Wednesday, November 4, 2009: 11:20 AM
Kohlberg (Camino Real Hotel)
The amygdala and prefrontal cortex are essential brain structures for emotional processing of sensing signs; the amygdala forms affective associations between reinforcement and punishment stimuli and prefrontal cortex process emotions associated with social and personal complex situations. Anxiety is an emotional stimulus that causes raise on metabolism and so an increase in oxygen intake thus an augmentation in the liberation of free radicals and ROS that could contribute to the development of neurodegenerative diseases. Free radicals and ROS have to be eliminated by antioxidant defenses like the enzymes: CAT, SOD and GST; these enzymes maintain an oxidant-antioxidant balance; therefore, in presence of oxidative stress caused by anxiety produced by a predator, thus these defenses should be augmented. The objective of this work was to evaluate the transcript expression, protein quantity and enzyme activity of each enzyme mentioned before in a model of anxiety stress in rats.
It has been evaluated the enzyme activity and protein quantity in amygdala and prefrontal cortex of adult rats (230-280 g) of strain Sprague Dawley exposed to predators stress by spectrofotometric specific reactions for enzyme activity and Western Blot for protein quantification. We observed a diminished enzyme activity for CAT in both tissues, whereas there was an increase in the amygdala CAT protein; for SOD we noticed an increase in enzyme activity and protein quantity for both tissues; and for GST there was an augmentation in enzyme activity just for prefrontal cortex, whilst there was no significant difference in protein quantity between treatments. These results indicate a change in antioxidant metabolism due to the anxiety produced by a predator, hence activating enzymatic defense mechanism in both tissues.