The Role of α7nAChR-Mediated Cholinergic Anti-Inflammatory Pathway in Vagal Nerve Regulated Atrial Fibrillation.

The aim was to investigate the role of the α7nAChR-mediated cholinergic anti-inflammatory pathway in vagal nerve regulated atrial fibrillation (AF).18 beagles (standard dogs for testing) were used in this study, and the effective refractory period (ERP) of atrium and pulmonary veins and AF inducibility were measured hourly during rapid atrial pacing at 800 beats/minute for 6 hours in all beagles. After cessation of 3 hours of RAP, the low-level vagal nerve stimulation (LL-VNS) group (n = 6) was given LL-VNS and injection of salinne (0.5 mL/GP) into four GPs, the methyllycaconitine (MLA, the antagonist of α7nAChR) group (n = 6) was given LL-VNS and injection of MLA into four GPs, and the Control group (n = 6) was given saline into four GPs and the right cervical vagal nerve was exposed without stimulation. Then, the levels of the tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), acetylcholine (ACh), STAT3, and NF-κB proteins were measured. During the first 3 hours of RAP, the ERPs gradually decreased while the dispersion of ERPs (dERPs) and AF inducibility gradually increased in all three groups. During the last 3 hours of 6 hours' RAP in this study, the ERPs in the LL-VNS group were higher, while the dERPs and AF inducibility were significantly lower when compared with the Control and MLA groups at the same time points. The levels of ACh in the serum and atrium in the LL-VNS and MLA groups were higher than in the Control group, and the levels of TNF-α and IL-6 were higher in the Control and MLA groups than in the LL-VNS group. The concentrations of STAT3 in RA and LA tissues were higher in the LL-VNS group while those of NF-κB were lower.In conclusion, the cholinergic anti-inflammatory pathway mediated by α7nACh plays an important role in low-level vagal nerve-regulated AF.

Effect of Shensong Yangxin on the Progression of Paroxysmal Atrial Fibrillation is Correlated with Regulation of Autonomic Nerve Activity.

BACKGROUND: Shensong Yangxin (SSYX), a traditional Chinese herbal medicine, has long been used clinically to treat arrhythmias in China. However, the mechanism of SSYX on atrial fibrillation (AF) is unknown. In this study, we tested the hypothesis that the effect of SSYX on the progression of paroxysmal AF is correlated with the regulation of autonomic nerve activity. METHODS: Eighteen mongrel dogs were randomly divided into control group (n = 6), pacing group (n = 6), and pacing + SSYX group (n = 6). The control group was implanted with pacemakers without pacing; the pacing group was implanted with pacemakers with long-term intermittent atrial pacing; the pacing + SSYX group underwent long-term intermittent atrial pacing and SSYX oral administration. RESULTS: Compared to the pacing group, the parameters of heart rate variability were lower after 8 weeks in the pacing + SSYX group (low-frequency [LF] component: 20.85 ± 3.14 vs. 15.3 ± 1.89 ms 2 , P = 0.004; LF component/high-frequency component: 1.34 ± 0.33 vs. 0.77 ± 0.15, P < 0.001). The atrial effective refractory period (AERP) was shorter and the dispersion of the AERP was higher after 8 weeks in the pacing group, while the changes were suppressed by SSYX intake. The dogs in the pacing group had more episodes and longer durations of AF than that in the pacing + SSYX group. SSYX markedly inhibited the increase in sympathetic nerves and upregulation of tumor necrosis factor-alpha and interleukin-6 expression in the pacing + SSYX group. Furthermore, SSYX suppressed the decrease of acetylcholine and α7 nicotinic acetylcholine receptor protein induced by long-term intermittent atrial pacing. CONCLUSIONS: SSYX substantially prevents atrial electrical remodeling and the progression of AF. These effects of SSYX may have association with regulating the imbalance of autonomic nerve activity and the cholinergic anti-inflammatory pathway.

An annulative transfer hydrogenation strategy enables straightforward access to tetrahydro fused-pyrazine derivatives.

A ruthenium-catalysed annulative transfer hydrogenation strategy, enabling straightforward access to tetrahydro fused-pyrazine derivatives from N-heteroaryl diamines and vicinal diols, has been demonstrated for the first time. Such a synthesis proceeds with unprecedented synthetic effectiveness including high step- and atom efficiency, generation of water as the sole by-product, short reaction time and no need for external high pressure H2 gas, offering an important basis for the transformation of vicinal diols, a class of bio-mass derived resources, into functionalized products.

[Mass Spectrometric Methods for Colorative Mechanism Analysis of Yaozhou Porcelain Glaze].

An in-house-built femtosecond laser ionization time-of-flight mass spectrometry (fs-LI-TOFMS) has been applied to the multi-elemental analysis of porcelain glaze from Yaozhou kiln. The samples are selected representing products of different dynasties, including Tang, Five, Song, Jin, and Ming Dynasty. For exploring the colorative mechanism of Yaozhou porcelain through the elemental analysis of the glaze, the effects of all potential coloring elements, especially transition elements, were considered. There was a speculation that the typical Co-Cr-Fe-Mn recipe was used in the fabrication of Yaozhou black glaze; the low content of Fe and high content of Ni resulted in the porcelain of white glaze; an increase content of P could lead the porcelain to be yellow-glazed. Undoubtedly, this research is an important supplement to the study of the colorative mechanism of the Yaozhou porcelain system.

Atrial autonomic innervation remodelling and atrial fibrillation inducibility after epicardial ganglionic plexi ablation.

AIMS: The effects of ganglionated plexi (GP) ablation on atrial fibrillation (AF) inducibility and atrial autonomic innervation remodelling have not been elucidated. METHODS AND RESULTS: Thirteen dogs were randomly divided into sham-operated group and GP ablation group. All animals underwent a right thoracotomy at the fourth intercostal space. Atrial fibrillation inducibility was assessed by burst rapid pacing at right atrium (RA). After anterior right GP and inferior right GP ablation, AF inducibility was assessed in the GP ablation group. The animals were allowed to recover for 8 weeks, after which, AF was measured again. The levels of atrial natriuretic peptide (ANP) in blood and atrial tissues were examined by radioimmunoassay. Immunocytochemical staining of cardiac nerves was performed in tissues from the dogs. Atrial fibrillation was induced easily in the GP ablation group after 8 weeks although AF was not observed in the sham-operated group, and after instant GP ablation. Compared with that in the sham-operated group, the levels of ANP in the blood and RA increased significantly 8 weeks after GP ablation (111.4 +/- 18.2 vs. 175.1 +/- 25.9; 184.9 +/- 36.3 vs. 299.1 +/- 32.5; P < 0.05). In the GP ablation group, the density of growth-associated protein 43-positive, tyrosine hydroxylase-positive, and choline acetyltransferase-positive nerves in the RA was 821 +/- 752, 481 +/- 627, and 629 +/- 644 per mm(2), respectively, which was significantly (P < 0.01) lower than the nerve density in sham-operated tissues (2590 +/- 841, 1752 +/- 605, and 3147 +/- 886 per mm(2), respectively). CONCLUSION: Atrial autonomic innervations remodelling may be the mechanism of induced AF after GP ablation.