Behavior of rats with ankle immobilized at 90° submitted to electric muscle stimulation
Keywords:
Behavior, Immobilization, Plus maze, RatsAbstract
Objective
The objective of this study was to evaluate the behavior (exploratory activity in
open field) and anxiety indexes (elevated plus maze) of rats submitted to 5 days
of immobilization with an acrylic resin orthesis and session of electric stimulation.
Methods
Three-month-old Wistar rats obtained from the Methodist University of Piracicaba|
animal facility, were kept under controlled laboratory conditions, with water and
rodent chow ad libitum and a 12h light/dark cycle and divided into 4 groups:
control, immobilized, electrically stimulated, and immobilized and electrically
stimulated, n=8. Statistical analysis was done by ANOVA and the Tukey test
(p<0.05). The rats were anesthetized (sodium pentobarbital 50mg/kg, ip), a blood
sample was collected and the plasma separated in order to evaluate plasmatic
concentration of corticosterone by the ELISA method.
Results
The control group demonstrated a reduction in exploratory activity in the open
field test and a low concentration of plasmatic corticosterone, while the
immobilized group displayed reduced exploratory activity in the open field and
elevated plasmatic concentration of corticosterone. In this sense, the electrically
stimulated group was not different from the control, while the immobilized
and electrically stimulated groups demonstrated an increase in exploratory
activity in the open field in comparison with the immobilized group. In the
elevated plus maze analysis, the immobilized group showed an elevation in
anxiety indexes, which was less intense in the immobilized and electrically stimulated
group.
Conclusion
The results illustrate that immobilization reduces exploratory activity in the open
field and generates anxiety, while electrical stimulation improved exploratory
activity in the open field and reduced anxiety. This can be related to improvement
in the metabolic conditions of the musculature.
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References
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