IL6 and atrial fibrillation: In rabbits, the postoperative changes in the percentages of IL-6-positive NP and AF cells were similar to those in rats (Fig. 3f), and the percentages of IL-6-positive NP and AF cells in the gel group were significantly lower than those in the aspiration group at each time point (aspirate vs. gel, NP cells; P = 0.04 on day 1, P < 0.01 on day 4 and 7, P = 0.01 on day 28, AF cells; P < 0.01 at each time point, Fig. 3g,h).