mentioning our studies on the extra hypothalamic action of hypophysotropic peptides, and the relationship of conventional transmitters with these releasing factors. Finally, we include our initial studies from the 1990s, referring to perceptual disturbances in schizophrenia, starting this new phase of exploration. It was cognitive or neuropsychological at first, with translational approaches to humanpsychoses. Finally, we describe electrophysiological exploration, including more sophisticated methods. We review briefly a field that currently has virtually unlimited proportions, hardly reducible to a single line of thought. This is a brief story of a group that had the opportunity to attend, since its inception, as a spectator of a revolution, and at times participating in direct human research approaches, and in some cases, in translational research.Fil: Gargiulo, Ángel José Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Gargiulo, Mercedes Maria Lucrecia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Ítalo Gargiulo, Augusto Pascual. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Mesones, Gonzalo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Martin, Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Landa de Gargiulo, Adriana Inés. 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. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Mesones Arroyo, Humberto Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin