|Budget Amount *help
¥1,900,000 (Direct Cost : ¥1,900,000)
Fiscal Year 1993 : ¥300,000 (Direct Cost : ¥300,000)
Fiscal Year 1992 : ¥800,000 (Direct Cost : ¥800,000)
Fiscal Year 1991 : ¥800,000 (Direct Cost : ¥800,000)
We studied myocardial 1,2-diacylglycerol(DG) content during the development of cardiac hypertrophy since 1,2-DG is thought to play an important role in cells by activating protein kinase C.In spontaneously hypertensive rats, 1,2-DG was elevated by 31%, but the 1,2-DG content became lower to a control level with aging. Enalapril, an angiotenin converting enzyme inhibitor, prevented the elevation of 1,2-DG.Likewise, in cardiomyopathic hamsters and rats with monocrotaline-induced right ventricular hypertrophy, elevated 1,2-DG contents were also observed in the stage of hypertrophy, Whereas this lipid was lowered at the stage of heart failure. On the other hahd, 1,2-DG was decreased in the thyroid-stimulated hypertrophy in rats because thyroid hormones directly promote protein synthesis via nuclear receptors. Pretreatment with a protein synthesis inhibitor decreased 1,2-DG more than thyroid treatment only, implying that elevated RNA inhibited the production of 1,2-DG followed by inactivating protein kinase C.Our results suggest that myocardial 1,2-DG content is associated with hypertrophy.