Voluntary Ethanol Intake and Anxiety Behavior in Wistar-Uis Rats.

Ethanol consumption is among the first five substances with higher risk associated with diseases, disability, and death in the world. Anxiety behavior has been linked to ethanol-addictive conduct. The aim of the present study was to evaluate three strains with differential anxiety behavior: a Wild-type strain; a "Reactive" strain, with an increase in anxiety-related behaviors; and a "Non-Reactive" strain, with lower anxiety-related behaviors, before and after the voluntary consumption of ethanol (10%) protocol. To evaluate anxiety, animals were exposed to the elevated plus-maze 24 h before and after the consumption protocol. On the voluntary consumption of ethanol protocol, the animals were exposed to a water and an ethanol bottle. The weight of the liquid consumed daily for 40 days was registered. Results: all strains increased ethanol vs water consumption: Wild-type: day 8; R: day 10; NR: day 31. Ethanol consumption reduced the number and percentage of open arms entries only on the Wild-type strain. Conclusion: anxiety can predispose to an increase in ethanol consumption and to the maintenance of anxiety-related behaviors.

El consumo de alcohol se encuentra dentro de las primeras cinco sustancias con mayor riesgo asociado con enfermedades, discapacidad y muerte en el mundo. El comportamiento ansioso se ha relacionado con la conducta adictiva al alcohol. El objetivo del presente estudio fue evaluar tres cepas con conductas de ansiedad diferenciales: una cepa normal; una cepa "Reac tiva", con aumento de conductas ansiosas; y una cepa "No-Reactiva", con menor comportamiento ansioso, antes y después del protocolo de consumo voluntario de etanol (10%). Para evaluar la ansiedad, los animales fueron expuestos al laberinto en cruz elevado 24 h antes y después del protocolo de consumo. En el protocolo de consumo voluntario de etanol, los animales fueron expuestos a una botella de agua y a una de etanol. Se registró el peso del líquido consumido durante 40 días. Resultados: todas las cepas aumentaron el consumo de alcohol vs agua: General: día 8; R: día 10; NR: día 31. El consumo de etanol redujo el número y el porcentaje de entradas de brazos abiertos solo en la cepa General. Conclusión: los niveles de ansiedad pueden predisponer a un aumento del consumo de etanol y mantenimiento de comportamientos relacionados con la ansiedad.

Differentiation of action mechanisms between natural and synthetic repellents through neuronal electroantennogram and proteomic in Aedes aegypti (Diptera: Culicidae).

Natural-based compounds with repellent activity arise nowadays with the possibility to replace commercial synthetic repellents wholly or partially, such as N,N-Diethyl-m-toluamide (DEET). It is due to DEET's demonstrated toxicity and cutaneous irritation for human beings. Besides, research recommends avoiding using it with kids and pregnant women. The search for a repellent product implies early stages of detailed research that resolve the modes of action against the target insect. Therefore the objective of the current study was to analyze neuronal electrophysiological signals and olfactory system protein expression when the Aedes aegypti mosquito with exposition to natural-based repellents. Adult females of Ae. aegypti of Rockefeller strain were exposed to specific concentrations of repellent compounds like geranyl acetate, α-bisabolol, nerolidol, and DEET. The neuronal effect was measured by electroantennography technique, and the effect of exposure to either DEET or a mixture of natural molecules on protein expression was determined with 2D-PAGE followed by MALDI-TOF-mass spectrometry (MS). This approach revealed that DEET affected proteins related to synapses and ATP production, whereas natural-based repellents increased transport, signaling, and detoxification proteins. The proteomic and electrophysiology experiments demonstrated that repellent exposure disrupts ionic channel activity and modifies neuronal synapse and energy production processes.

Alpha-1 Adrenergic Receptors Modulate Glutamate and GABA Neurotransmission onto Ventral Tegmental Dopamine Neurons during Cocaine Sensitization.

The ventral tegmental area (VTA) plays an important role in the reward and motivational processes that facilitate the development of drug addiction. Presynaptic α1-AR activation modulates glutamate and Gamma-aminobutyric acid (GABA) release. This work elucidates the role of VTA presynaptic α1-ARs and their modulation on glutamatergic and GABAergic neurotransmission during cocaine sensitization. Excitatory and inhibitory currents (EPSCs and IPSCs) measured by a whole cell voltage clamp show that α1-ARs activation increases EPSCs amplitude after 1 day of cocaine treatment but not after 5 days of cocaine injections. The absence of a pharmacological response to an α1-ARs agonist highlights the desensitization of the receptor after repeated cocaine administration. The desensitization of α1-ARs persists after a 7-day withdrawal period. In contrast, the modulation of α1-ARs on GABA neurotransmission, shown by decreases in IPSCs' amplitude, is not affected by acute or chronic cocaine injections. Taken together, these data suggest that α1-ARs may enhance DA neuronal excitability after repeated cocaine administration through the reduction of GABA inhibition onto VTA dopamine (DA) neurons even in the absence of α1-ARs' function on glutamate release and protein kinase C (PKC) activation. α1-AR modulatory changes in cocaine sensitization increase our knowledge of the role of the noradrenergic system in cocaine addiction and may provide possible avenues for therapeutics.