Superior cervical gangliectomy exacerbates the aortic dissection in mice

BACKGROUND: Sympathetic innervation is fundamentally required for physiological aortic homeostasis. Though it plays a vital important role in aortic function, its specific role in aortic dissection (AD) remains unclear. METHODS AND RESULTS: In this study, we explored the role of the sympathetic nervous system in AD by examining the effects of superior cervical ganglionectomy (SCGx) in mice. Using β-aminopropionitrile (BAPN) induced AD mice model at pre-lesional stage, the tyrosine hydroxylase (TH) expression, indicative of sympathetic activity, increased early in AD progression and correlated with aortic elastic lamina degradation. SCGx did not affect aortic structure within 2 weeks without BAPN treatment, but bilateral SCGx exacerbated AD severity, increasing rupture rates and tear range after BAPN and angiotensin II (AngII) treatment. CONCLUSIONS: These findings highlighted the role of sympathetic nervous system in early AD stages and suggested bilateral SCGx may negatively impact AD progression. Furthermore, we found a trend toward smooth muscle cell phenotypic transformation after implementing SCGx in AD, revealing the integrity of the SCG played a pivotal role in preserving aortic homeostasis.