ABSTRACT
Objective: To investigate the effect of bilateral superior cervical ganglionectomy on cardiac remodeling and function in pressure-overloaded heart failure (HF) mice. Methods: Pressure-overloaded HF mouse model was produced by severe thoracic aorta banding (sTAB). Bilateral superior cervical ganglionectomy (SCGx) was performed 2 weeks after sTAB. Twenty four 6-week-old male C57BL/6 mice were randomized divided into 4 groups (n=6 each): control group: sham sTAB+sham SCGx; denervated group: sham sTAB+SCGx; HF group: sTAB+sham SCGx; denervated HF group: sTAB+SCGx. Cardiac function was measured by echocardiography at week 0, 1, 2, and 4 after sTAB, respectively. All mice were sacrificed at the end of week 4 and heart tissues were harvested. HE and Masson staining were performed. Immunohistochemical staining (IHC) for tyrosine hydroxylase (TH), adrenergic receptor β1 (AR-β1) and CD68 was performed. Western blot was used to determine the protein expression level of TH, B type natriuretic peptide (BNP), and AR-β1. Results: Left ventricular ejection fraction (LVEF) declined continuously in HF group. LVEF was similar between denervated HF group and control group at various time points (P>0.05). LVEF was significantly higher in denervated HF group than in HF group at the end of week 4 (P<0.05). HE staining showed that cross sectional cardiomyocyte area was significantly larger in HF group than in control group and denervated HF group (P<0.05), which was similar between denervated HF group and control group (P>0.05). Masson staining showed that fibrosis level was significantly lower in denervated HF group than in HF group (P<0.05). IHC showed that TH+nerves and CD68+ macrophages were significantly increased in HF mice as compared to control mice (P<0.05), whereas this change was abolished in denervated HF group. AR-β1 was significantly down-regulated in HF group compared with control group (P<0.05), which was not affected by denervation (P>0.05). Western blot demonstrated that the expression level of TH and BNP was significantly higher in HF group compared with the control group (P<0.05), whereas this difference was diminished in denervated HF group (P>0.05). Conclusion: Bilateral superior cervical ganglionectomy can reduce sympathetic innervation and macrophage infiltration in pressure overloaded failure heart, thus attenuate cardiac remodeling and improve cardiac function.
Subject(s)
Animals , Male , Mice , Cross-Sectional Studies , Ganglionectomy , Heart Failure , Mice, Inbred C57BL , Stroke Volume , Ventricular Function, Left , Ventricular RemodelingABSTRACT
The human adenosine triphosphate-binding cassette transporter A1(ABCA1)gene is highly polymorphic.Some polymorphisms in promoters (rs2422493 ,rs2740483 ,etc. ) and exons (rs2230806 ,rs4149313 ,etc. )have been reported to be significantly associated with coronary heart disease(CHD ). In terms of the underlying mechanisms ,ABCA1 gene polymorphisms might be associated with CHD through modulating the levels of high-density lipoprotein cholesterol and other lipids ,or through changing ABCA1 protein structure and function. In this article ,the association of ABCA1 gene polymorphisms with CHD and the underlying mechanisms are reviewed.