Chronic stress induces upregulation of brain-derived neurotrophic factor (BDNF) mRNA and integrin alpha5 expression in the rat pineal gland.
Chronic stress affects brain areas involved in learning and emotional responses. These alterations have been related with the development of cognitive deficits in major depression. Moreover, stress induces deleterious actions on the epithalamic pineal organ, a gland involved in a wide range of physiological functions. The aim of this study was to investigate whether the stress effects on the pineal gland are related with changes in the expression of neurotrophic factors and cell adhesion molecules. Using reverse transcription-polymerase chain reaction (RT-PCR) and Western blot, we analyzed the effect of chronic immobilization stress on the BDNF mRNA and integrin alpha5 expression in the rat pineal gland. We found that BDNF is produced in situ in the pineal gland. Chronic immobilization stress induced upregulation of BDNF mRNA and integrin alpha5 expression in the rat pineal gland but did not produce changes in beta-actin mRNA or in GAPDH expression. Stressed animals also evidenced an increase in anxiety-like behavior and acute gastric lesions. These results suggest that BDNF and integrin alpha5 may have a counteracting effect to the deleterious actions of immobilization stress on functionally stimulated pinealocytes. Furthermore, this study proposes that the pineal gland may be a target of glucocorticoid damage during stress.
Dagnino-Subiabre
Alexies
A
Department of Psychiatry and Center for Medical Research, Faculty of Medicine, Pontificia Universidad Católica de Chile, Ave. Marcoleta N 387, piso 2, Casilla 114-D, Santiago 1, Chile. adagnino@med.puc.cl
Zepeda-Carreño
Rodrigo
R
Díaz-Véliz
Gabriela
G
Mora
Sergio
S
Aboitiz
Francisco
F
D000818:Animals; D001522:Behavior, Animal; D015153:Blotting, Western / Q000379:methods; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression / Q000502:physiology*; D039482:Integrin alpha5 / Q000235:genetics / Q000378:metabolism*; D008297:Male; D018782:Maze Learning / Q000502:physiology; D009043:Motor Activity / Q000502:physiology; D010870:Pineal Gland / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012149:Restraint, Physical / Q000379:methods; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013315:Stress, Psychological / Q000503:physiopathology*; D015854:Up-Regulation / Q000502:physiology*
D019208:Brain-Derived Neurotrophic Factor; D039482:Integrin alpha5; D012333:RNA, Messenger