<原著>Endothelinの心筋肥大作用 : ラット新生児培養心筋細胞を用いた研究

概要

論文の詳細を見る
The induction of hypertrophy by endothelin, a newly discovered novel vasoconstrictor peptide, on cultured neonatal rat cardiac myocytes was investigated. Cultured cardiac myocytes were isolated by mechanical disaggregation and enzymatic digestion with trypsin from neonatal 1 to 3 days old Sprague-Dawley rat ventricles. These cells were cultured in a serum free condition. Endothelin-1,which is the most examined endothelin, was used in this study. Endothelin-1 enlarged the size of cardiac myocytes and induced well developed myofibrils as well as endoplasmic reticulum in the cytoplasm. Cell surface area, protein contents and [^<14>C] phenylalanine (Phe) uptake to the cells increased time-dependently 1,2 and 3 days after the addition of endothelin-1. The [^<14>C] Phe uptake also increased dose-dependently by endothelin-1. The maximum response of endothelin-1 was obtained at around 10^<-8>M, and ED_<50> was about 2×10^<-10>M. These effects were attenuated significantly by nicardipine, a Ca^<2+> channel antagonist, and H-7,a specific protein kinase C inhibitor, but not by HA1004,a weak protein kinase C inhibitor. These results indicate that the mechanism by which endothelin induces hypertrophy of cultured cardiac myocytes is mediated by the increased extracellular Ca^<2+> influx and/or protein kinase C activation.
近畿大学の論文
1991-09-25