Washed human platelets were loaded with the Ca2+-sensitive photoprotein, aequorin. using hypoosmotic shock treatment-technique. Then aggregation and cytoplasmic ionized calcium concentration ( [Ca2+] i) changes in res...Washed human platelets were loaded with the Ca2+-sensitive photoprotein, aequorin. using hypoosmotic shock treatment-technique. Then aggregation and cytoplasmic ionized calcium concentration ( [Ca2+] i) changes in response to collagen or thrombin were measured simultaneously in the aequorin-loaded human platelets with a Platelet Ionized Calcium Aggregometer. 764-3. an active component isolated from the Chinese medicinal herb Salvia Miltiorrhiza Bge, inhibited platelet [Ca2+]i rise as well as aggregation evoked by collagen or thrombin in the presence of extracellular Ca2+. After the extracellular Ca2+. was removed by addition of EGTA, collagen or thrombin. causing no aggregation. still elicited platelet [Ca2+] i rise which reflected Ca2+ mobilization from intraplatelet stores. Under this condition, 764-3 could also suppress platelet [Ca2+] i rise. Analysis shows that 764-3 inhibrts platelet Ca2+ influx and Ca2+ mobilization with similar potency. which accounts for its suppression of platelet [Ca2+] i rise, and must contribute to its inhibition of platelet aggregation.展开更多
文摘Washed human platelets were loaded with the Ca2+-sensitive photoprotein, aequorin. using hypoosmotic shock treatment-technique. Then aggregation and cytoplasmic ionized calcium concentration ( [Ca2+] i) changes in response to collagen or thrombin were measured simultaneously in the aequorin-loaded human platelets with a Platelet Ionized Calcium Aggregometer. 764-3. an active component isolated from the Chinese medicinal herb Salvia Miltiorrhiza Bge, inhibited platelet [Ca2+]i rise as well as aggregation evoked by collagen or thrombin in the presence of extracellular Ca2+. After the extracellular Ca2+. was removed by addition of EGTA, collagen or thrombin. causing no aggregation. still elicited platelet [Ca2+] i rise which reflected Ca2+ mobilization from intraplatelet stores. Under this condition, 764-3 could also suppress platelet [Ca2+] i rise. Analysis shows that 764-3 inhibrts platelet Ca2+ influx and Ca2+ mobilization with similar potency. which accounts for its suppression of platelet [Ca2+] i rise, and must contribute to its inhibition of platelet aggregation.
基金supported by the grants for scientific researches provided by Ministry of Health of the People s Republic of China and Fujian Province for health and education(WKJ2008-2-59)~~
