González-Piña R, Alfaro-Rodríguez A, Bueno-Nava A, Ávila-Luna A

Language: Spanish
References: 20
Page: 28-32
PDF size: 201.06 Kb.

ABSTRACT

Introduction: It has been proposed that noradrenaline is one of the neurotransmitters involved in the functional recovery. In this sense, it has been proposed that the alpha-2 noradrenergic receptors play an important role in the functional reinstatement.
Objective: the aim of this work was to study the role of the alpha-2 noradrenergic receptors on the noradrenaline contents in cerebellum and pons of rats iron-injured in the motor cortex.
Methods: Fifteen male Wistar rats were allocated in three groups: control (n = 5) with intracortical infusion of saline (0.9%), injured (n = 5) with intracortical infusion of dextran iron and intraventricular infusion of saline, and injured + yohimbine (alpha-2 receptor’s antagonist; n = 5) that received an intracortical infusion of dextran iron and also an intraventricular infusion of yohimbine. Motor behavior was assessed by means of the beam-walking paradigm. Three days after surgeries, the animals were sacrificed and the left and right sides of the pons and the cerebellar hemispheres were extracted. Tissues were prepared for noradrenaline analysis by means of high performance liquid chromatography.
Results: We observed that the yohimbine-treated animals had a noradrenaline increase in the right side of the pons and a decrease in the right cerebellar hemisphere.
Conclusion: It is concluded that the blockage of the alpha-2 receptors leads to an increase of noradrenaline in the locus coeruleus, which retards the effects of the cerebral injury.

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