Author + information
- Yanqiu Lai,
- Lilei Yu,
- Bing Huang,
- Guannan Meng,
- Yuhong Wang and
- Hong Jiang
Leptin, one of the main hormones controlling metabolism, has been associated with cardiac dysfunction. However, it is not clear whether leptin could affect atrial ganglionated plexi neural activity and atrial fibrillation inducibility.
Eighteen anesthetized dogs were randomly divided into two groups: leptin group (n=9, leptin microinjection into anterior right ganglionated plexi (ARGP)) and control group (n=9, equivalent saline microinjection into ARGP). The effective refractory period (ERP) at atrial and pulmonary vein sites, window of vulnerability (WOV), ARGP function and neural activities were determined at baseline and 30 minutes after leptin or saline microinjection. At the end of the experiment, the ARGP tissue were taken for the detection of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and c-fos expression.
At baseline, no significant differences in atrial electrophysiological characters were observed between the two groups. However, 30 minutes after leptin microinjection, the ERP at each recording site was significantly decreased and the ∑WOV was greatly increased (37.3 ± 4.3 ms vs. 1.6±1.5 ms, p<0.05) compared to the control group. In addition, the ARGP function and neural activities were significantly enhanced and the expression of IL-6, TNF-α, c-fos were increased in the leptin group rather than the control group.
Leptin could increase the inducibility of AF by enhancing ARGP function and neural activities. Inflammatory activation in ARGP may contribute to these results.