Objective: 

Cocaine and Amphetamine Regulated Transcript (CART) is synthesized inhypothalamo-pituitary-adrenal axis which is activated in stress response. CART increases synthesis of corticotropin releasing factor (CRF), adrenocorticotropic hormone and corticosterone and the activity of the sympathetic nervous system. In this study, we aimed to show the expression of different CART peptide fragments in rat frontal cortex, brain stem, pituitary gland and adrenal gland and its regulation with acute stress.

Methods: 

In the first step, male Sprague Dawley Rats were sacrified and brains were removed. Frontal cortex, brain stem, pituitary gland and adrenal gland were dissected on ice. Total protein in each tissue sample was determined by the Nanodrop and CART peptide expression was investigated with Western Blotting.

In the second step, two groups were performed: Naïve and acute stress group which were forced to swim in 25oC water in a plexiglass cylinder for two consecutive days (n=6). CART was investigated with the same procedure.

Results: 

We showed one CART peptide fragment at 5 kD in frontal cortex, three fragments at 8 kD, 5 kD and 4 kD in pons, four fragments at 8 kD, 7 kD, 5 kD and 4 kD in medulla, four fragments at 8 kD, 7 kD, 5 kD and 4 kD in pituitary and five fragments at 13 kD, 10 kD, 8 kD, 7 kD and 5 kD in adrenal gland.

Conclusions: 

Various CART fragments are expressed in large amounts in brain regions and endocrine glands related with stress response. In our next study, we will also investigate the regulation of CART peptide fragments by forced swim stress.