Hrelia S, Biagi P L, Lamers J M, Bordoni A
Department of Biochemistry G. Moruzzi, University of Bologna, Italy.
Cardioscience. 1992 Jun;3(2):91-5.
Using cultures of beating cardiomyocytes from neonatal rats, we have studied the fatty acid composition of phosphatidylinositol, phosphatidylinositol-4-phosphate and phosphatidylinositol-4,5-bisphosphate and the effect of supplementing the culture medium with docosahexaenoic acid on the fatty acid composition of the three phosphoinositides. Docosahexaenoic acid was incorporated into the phosphatidylinositol fraction of the supplemented cells, but not into the phosphatidylinositol-4-phosphate and phosphatidylinositol-4,5-bisphosphate fractions. At complete confluence, the cardiomyocytes were stimulated with an alpha 1-agonist (phenylephrine). This altered the acidic pattern of the phosphoinositides in both control and supplemented cells. The differences observed between the polyphosphorylated classes and the phosphatidylinositol fraction suggest the existence of different mechanisms of selection of fatty acids in the biosynthesis of phosphatidylinositol-4-phosphate and phosphatidylinositol-4,5-bisphosphate.
利用新生大鼠搏动心肌细胞的培养物，我们研究了磷脂酰肌醇、磷脂酰肌醇 - 4 - 磷酸和磷脂酰肌醇 - 4,5 - 二磷酸的脂肪酸组成，以及在培养基中添加二十二碳六烯酸对这三种磷酸肌醇脂肪酸组成的影响。二十二碳六烯酸被掺入到添加细胞的磷脂酰肌醇组分中，但未掺入到磷脂酰肌醇 - 4 - 磷酸和磷脂酰肌醇 - 4,5 - 二磷酸组分中。在完全汇合时，用α1 - 激动剂（去氧肾上腺素）刺激心肌细胞。这改变了对照细胞和添加细胞中磷酸肌醇的酸性模式。多磷酸化类别与磷脂酰肌醇组分之间观察到的差异表明，在磷脂酰肌醇 - 4 - 磷酸和磷脂酰肌醇 - 4,5 - 二磷酸的生物合成中存在不同的脂肪酸选择机制。
