|Budget Amount *help
¥6,800,000 (Direct Cost : ¥6,800,000)
Fiscal Year 1991 : ¥1,100,000 (Direct Cost : ¥1,100,000)
Fiscal Year 1990 : ¥5,700,000 (Direct Cost : ¥5,700,000)
It is known that inositol (1,4,5)-trisphosphate (IP_3) stimulates Ca^<2+> release from sarcoplasmic reticulum (SR) in several tissues, but in cardiac myocytes the effect of IP_3 on Ca^<2+> release from sarcoplasmic reticulum is controversial. In this experitment, we have proved that (1,4,5)-IP_3 stimulates Ca^<2+> release from cardiac myocyte sarcoplasmic reticulum by digital-image method in signle cell. In cardiac myocyte treated with saponin, Ca^<2+> release stimulated by 10 muM (1,4,5)-IP_3 was detected by fura-2. In ^<45>Ca^<2+> prelabeled sarcoplasmic reticulum, the maximal Ca^<2+> release was achieved at 10 muM IP_3 for 1 min incubation. The release of Ca^<2+> was higher is SHR sarcoplasmic reticulum than in that of WKY.But it is not clear whether this phenomenon has a significant role in cardiac hypertrophy.