心房細動中の心拍数は個人差が大きく，その規定因子は房室結節の伝導特性や自律神経系の関与が報告されているが，その他の因子については解明されていない．今回われわれは持続性心房細動のカテーテルアブレーションを行った患者を対象とし，心房細動患者の心拍数に関与する遺伝的要因について検討した．ゲノムワイド関連解析で報告された洞調律中の心拍数との関連を認めた21の遺伝子多型とホルター心電図で得られた24時間総心拍数を調査したところ，ギャップジャンクションの構成蛋白であるコネキシン43をコードするGJA1遺伝子多型（rs1015451）マイナーCアレルが独立した心房細動における心拍数上昇因子であることがわかった．また，GJA1遺伝子多型マイナーCアレルを有する症例は心房内伝導速度が速く，心房細動の周期長が短いこともわかった．GJA1遺伝子多型（rs1015451）は難治性頻脈性心房細動を予測する，新たな遺伝子マーカーとなる可能性がある．

　The postprandial increase in blood triglyceride levels is an independent risk factor for coronary artery disease and a large number of studies has shown that a diet rich in vegetables may provide protection against many chronic diseases. Leaf vegetables generally contain β-carotene, zeaxanthin and chlorophyll including thylakoids. In this study, we investigated the bile acid-binding capacities of thylakoids in vitro and the suppressive effects of it before the administration of a lipid meal on postprandial hypertriglyceridemia in rats using oral fat tolerance/loading tests (OFTT). Consequently, thylakoids bound bile acids in a dose-dependent manner. Following the administration of the lipid meals, increases in the serum triglycerides levels were significantly reduced in rats fed 300 mg/kg bw of thylakoids just before lipid meals. Additionally, the area under the curve showed that a high-dose thylakoids significantly inhibited the absorption of dietary fat. Moreover, the level of fecal bile acid was significantly increased although there were no significant differences in the fecal volume and fecal total lipid levels.

　These results suggest that thylakoid intake before eating a lipid diet induces a suppressive effect of postprandial hypertriglyceridemia to defecate bile acid and confirmed the results of the health-promoting potential dietary thylakoids. This health benefit of thylakoids could be achieved by substantially increasing the consumption of vegetables.