Finasteride administration potentiates the disruption of prepulse inhibition induced by forced swim stress
Behavioural Brain Research. 2015-08-01; 289: 55-60
DOI: 10.1016/j.bbr.2015.04.023
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Pallarès M(1), Llidó A(2), Mòdol L(3), Vallée M(4), Darbra S(2).
Author information:
(1)Departament de Psicobiologia i Metodologia de les Ciències de la Salut,
Institut de Neurociències, Universitat Autònoma de Barcelona, Edifici B, campus
UAB, 08193 Bellaterra, Barcelona, Spain. Electronic address:
.
(2)Departament de Psicobiologia i Metodologia de les Ciències de la Salut,
Institut de Neurociències, Universitat Autònoma de Barcelona, Edifici B, campus
UAB, 08193 Bellaterra, Barcelona, Spain.
(3)Present address: INMED, INSERM U901, Aix-Marseille Université, Parc
Scientifique de Luminy, BP.13, 13273 Marseille cedex 9, France.
(4)Institut National de la Santé et de la Recherche Medicale (INSERM), Unité
862, Bordeaux, France.
Acute stress has been demonstrated to alter sensory gating processes, measured
by the prepulse inhibition of the startle response (PPI). It is well known that
brain and plasma levels of the neurosteroid allopregnanolone (ALLO) increase
after acute environmental stress, fact that has been considered a homeostatic
mechanism in restoring normal function following stress. Thus, it is of great
interest to study the contribution of stress-altered plasma ALLO levels on PPI
function. For this purpose, animals were injected with finasteride, an ALLO
synthesis inhibitor, and submitted to swim stress before PPI testing. In order
to obtain ALLO plasma levels, a separate set of animals that followed the same
experimental procedure was used. We hypothesize that the blockade of ALLO
production in response to stress can increase the stress-induced PPI disruption.
In accordance with other authors, our results indicate that acute swim stress
disrupted the normal PPI evolution (increase) related to the increase in
prepulse intensities, and also decreased PPI at the highest prepulse intensity
level (15 db above background). Finasteride potentiated the PPI decrease induced
by swim stress in the intermediate prepulse intensity (10 db above background).
As expected, plasma ALLO levels were increased in stressed animals and this
increase was neutralized by prior finasteride administration. These results
indicate that the neutralization of the physiological plasma ALLO levels
increase after acute stress potentiates stress-induced PPI disruption. This data
suggests that alterations in homeostatic ALLO synthesis mechanism may be linked
to some neuropsychiatric disorders related to stress, such as anxiety/depression
disorders.
Copyright © 2015 Elsevier B.V. All rights reserved.