Abstract
The SFO is implicated in peripheral T cell activation and the genesis of Ang-II-dependent hypertension. Our recent studies show that ER stress in the SFO is also a key mechanism underlying the development of Ang-II hypertension. Because the ER is closely integrated with initiation of the adaptive immune response, we hypothesized that ER stress in the SFO contributes to peripheral inflammation in Ang-II hypertension. First, 5 days of intracerebroventricular (ICV) infusion of thapsigargin (Tg, 1 ug/day), a chemical ER stress inducer, caused a significant increase in CD3 + T cells in aortas (Tg: 11.9 ± 3.5 x 10 3 cells/aorta vs. Vehicle: 2.2 ± 0.7 x 10 3 cells/aorta , n = 6, p<0.05) and blood (Tg: 9.9 ± 1.8 x 10 4 cells/ mL vs. Vehicle: 2.9 ± 0.6 x 10 4 cells/ mL, n = 6, p<0.05). Furthermore, quantitative real-time PCR of SFO micropunches showed a 15-fold increase of TNF-α, a pro-inflammatory cytokine, a 3-fold increase of CCL5, a T cell attracting chemokine and a 3-fold increase in CD3, a T cell marker, (n = 4, p<0.05). To test the functional role of ER stress in the SFO in peripheral T cell activation, we targeted an adenovirus encoding GRP78 (AdGRP78), a molecular ER stress inhibitor, to this brain region during chronic systemic Ang-II infusion (600 ng/kg/min, 14 days). Our results demonstrate a significant reduction in T cell accumulation in aortas compared to control virus (AdLacZ) treatment (AdGRP78: 0.5 ± 0.07 x 10 4 cells/aorta vs. AdLacZ: 8.7 ± 2.1 x 10 4 cells/aorta, n = 6, p<0.05). These data show that 1) brain ER stress induces inflammation in the SFO and peripheral vascular T cell activation, and 2) ER stress in the SFO is linked to peripheral vascular T cell activation in Ang-II-dependent hypertension. These results suggest that ER stress and inflammation in the SFO induce peripheral vascular T cell activation and inflammation in Ang-II hypertension.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
