| Full text | |
| Author(s): |
Fragas, Matheus Garcia
[1]
;
Candido, Vanessa Brito
[1]
;
Davanzo, Gustavo Gastao
[1]
;
Rocha-Santos, Carla
[1]
;
Ceroni, Alexandre
[1]
;
Michelini, Lisete C.
[1]
Total Authors: 6
|
| Affiliation: | [1] Univ Sao Paulo, Inst Biomed Sci, Dept Physiol & Biophys, Sao Paulo - Brazil
Total Affiliations: 1
|
| Document type: | Journal article |
| Source: | AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY; v. 321, n. 5, p. R732-R741, NOV 2021. |
| Web of Science Citations: | 0 |
| Abstract | |
Although hypertension disrupts the blood-brain barrier (BBB) integrity within the paraventricular nucleus of hypothalamus (PVN) and increases the leakage into the brain parenchyma, exercise training (T) was shown to correct it. Since there is scarce and contradictory information on the mechanism(s) determining hypertension-induced BBB deficit and nothing is known about T induced improvement, we sought to evaluate the paracellular and transcellular transport across the BBB within the PVN in both conditions. Spontaneously hypertensive rats (SHR) and WKY submitted to 4-wk aerobic T or sedentary (S) protocol were chronically catheterized for hemodynamic recordings at rest and intra-arterial administration of dyes (Rhodamine-dextran 70 kDa + FITC-dextran 10 kDa). Brains were harvesting for FITC leakage examination, qPCR evaluation of different BBB constituents and protein expression of caveolin-1 and claudin-5, the main markers of transcytosis and paracellular transport, respectively. Hypertension was characterized by increased arterial pressure and heart rate, augmented sympathetic modulation of heart and vessels, and reduced cardiac parasympathetic control, marked FITC extravasation into the PVN which was accompanied by increased caveolin-1 gene and protein expression, without changes in claudin-5 and others tight junctions' components. SHR-T vs. SHR-S showed a partial pressure reduction, resting bradycardia, improvement of autonomic control of the circulation simultaneously with correction of both FITC leakage and caveolin-1 expression; there was a significant increase in claudin-5 expression. Caveolin-1 content was strongly correlated with improved autonomic control after exercise. Data indicated that within the PVN the transcytosis is the main mechanism governing both hypertension-induced BBB leakage, as well as the exercise-induced correction. (AU) | |
| FAPESP's process: | 18/14544-6 - Blood-brain barrier: a new paradigm in the treatment of hypertension |
| Grantee: | Lisete Compagno Michelini |
| Support Opportunities: | Research Projects - Thematic Grants |