Fournier A, Fantini E, Sergiel J P, Athias P, Grynberg A
INRA, Unité de Nutrition Lipidique, Dijon, France.
Cardioscience. 1995 Mar;6(1):71-8.
The cardiovascular beneficial effects of fish oils are currently attributed to docosahexaenoic (C22:6 n-3) and eicosapentaenoic (C20:5 n-3) acids, although most investigations have focused on eicosapentaenoic acid. This study was devoted to the specific effect of docosahexaenoic acid, as compared to eicosapentaenoic acid, on the basal electrophysiological and mechanical characteristics of cultured rat myocardial cells. The myocyte cultures were prepared from newborn rat heart ventricles. The cells were grown for 24 hours in a conventional seric medium, and then incubated in a medium enriched with either docosahexaenoic acid or eicosapentaenoic acid for 96 hours. This treatment resulted in docosahexaenoic acid-rich cells (16% of the phospholipid fatty acids) and docosahexaenoic acid-poor cells (1.5%), both displaying the same phospholipid n-6/n-3 polyunsaturated fatty acid ratio. The transmembrane potentials were recorded with glass microelectrodes. Contractions were monitored photometrically. The action potential amplitude was slightly smaller in docosahexaenoic acid-rich cells (-4 mv), due to a lower plateau phase. There was no difference in action potential duration and spontaneous rate. The contraction measurements were not significantly different between the two groups of cells. We conclude that increasing the docosahexaenoic acid content in cardiomyocyte membrane phospholipids may have modulated the calcium ionic channels governing the plateau phase of the action potential, whereas the other physiological activities remained unaffected.
目前认为鱼油对心血管有益的作用归因于二十二碳六烯酸（C22:6 n-3）和二十碳五烯酸（C20:5 n-3），尽管大多数研究集中在二十碳五烯酸上。本研究旨在探讨与二十碳五烯酸相比，二十二碳六烯酸对培养的大鼠心肌细胞基础电生理和力学特性的具体影响。心肌细胞培养物取自新生大鼠心室。细胞在常规含血清培养基中培养24小时，然后在富含二十二碳六烯酸或二十碳五烯酸的培养基中孵育96小时。这种处理产生了富含二十二碳六烯酸的细胞（磷脂脂肪酸的16%）和缺乏二十二碳六烯酸的细胞（1.5%），两者显示相同的磷脂n-6/n-3多不饱和脂肪酸比例。用玻璃微电极记录跨膜电位。通过光度法监测收缩情况。富含二十二碳六烯酸的细胞中动作电位幅度略小（-4 mV），这是由于平台期较低。动作电位持续时间和自发频率没有差异。两组细胞的收缩测量结果没有显著差异。我们得出结论，增加心肌细胞膜磷脂中二十二碳六烯酸的含量可能调节了控制动作电位平台期的钙离子通道，而其他生理活动未受影响。
