Inhibitory effect of 764-3 on Ca2+ uptake in rat brain synaptosomes.

: In an attempt to examine the effect of 764-3, a purified component extracted from Radix Salviae Miltiorrhizae (RSM), on calcium channel, Ca2+ uptake in rat brain synaptosome stimulated by high-K+ and Glutamate (Glu) was investigated by using radioisotope labeled 45CaCl2. It was found that 764-3 could decrease the uptake of Ca2+ induced by high-K+ (60 mM) and 0.1 mM glutamate in a concentration-dependent manner. The maximum inhibiting rates were 45.22 +/- 4.88% and 37.58 +/- 4.52%, respectively. The results indicated that neuroprotective effect of RSM on cerebral ischemic injury may be related to its blocking effects on calcium channel.